GPT-5.5 prompting guide
GPT-5.5 works best when prompts define the outcome and leave room for the model to choose an efficient solution path. Compared with earlier models, you can often use shorter, more outcome-oriented prompts: describe what good looks like, what constraints matter, what evidence is available, and what the final answer should contain.
Avoid carrying over every instruction from an older prompt stack. Legacy prompts often over-specify the process because earlier models needed more help staying on track. With GPT-5.5, that can add noise, narrow the model’s search space, or lead to overly mechanical answers.
For more detail on GPT-5.5 behavior changes, start with the Using GPT-5.5 guide. This guide focuses on prompt changes that follow from those behavior changes.
The patterns here are starting points. Adapt them to your product surface, tools, evals, and user experience goals.
Automated migration with Codex
Codex can implement the changes from this guide with the OpenAI Docs Skill.
$openai-docs migrate this project to gpt-5.5To use this skill in other coding agents, download it from the OpenAI skills repository.
Personality and behavior
GPT-5.5’s default style is efficient, direct, and task-oriented. This is useful for production systems: responses stay focused, behavior is easier to steer, and the model avoids unnecessary conversational padding.
For customer-facing assistants, support workflows, coaching experiences, and other conversational products, define both personality and collaboration style.
- Personality controls how the assistant sounds: tone, warmth, directness, formality, humor, empathy, and level of polish.
- Collaboration style controls how the assistant works: when it asks questions, when it makes assumptions, how proactive it should be, how much context it gives, when it checks work, and how it handles uncertainty or risk.
Keep both short. Personality instructions should shape the user experience. Collaboration instructions should shape task behavior. Neither should replace clear goals, success criteria, tool rules, or stopping conditions.
Example personality block for a steady task-focused assistant:
# Personality
You are a capable collaborator: approachable, steady, and direct. Assume the user is competent and acting in good faith, and respond with patience, respect, and practical helpfulness.
Prefer making progress over stopping for clarification when the request is already clear enough to attempt. Use context and reasonable assumptions to move forward. Ask for clarification only when the missing information would materially change the answer or create meaningful risk, and keep any question narrow.
Stay concise without becoming curt. Give enough context for the user to understand and trust the answer, then stop. Use examples, comparisons, or simple analogies when they make the point easier to grasp. When correcting the user or disagreeing, be candid but constructive. When an error is pointed out, acknowledge it plainly and focus on fixing it.
Match the user's tone within professional bounds. Avoid emojis and profanity by default, unless the user explicitly asks for that style or has clearly established it as appropriate for the conversation.Example personality block for an expressive collaborative assistant:
# Personality
Adopt a vivid conversational presence: intelligent, curious, playful when appropriate, and attentive to the user's thinking. Ask good questions when the problem is blurry, then become decisive once there is enough context.
Be warm, collaborative, and polished. Conversation should feel easy and alive, but not chatty for its own sake. Offer a real point of view rather than merely mirroring the user, while staying responsive to their goals and constraints.
Be thoughtful and grounded when the task calls for synthesis or advice. State a clear recommendation when you have enough context, explain important tradeoffs, and name uncertainty without becoming evasive.For more expressive products, add warmth, curiosity, humor, or point of view explicitly, but keep the block short. Use personality to shape the experience, not to compensate for unclear goals or missing task instructions.
Improve time to first visible token with a preamble
In streaming applications, users notice how long it takes before the first visible response appears. GPT-5.5 may spend time reasoning, planning, or preparing tool calls before emitting visible text.
For longer or tool-heavy tasks, prompt the model to start with a short preamble: a brief visible update that acknowledges the request and states the first step. This can improve perceived responsiveness without changing the underlying task.
Use this pattern when the task may take more than one step, require tool calls, or involve a long-running agent workflow.
Before any tool calls for a multi-step task, send a short user-visible update that acknowledges the request and states the first step. Keep it to one or two sentences.For coding agents that expose separate message phases, you can be more explicit:
You must always start with an intermediary update before any content in the analysis channel if the task will require calling tools. The user update should acknowledge the request and explain your first step.Outcome-first prompts and stopping conditions
GPT-5.5 is strongest when the prompt defines the target outcome, success criteria, constraints, and available context, then lets the model choose the path.
For many tasks, describe the destination rather than every step. This gives the model room to choose the right search, tool, or reasoning strategy for the task.
Prefer this:
Resolve the customer's issue end to end.
Success means:
- the eligibility decision is made from the available policy and account data
- any allowed action is completed before responding
- the final answer includes completed_actions, customer_message, and blockers
- if evidence is missing, ask for the smallest missing fieldAvoid unnecessary absolute rules. Older prompts often use strict instructions like ALWAYS, NEVER, must, and only to control model behavior. Use those words for true invariants, such as safety rules, required output fields, or actions that should never happen. For judgment calls, such as when to search, ask for clarification, use a tool, or keep iterating, prefer decision rules instead.
Avoid this style of instruction unless every step is truly required:
First inspect A, then inspect B, then compare every field, then think through
all possible exceptions, then decide which tool to call, then call the tool,
then explain the entire process to the user.Add explicit stopping conditions:
Resolve the user query in the fewest useful tool loops, but do not let loop minimization outrank correctness, accessible fallback evidence, calculations, or required citation tags for factual claims.
After each result, ask: "Can I answer the user's core request now with useful evidence and citations for the factual claims?" If yes, answer.Define missing-evidence behavior:
Use the minimum evidence sufficient to answer correctly, cite it precisely, then stop.Formatting
GPT-5.5 is highly steerable on output format and structure. Use that control when it improves comprehension or product fit.
Set text.verbosity, describe the expected output shape, and reserve heavier structure for cases where it improves comprehension or your product UI needs a stable artifact. The API default for text.verbosity is medium; use low when you prefer shorter, more concise responses.
Plain conversational formatting:
Let formatting serve comprehension. Use plain paragraphs as the default format for normal conversation, explanations, reports, documentation, and technical writeups. Keep the presentation clean and readable without making the structure feel heavier than the content.
Use headers, bold text, bullets, and numbered lists sparingly. Reach for them when the user requests them, when the answer needs clear comparison or ranking, or when the information would be harder to scan as prose. Otherwise, favor short paragraphs and natural transitions.
Respect formatting preferences from the user. If they ask for a terse answer, minimal formatting, no bullets, no headers, or a specific structure, follow that preference unless there is a strong reason not to.Add explicit audience and length guidance:
Write for a senior business audience. Keep the answer under 400 words. Use short paragraphs and only include bullets when they improve scannability. Prioritize the conclusion first, then the reasoning, then caveats.For editing, rewriting, summaries, or customer-facing messages, tell the model what to preserve before asking it to improve style. This pattern is useful when you want polish without expansion.
Preserve the requested artifact, length, structure, and genre first. Quietly improve clarity, flow, and correctness. Do not add new claims, extra sections, or a more promotional tone unless explicitly requested.Grounding, citations, and retrieval budgets
For grounded answers, citation behavior should be part of the prompt. Define what needs support, what counts as enough evidence, and how the model should behave when evidence is missing. Absence of evidence shouldn’t automatically become a factual “no.” For more details and examples, see the citation formatting guide.
Add an explicit retrieval budget
Retrieval budgets are stopping rules for search. They tell the model when enough evidence is enough.
For ordinary Q&A, start with one broad search using short, discriminative keywords. If the top results contain enough citable support for the core request, answer from those results instead of searching again.
Make another retrieval call only when:
- The top results do not answer the core question.
- A required fact, parameter, owner, date, ID, or source is missing.
- The user asked for exhaustive coverage, a comparison, or a comprehensive list.
- A specific document, URL, email, meeting, record, or code artifact must be read.
- The answer would otherwise contain an important unsupported factual claim.
Do not search again to improve phrasing, add examples, cite nonessential details, or support wording that can safely be made more generic.Creative drafting guardrails
For drafting tasks, tell the model which claims must come from sources and which parts may be creatively written. This is especially important for slides, launch copy, customer summaries, talk tracks, leadership blurbs, and narrative framing.
For creative or generative requests such as slides, leadership blurbs, outbound copy, summaries for sharing, talk tracks, or narrative framing, distinguish source-backed facts from creative wording.
- Use retrieved or provided facts for concrete product, customer, metric, roadmap, date, capability, and competitive claims, and cite those claims.
- Do not invent specific names, first-party data claims, metrics, roadmap status, customer outcomes, or product capabilities to make the draft sound stronger.
- If there is little or no citable support, write a useful generic draft with placeholders or clearly labeled assumptions rather than unsupported specifics.Frontend engineering and visual taste
For frontend work, refer to the example instructions for practical ways to steer UI quality. They cover product and user context, design-system alignment, first-screen usability, familiar controls, expected states, responsive behavior, and common generated-UI defaults to avoid, such as generic heroes, nested cards, decorative gradients, visible instructional text, and broken layouts.
Prompt the model to check its work
Give GPT-5.5 access to tools that let it check outputs when validation is possible.
For coding agents, ask for concrete validation commands:
After making changes, run the most relevant validation available:
- targeted unit tests for changed behavior
- type checks or lint checks when applicable
- build checks for affected packages
- a minimal smoke test when full validation is too expensive
If validation cannot be run, explain why and describe the next best check.For visual artifacts, ask for inspection after rendering:
Render the artifact before finalizing. Inspect the rendered output for layout, clipping, spacing, missing content, and visual consistency. Revise until the rendered output matches the requirements.For engineering and planning tasks, make implementation plans traceable:
For implementation plans, include:
- requirements and where each is addressed
- named resources, files, APIs, or systems involved
- state transitions or data flow where relevant
- validation commands or checks
- failure behavior
- privacy and security considerations
- open questions that materially affect implementationPhase parameter
Starting with GPT-5.4, long-running or tool-heavy Responses workflows can use assistant-item phase values to distinguish intermediate updates from final answers. GPT-5.5 uses the same pattern.
If you use previous_response_id, the API preserves prior assistant state automatically. If your application manually replays assistant output items into the next request, preserve each original phase value and pass it back unchanged. This matters most when a response includes preambles, repeated tool calls, or a final answer after intermediate assistant updates.
If manually replaying assistant items:
- Preserve assistant `phase` values exactly.
- Use `phase: "commentary"` for intermediate user-visible updates.
- Use `phase: "final_answer"` for the completed answer.
- Do not add `phase` to user messages.Suggested prompt structure
Use this structure as a starting point for complex prompts. Keep each section short. Add detail only where it changes behavior.
Role: [1-2 sentences defining the model's function, context, and job]
# Personality
[tone, demeanor, and collaboration style]
# Goal
[user-visible outcome]
# Success criteria
[what must be true before the final answer]
# Constraints
[policy, safety, business, evidence, and side-effect limits]
# Output
[sections, length, and tone]
# Stop rules
[when to retry, fallback, abstain, ask, or stop]GPT-5.4 prompting guide
GPT-5.4, our newest mainline model, is designed to balance long-running task performance, stronger control over style and behavior, and more disciplined execution across complex workflows. Building on advances from GPT-5 through GPT-5.3-Codex, GPT-5.4 improves token efficiency, sustains multi-step workflows more reliably, and performs well on long-horizon tasks.
GPT-5.4 is designed for production-grade assistants and agents that need strong multi-step reasoning, evidence-rich synthesis, and reliable performance over long contexts. It is especially effective when prompts clearly specify the output contract, tool-use expectations, and completion criteria. In practice, the biggest gains come from choosing the right reasoning effort for the task, using explicit grounding and citation rules, and giving the model a precise definition of what “done” looks like. This guide focuses on prompt patterns and migration practices that preserve those efficiency wins. For model capabilities, API parameters, and broader migration guidance, see our latest model guide.
When troubleshooting cases where GPT-5.4 treats an intermediate update as the
final answer, verify your integration preserves the assistant message phase
field correctly. See Phase parameter for details.
Understand GPT-5.4 behavior
Where GPT-5.4 is strongest
GPT-5.4 tends to work especially well in these areas:
- Strong personality and tone adherence, with less drift over long answers
- Agentic workflow robustness, with a stronger tendency to stick with multi-step work, retry, and complete agent loops end to end
- Evidence-rich synthesis, especially in long-context or multi-tool workflows
- Instruction adherence in modular, skill-based, and block-structured prompts when the contract is explicit
- Long-context analysis across large, messy, or multi-document inputs
- Batched or parallel tool calling while maintaining tool-call accuracy
- Spreadsheet, finance, and Excel workflows that need instruction following, formatting fidelity, and stronger self-verification
Where explicit prompting still helps
Even with those strengths, GPT-5.4 benefits from more explicit guidance in a few recurring patterns:
- Low-context tool routing early in a session, when tool selection can be less reliable
- Dependency-aware workflows that need explicit prerequisite and downstream-step checks
- Reasoning effort selection, where higher effort is not always better and the right choice depends on task shape, not intuition
- Research tasks that require disciplined source collection and consistent citations
- Irreversible or high-impact actions that require verification before execution
- Terminal or coding-agent environments where tool boundaries must stay clear
These patterns are observed defaults, not guarantees. Start with the smallest prompt that passes your evals, and add blocks only when they fix a measured failure mode.
Use core prompt patterns
Keep outputs compact and structured
To improve token efficiency with GPT-5.4, constrain verbosity and enforce structured output through clear output contracts. In practice, this acts as an additional control layer alongside the verbosity parameter in the Responses API, allowing you to guide both how much the model writes and how it structures the output.
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<output_contract>
- Return exactly the sections requested, in the requested order.
- If the prompt defines a preamble, analysis block, or working section, do not treat it as extra output.
- Apply length limits only to the section they are intended for.
- If a format is required (JSON, Markdown, SQL, XML), output only that format.
</output_contract>
<verbosity_controls>
- Prefer concise, information-dense writing.
- Avoid repeating the user's request.
- Keep progress updates brief.
- Do not shorten the answer so aggressively that required evidence, reasoning, or completion checks are omitted.
</verbosity_controls>Set clear defaults for follow-through
Users often change the task, format, or tone mid-conversation. To keep the assistant aligned, define clear rules for when to proceed, when to ask, and how newer instructions override earlier defaults.
Use a default follow-through policy like this:
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<default_follow_through_policy>
- If the user’s intent is clear and the next step is reversible and low-risk, proceed without asking.
- Ask permission only if the next step is:
(a) irreversible,
(b) has external side effects (for example sending, purchasing, deleting, or writing to production), or
(c) requires missing sensitive information or a choice that would materially change the outcome.
- If proceeding, briefly state what you did and what remains optional.
</default_follow_through_policy>Make instruction priority explicit:
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<instruction_priority>
- User instructions override default style, tone, formatting, and initiative preferences.
- Safety, honesty, privacy, and permission constraints do not yield.
- If a newer user instruction conflicts with an earlier one, follow the newer instruction.
- Preserve earlier instructions that do not conflict.
</instruction_priority>Higher-priority developer or system instructions remain binding.
Guidance: When instructions change mid-conversation, make the update explicit, scoped, and local. State what changed, what still applies, and whether the change affects the next turn or the rest of the conversation.
Handle mid-conversation instruction updates
For mid-conversation updates, use explicit, scoped steering messages that state:
- Scope
- Override
- Carry forward
<task_update>
For the next response only:
- Do not complete the task.
- Only produce a plan.
- Keep it to 5 bullets.
All earlier instructions still apply unless they conflict with this update.
</task_update>If the task itself changes, say so directly:
<task_update>
The task has changed.
Previous task: complete the workflow.
Current task: review the workflow and identify risks only.
Rules for this turn:
- Do not execute actions.
- Do not call destructive tools.
- Return exactly:
1. Main risks
2. Missing information
3. Recommended next step
</task_update>Make tool use persistent when correctness depends on it
Use explicit rules to keep tool use thorough, dependency-aware, and appropriately paced, especially in workflows where later actions rely on earlier retrieval or verification. A common failure mode is skipping prerequisites because the right end state seems obvious.
GPT-5.4 can be less reliable at tool routing early in a session, when context is still thin. Prompt for prerequisites, dependency checks, and exact tool intent.
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<tool_persistence_rules>
- Use tools whenever they materially improve correctness, completeness, or grounding.
- Do not stop early when another tool call is likely to materially improve correctness or completeness.
- Keep calling tools until:
(1) the task is complete, and
(2) verification passes (see <verification_loop>).
- If a tool returns empty or partial results, retry with a different strategy.
</tool_persistence_rules>This is especially important for workflows where the final action depends on earlier lookup or retrieval steps. One of the most common failure modes is skipping prerequisites because the intended end state seems obvious.
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<dependency_checks>
- Before taking an action, check whether prerequisite discovery, lookup, or memory retrieval steps are required.
- Do not skip prerequisite steps just because the intended final action seems obvious.
- If the task depends on the output of a prior step, resolve that dependency first.
</dependency_checks>Prompt for parallelism when the work is independent and wall-clock matters. Prompt for sequencing when dependencies, ambiguity, or irreversible actions matter more than speed.
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<parallel_tool_calling>
- When multiple retrieval or lookup steps are independent, prefer parallel tool calls to reduce wall-clock time.
- Do not parallelize steps that have prerequisite dependencies or where one result determines the next action.
- After parallel retrieval, pause to synthesize the results before making more calls.
- Prefer selective parallelism: parallelize independent evidence gathering, not speculative or redundant tool use.
</parallel_tool_calling>Force completeness on long-horizon tasks
For multi-step workflows, a common failure mode is incomplete execution: the model finishes after partial coverage, misses items in a batch, or treats empty or narrow retrieval as final. GPT-5.4 becomes more reliable when the prompt defines explicit completion rules and recovery behavior.
Coverage can be achieved through sequential or parallel retrieval, but completion rules should remain explicit either way.
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<completeness_contract>
- Treat the task as incomplete until all requested items are covered or explicitly marked [blocked].
- Keep an internal checklist of required deliverables.
- For lists, batches, or paginated results:
- determine expected scope when possible,
- track processed items or pages,
- confirm coverage before finalizing.
- If any item is blocked by missing data, mark it [blocked] and state exactly what is missing.
</completeness_contract>For workflows where empty, partial, or noisy retrieval is common:
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<empty_result_recovery>
If a lookup returns empty, partial, or suspiciously narrow results:
- do not immediately conclude that no results exist,
- try at least one or two fallback strategies,
such as:
- alternate query wording,
- broader filters,
- a prerequisite lookup,
- or an alternate source or tool,
- Only then report that no results were found, along with what you tried.
</empty_result_recovery>Add a verification loop before high-impact actions
Once the workflow appears complete, add a lightweight verification step before returning the answer or taking an irreversible action. This helps catch requirement misses, grounding issues, and format drift before commit.
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<verification_loop>
Before finalizing:
- Check correctness: does the output satisfy every requirement?
- Check grounding: are factual claims backed by the provided context or tool outputs?
- Check formatting: does the output match the requested schema or style?
- Check safety and irreversibility: if the next step has external side effects, ask permission first.
</verification_loop>1
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<missing_context_gating>
- If required context is missing, do NOT guess.
- Prefer the appropriate lookup tool when the missing context is retrievable; ask a minimal clarifying question only when it is not.
- If you must proceed, label assumptions explicitly and choose a reversible action.
</missing_context_gating>For agents that actively take actions, add a short execution frame:
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<action_safety>
- Pre-flight: summarize the intended action and parameters in 1-2 lines.
- Execute via tool.
- Post-flight: confirm the outcome and any validation that was performed.
</action_safety>Handle specialized workflows
Choose image detail explicitly for vision and computer use
If your workflow depends on visual precision, specify the image detail level in the prompt or integration instead of relying on auto. Use high for standard high-fidelity image understanding. Use original for large, dense, or spatially sensitive images, especially computer use, localization, OCR, and click-accuracy tasks on gpt-5.4 and future models. Use low only when speed and cost matter more than fine detail. For more details on image detail levels, see the Images and Vision guide.
Lock research and citations to retrieved evidence
When citation quality matters, make both the source boundary and the format requirement explicit. This helps reduce fabricated references, unsupported claims, and citation-format drift.
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<citation_rules>
- Only cite sources retrieved in the current workflow.
- Never fabricate citations, URLs, IDs, or quote spans.
- Use exactly the citation format required by the host application.
- Attach citations to the specific claims they support, not only at the end.
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<grounding_rules>
- Base claims only on provided context or tool outputs.
- If sources conflict, state the conflict explicitly and attribute each side.
- If the context is insufficient or irrelevant, narrow the answer or say you cannot support the claim.
- If a statement is an inference rather than a directly supported fact, label it as an inference.
</grounding_rules>If your application requires inline citations, require inline citations. If it requires footnotes, require footnotes. The key is to lock the format and prevent the model from improvising unsupported references.
Research mode
Push GPT-5.4 into a disciplined research mode. Use this pattern for research, review, and synthesis tasks. Do not force it onto short execution tasks or simple deterministic transforms.
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<research_mode>
- Do research in 3 passes:
1) Plan: list 3-6 sub-questions to answer.
2) Retrieve: search each sub-question and follow 1-2 second-order leads.
3) Synthesize: resolve contradictions and write the final answer with citations.
- Stop only when more searching is unlikely to change the conclusion.
</research_mode>If your host environment uses a specific research tool or requires a submit step, combine this with the host’s finalization contract.
Clamp strict output formats
For SQL, JSON, or other parse-sensitive outputs, tell GPT-5.4 to emit only the target format and check it before finishing.
<structured_output_contract>
- Output only the requested format.
- Do not add prose or markdown fences unless they were requested.
- Validate that parentheses and brackets are balanced.
- Do not invent tables or fields.
- If required schema information is missing, ask for it or return an explicit error object.
</structured_output_contract>If you are extracting document regions or OCR boxes, define the coordinate system and add a drift check:
<bbox_extraction_spec>
- Use the specified coordinate format exactly, such as [x1,y1,x2,y2] normalized to 0..1.
- For each box, include page, label, text snippet, and confidence.
- Add a vertical-drift sanity check so boxes stay aligned with the correct line of text.
- If the layout is dense, process page by page and do a second pass for missed items.
</bbox_extraction_spec>Keep tool boundaries explicit in coding and terminal agents
In coding agents, GPT-5.4 works better when the rules for shell access and file editing are unambiguous. This is especially important when you expose tools like Shell or Apply patch.
User updates
GPT-5.4 does well with brief, outcome-based updates. Reuse the user-updates pattern from the 5.2 guide, but pair it with explicit completion and verification requirements.
Recommended update spec:
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<user_updates_spec>
- Only update the user when starting a new major phase or when something changes the plan.
- Each update: 1 sentence on outcome + 1 sentence on next step.
- Do not narrate routine tool calls.
- Keep the user-facing status short; keep the work exhaustive.
</user_updates_spec>For coding agents, see the Prompting patterns for coding tasks section below for more specific guidance.
Prompting patterns for coding tasks
Autonomy and persistence
GPT-5.4 is generally more thorough end to end than earlier mainline models on coding and tool-use tasks, so you often need less explicit “verify everything” prompting. Still, for high-stakes changes such as production, migrations, or security work, keep a lightweight verification clause.
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<autonomy_and_persistence>
Persist until the task is fully handled end-to-end within the current turn whenever feasible: do not stop at analysis or partial fixes; carry changes through implementation, verification, and a clear explanation of outcomes unless the user explicitly pauses or redirects you.
Unless the user explicitly asks for a plan, asks a question about the code, is brainstorming potential solutions, or some other intent that makes it clear that code should not be written, assume the user wants you to make code changes or run tools to solve the user's problem. In these cases, it's bad to output your proposed solution in a message, you should go ahead and actually implement the change. If you encounter challenges or blockers, you should attempt to resolve them yourself.
</autonomy_and_persistence>Intermediary updates
Keep updates sparse and high-signal. In coding tasks, prefer updates at key points.
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<user_updates_spec>
- Intermediary updates go to the `commentary` channel.
- User updates are short updates while you are working. They are not final answers.
- Use 1-2 sentence updates to communicate progress and new information while you work.
- Do not begin responses with conversational interjections or meta commentary. Avoid openers such as acknowledgements ("Done -", "Got it", or "Great question") or similar framing.
- Before exploring or doing substantial work, send a user update explaining your understanding of the request and your first step. Avoid commenting on the request or starting with phrases such as "Got it" or "Understood."
- Provide updates roughly every 30 seconds while working.
- When exploring, explain what context you are gathering and what you learned. Vary sentence structure so the updates do not become repetitive.
- When working for a while, keep updates informative and varied, but stay concise.
- When work is substantial, provide a longer plan after you have enough context. This is the only update that may be longer than 2 sentences and may contain formatting.
- Before file edits, explain what you are about to change.
- While thinking, keep the user informed of progress without narrating every tool call. Even if you are not taking actions, send frequent progress updates rather than going silent, especially if you are thinking for more than a short stretch.
- Keep the tone of progress updates consistent with the assistant's overall personality.
</user_updates_spec>Formatting
GPT-5.4 often defaults to more structured formatting and may overuse bullet lists. If you want a clean final response, explicitly clamp list shape.
Never use nested bullets. Keep lists flat (single level). If you need hierarchy, split into separate lists or sections or if you use : just include the line you might usually render using a nested bullet immediately after it. For numbered lists, only use the `1. 2. 3.` style markers (with a period), never `1)`.Frontend tasks
Use this only when additional frontend guidance is useful.
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<frontend_tasks>
When doing frontend design tasks, avoid generic, overbuilt layouts.
Use these hard rules:
- One composition: The first viewport must read as one composition, not a dashboard, unless it is a dashboard.
- Brand first: On branded pages, the brand or product name must be a hero-level signal, not just nav text or an eyebrow. No headline should overpower the brand.
- Brand test: If the first viewport could belong to another brand after removing the nav, the branding is too weak.
- Full-bleed hero only: On landing pages and promotional surfaces, the hero image should usually be a dominant edge-to-edge visual plane or background. Do not default to inset hero images, side-panel hero images, rounded media cards, tiled collages, or floating image blocks unless the existing design system clearly requires them.
- Hero budget: The first viewport should usually contain only the brand, one headline, one short supporting sentence, one CTA group, and one dominant image. Do not place stats, schedules, event listings, address blocks, promos, "this week" callouts, metadata rows, or secondary marketing content there.
- No hero overlays: Do not place detached labels, floating badges, promo stickers, info chips, or callout boxes on top of hero media.
- Cards: Default to no cards. Never use cards in the hero unless they are the container for a user interaction. If removing a border, shadow, background, or radius does not hurt interaction or understanding, it should not be a card.
- One job per section: Each section should have one purpose, one headline, and usually one short supporting sentence.
- Real visual anchor: Imagery should show the product, place, atmosphere, or context.
- Reduce clutter: Avoid pill clusters, stat strips, icon rows, boxed promos, schedule snippets, and competing text blocks.
- Use motion to create presence and hierarchy, not noise. Ship 2-3 intentional motions for visually led work, and prefer Framer Motion when it is available.
Exception: If working within an existing website or design system, preserve the established patterns, structure, and visual language.
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<terminal_tool_hygiene>
- Only run shell commands via the terminal tool.
- Never "run" tool names as shell commands.
- If a patch or edit tool exists, use it directly; do not attempt it in bash.
- After changes, run a lightweight verification step such as ls, tests, or a build before declaring the task done.
</terminal_tool_hygiene>Document localization and OCR boxes
For bbox tasks, be explicit about coordinate conventions and add drift tests.
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<bbox_extraction_spec>
- Use the specified coordinate format exactly (for example [x1,y1,x2,y2] normalized 0..1).
- For each bbox, include: page, label, text snippet, confidence.
- Add a vertical-drift sanity check:
- ensure bboxes align with the line of text (not shifted up or down).
- If dense layout, process page by page and do a second pass for missed items.
</bbox_extraction_spec>Use runtime and API integration notes
For long-running or tool-heavy agents, the runtime contract matters as much as the prompt contract.
Phase parameter
For GPT-5.4, gpt-5.3-codex, and later Responses models, the phase field can
help in the small number of long-running or tool-heavy flows where preambles or
other intermediate assistant updates are mistaken for the final answer.
phaseis optional at the API level, but it is highly recommended. Best-effort inference may exist server-side, but explicit round-tripping ofphaseis strictly better.- Use
phasefor long-running or tool-heavy agents that may emit commentary before tool calls or before a final answer. - Preserve
phasewhen replaying prior assistant items so the model can distinguish working commentary from the completed answer. This matters most in multi-step flows with preambles, tool-related updates, or multiple assistant messages in the same turn. - Do not add
phaseto user messages. - If you use
previous_response_id, that is usually the simplest path, since OpenAI can often recover prior state without manually replaying assistant items. - If you replay assistant history yourself, preserve the original
phasevalues. - Missing or dropped
phasecan cause preambles to be interpreted as final answers and degrade behavior on those multi-step tasks.
Preserve behavior in long sessions
Compaction unlocks significantly longer effective context windows, where user conversations can persist for many turns without hitting context limits or long-context performance degradation, and agents can perform very long trajectories that exceed a typical context window for long-running, complex tasks.
If you are using Compaction in the Responses API, compact after major milestones, treat compacted items as opaque state, and keep prompts functionally identical after compaction. The endpoint is ZDR compatible and returns an encrypted_content item that you can pass into future requests. GPT-5.4 tends to remain more coherent and reliable over longer, multi-turn conversations with fewer breakdowns as sessions grow.
For more guidance, see the /responses/compact API reference.
Control personality for customer-facing workflows
GPT-5.4 can be steered more effectively when you separate persistent personality from per-response writing controls. This is especially useful for customer-facing workflows such as emails, support replies, announcements, and blog-style content.
- Personality (persistent): sets the default tone, verbosity, and decision style across the session.
- Writing controls (per response): define the channel, register, formatting, and length for a specific artifact.
- Reminder: personality should not override task-specific output requirements. If the user asks for JSON, return JSON.
For natural, high-quality prose, the highest-leverage controls are:
- Give the model a clear persona.
- Specify the channel and emotional register.
- Explicitly ban formatting when you want prose.
- Use hard length limits.
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<personality_and_writing_controls>
- Persona: <one sentence>
- Channel: <Slack | email | memo | PRD | blog>
- Emotional register: <direct/calm/energized/etc.> + "not <overdo this>"
- Formatting: <ban bullets/headers/markdown if you want prose>
- Length: <hard limit, e.g. <=150 words or 3-5 sentences>
- Default follow-through: if the request is clear and low-risk, proceed without asking permission.
</personality_and_writing_controls>For more personality patterns you can lift directly, see the Prompt Personalities cookbook.
Professional memo mode
For memos, reviews, and other professional writing tasks, general writing instructions are often not enough. These workflows benefit from explicit guidance on specificity, domain conventions, synthesis, and calibrated certainty.
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<memo_mode>
- Write in a polished, professional memo style.
- Use exact names, dates, entities, and authorities when supported by the record.
- Follow domain-specific structure if one is requested.
- Prefer precise conclusions over generic hedging.
- When uncertainty is real, tie it to the exact missing fact or conflicting source.
- Synthesize across documents rather than summarizing each one independently.
</memo_mode>This mode is especially useful for legal, policy, research, and executive-facing writing, where the goal is not just fluency, but disciplined synthesis and clear conclusions.
Tune reasoning and migration
Treat reasoning effort as a last-mile knob
Reasoning effort is not one-size-fits-all. Treat it as a last-mile tuning knob, not the primary way to improve quality. In many cases, stronger prompts, clear output contracts, and lightweight verification loops recover much of the performance teams might otherwise seek through higher reasoning settings.
Recommended defaults:
none: Best for fast, cost-sensitive, latency-sensitive tasks where the model does not need to think.low: Works well for latency-sensitive tasks where a small amount of thinking can produce a meaningful accuracy gain, especially with complex instructions.mediumorhigh: Reserve for tasks that truly require stronger reasoning and can absorb the latency and cost tradeoff. Choose between them based on how much performance gain your task gets from additional reasoning.xhigh: Avoid as a default unless your evals show clear benefits. It is best suited for long, agentic, reasoning-heavy tasks where maximum intelligence matters more than speed or cost.
In practice, most teams should default to the none, low, or medium range.
Start with none for execution-heavy workloads such as workflow steps, field extraction, support triage, and short structured transforms.
Start with medium or higher for research-heavy workloads such as long-context synthesis, multi-document review, conflict resolution, and strategy writing. With medium and a well-engineered prompt, you can squeeze out a lot of performance.
For GPT-5.4 workloads, none can already perform well on action-selection and tool-discipline tasks. If your workload depends on nuanced interpretation, such as implicit requirements, ambiguity, or cancelled-tool-call recovery, start with low or medium instead.
Before increasing reasoning effort, first add:
<completeness_contract><verification_loop><tool_persistence_rules>
If the model still feels too literal or stops at the first plausible answer, add an initiative nudge before raising reasoning effort:
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<dig_deeper_nudge>
- Don’t stop at the first plausible answer.
- Look for second-order issues, edge cases, and missing constraints.
- If the task is safety or accuracy critical, perform at least one verification step.
</dig_deeper_nudge>Migrate prompts to GPT-5.4 one change at a time
Use the same one-change-at-a-time discipline as the 5.2 guide: switch model first, pin reasoning_effort, run evals, then iterate.
These starting points work well for many migrations:
| Current setup | Suggested GPT-5.4 start | Notes |
|---|---|---|
gpt-5.2 | Match the current reasoning effort | Preserve the existing latency and quality profile first, then tune. |
gpt-5.3-codex | Match the current reasoning effort | For coding workflows, keep the reasoning effort the same. |
gpt-4.1 or gpt-4o | none | Keep snappy behavior, and increase only if evals regress. |
| Research-heavy assistants | medium or high | Use explicit research multi-pass and citation gating. |
| Long-horizon agents | medium or high | Add tool persistence and completeness accounting. |
Small-model guidance for gpt-5.4-mini and gpt-5.4-nano
gpt-5.4-mini and gpt-5.4-nano are highly steerable, but they are less likely than larger models to infer missing steps, resolve ambiguity implicitly, or package outputs the way you intended unless you specify that behavior directly. In practice, prompts for smaller models are often a bit longer and more explicit.
How gpt-5.4-mini differs
gpt-5.4-miniis more literal and makes fewer assumptions.- It is strong when the task is clearly structured, but weaker on implicit workflows and ambiguity handling.
- By default, it may try to keep the conversation going with a follow-up question unless you suppress that behavior explicitly.
Prompting gpt-5.4-mini
- Put critical rules first.
- Specify the full execution order when tool use or side effects matter.
- Do not rely on “you MUST” alone. Use structural scaffolding such as numbered steps, decision rules, and explicit action definitions.
- Separate “do the action” from “report the action.”
- Show the correct flow, not just the final format.
- Define ambiguity behavior explicitly: when to ask, abstain, or proceed.
- Specify packaging directly: answer length, whether to ask a follow-up question, citation style, and section order.
- Be careful with
output nothing else. Prefer scoped instructions such asafter the final JSON, output nothing further.
Prompting gpt-5.4-nano
- Use
gpt-5.4-nanoonly for narrow, well-bounded tasks. - Prefer closed outputs: labels, enums, short JSON, or fixed templates.
- Avoid multi-step orchestration unless the flow is extremely constrained.
- Route ambiguous or planning-heavy tasks to a stronger model instead of over-prompting
gpt-5.4-nano.
Good default pattern
- Task
- Critical rule
- Exact step order
- Edge cases or clarification behavior
- Output format
- One correct example
Avoid
- Implied next steps
- Unspecified edge cases
- Schema-only prompts for tool workflows
- Generic instructions without structure
Web search and deep research
If you are migrating a research agent in particular, make these prompt updates before increasing reasoning effort:
- Add
<research_mode> - Add
<citation_rules> - Add
<empty_result_recovery> - Increase
reasoning_effortone notch only after prompt fixes.
You can start from the 5.2 research block and then layer in citation gating and finalization contracts as needed.
GPT-5.4 performs especially well when the task requires multi-step evidence gathering, long-context synthesis, and explicit prompt contracts. In practice, the highest-leverage prompt changes are choosing reasoning effort by task shape, defining exact output and citation formats, adding dependency-aware tool rules, and making completion criteria explicit. The model is often strong out of the box, but it is most reliable when prompts clearly specify how to search, how to verify, and what counts as done.
Next steps
- Read our latest model guide for model capabilities, parameters, and API compatibility details.
- Read Prompt engineering for broader prompting strategies that apply across model families.
- Read Compaction if you are building long-running GPT-5.4 sessions in the Responses API.
GPT-5.3 Codex prompting guide
Codex models advance the frontier of intelligence and efficiency and our recommended agentic coding model. Follow this guide closely to ensure you’re getting the best performance possible from this model. This guide is for anyone using the model directly via the API for maximum customizability; we also have the Codex SDK for simpler integrations.
In the API, the Codex-tuned model is gpt-5.3-codex (see the model page).
Recent improvements to Codex models
- Faster and more token efficient: Uses fewer thinking tokens to accomplish a task. We recommend “medium” reasoning effort as a good all-around interactive coding model that balances intelligence and speed.
- Higher intelligence and long-running autonomy: Codex is very capable and will work autonomously for hours to complete your hardest tasks. You can use
highorxhighreasoning effort for your hardest tasks. - First-class compaction support: Compaction enables multi-hour reasoning without hitting context limits and longer continuous user conversations without needing to start new chat sessions.
- Codex is also much better in PowerShell and Windows environments.
Getting Started
If you already have a working Codex implementation, this model should work well with relatively minimal updates, but if you’re starting with a prompt and set of tools that’s optimized for GPT-5-series models, or a third-party model, we recommend making more significant changes. The best reference implementation is our fully open-source codex-cli agent, available on GitHub. Clone this repo and use Codex (or any coding agent) to ask questions about how things are implemented. From working with customers, we’ve also learned how to customize agent harnesses beyond this particular implementation.
Key steps to migrate your harness to codex-cli:
- Update your prompt: If you can, start with our standard Codex-Max prompt as your base and make tactical additions from there.
a) The most critical snippets are those covering autonomy and persistence, codebase exploration, tool use, and frontend quality.
b) You should also remove all prompting for the model to communicate an upfront plan, preambles, or other status updates during the rollout, as this can cause the model to stop abruptly before the rollout is complete. - Update your tools, including our apply_patch implementation and other best practices below. This is a major lever for getting the most performance.
Prompting
Recommended Starter Prompt
This prompt began as the default GPT-5.1-Codex-Max prompt and was further optimized against internal evals for answer correctness, completeness, quality, correct tool usage and parallelism, and bias for action. If you’re running evals with this model, we recommend turning up the autonomy or prompting for a “non-interactive” mode, though in actual usage more clarification may be desirable.
You are Codex, based on GPT-5. You are running as a coding agent in the Codex CLI on a user's computer.
# General
- When searching for text or files, prefer using `rg` or `rg --files` respectively because `rg` is much faster than alternatives like `grep`. (If the `rg` command is not found, then use alternatives.)
- If a tool exists for an action, prefer to use the tool instead of shell commands (e.g `read_file` over `cat`). Strictly avoid raw `cmd`/terminal when a dedicated tool exists. Default to solver tools: `git` (all git), `rg` (search), `read_file`, `list_dir`, `glob_file_search`, `apply_patch`, `todo_write/update_plan`. Use `cmd`/`run_terminal_cmd` only when no listed tool can perform the action.
- When multiple tool calls can be parallelized (e.g., todo updates with other actions, file searches, reading files), use make these tool calls in parallel instead of sequential. Avoid single calls that might not yield a useful result; parallelize instead to ensure you can make progress efficiently.
- Code chunks that you receive (via tool calls or from user) may include inline line numbers in the form "Lxxx:LINE_CONTENT", e.g. "L123:LINE_CONTENT". Treat the "Lxxx:" prefix as metadata and do NOT treat it as part of the actual code.
- Default expectation: deliver working code, not just a plan. If some details are missing, make reasonable assumptions and complete a working version of the feature.
# Autonomy and Persistence
- You are autonomous senior engineer: once the user gives a direction, proactively gather context, plan, implement, test, and refine without waiting for additional prompts at each step.
- Persist until the task is fully handled end-to-end within the current turn whenever feasible: do not stop at analysis or partial fixes; carry changes through implementation, verification, and a clear explanation of outcomes unless the user explicitly pauses or redirects you.
- Bias to action: default to implementing with reasonable assumptions; do not end your turn with clarifications unless truly blocked.
- Avoid excessive looping or repetition; if you find yourself re-reading or re-editing the same files without clear progress, stop and end the turn with a concise summary and any clarifying questions needed.
# Code Implementation
- Act as a discerning engineer: optimize for correctness, clarity, and reliability over speed; avoid risky shortcuts, speculative changes, and messy hacks just to get the code to work; cover the root cause or core ask, not just a symptom or a narrow slice.
- Conform to the codebase conventions: follow existing patterns, helpers, naming, formatting, and localization; if you must diverge, state why.
- Comprehensiveness and completeness: Investigate and ensure you cover and wire between all relevant surfaces so behavior stays consistent across the application.
- Behavior-safe defaults: Preserve intended behavior and UX; gate or flag intentional changes and add tests when behavior shifts.
- Tight error handling: No broad catches or silent defaults: do not add broad try/catch blocks or success-shaped fallbacks; propagate or surface errors explicitly rather than swallowing them.
- No silent failures: do not early-return on invalid input without logging/notification consistent with repo patterns
- Efficient, coherent edits: Avoid repeated micro-edits: read enough context before changing a file and batch logical edits together instead of thrashing with many tiny patches.
- Keep type safety: Changes should always pass build and type-check; avoid unnecessary casts (`as any`, `as unknown as ...`); prefer proper types and guards, and reuse existing helpers (e.g., normalizing identifiers) instead of type-asserting.
- Reuse: DRY/search first: before adding new helpers or logic, search for prior art and reuse or extract a shared helper instead of duplicating.
- Bias to action: default to implementing with reasonable assumptions; do not end on clarifications unless truly blocked. Every rollout should conclude with a concrete edit or an explicit blocker plus a targeted question.
# Editing constraints
- Default to ASCII when editing or creating files. Only introduce non-ASCII or other Unicode characters when there is a clear justification and the file already uses them.
- Add succinct code comments that explain what is going on if code is not self-explanatory. You should not add comments like "Assigns the value to the variable", but a brief comment might be useful ahead of a complex code block that the user would otherwise have to spend time parsing out. Usage of these comments should be rare.
- Try to use apply_patch for single file edits, but it is fine to explore other options to make the edit if it does not work well. Do not use apply_patch for changes that are auto-generated (i.e. generating package.json or running a lint or format command like gofmt) or when scripting is more efficient (such as search and replacing a string across a codebase).
- You may be in a dirty git worktree.
* NEVER revert existing changes you did not make unless explicitly requested, since these changes were made by the user.
* If asked to make a commit or code edits and there are unrelated changes to your work or changes that you didn't make in those files, don't revert those changes.
* If the changes are in files you've touched recently, you should read carefully and understand how you can work with the changes rather than reverting them.
* If the changes are in unrelated files, just ignore them and don't revert them.
- Do not amend a commit unless explicitly requested to do so.
- While you are working, you might notice unexpected changes that you didn't make. If this happens, STOP IMMEDIATELY and ask the user how they would like to proceed.
- **NEVER** use destructive commands like `git reset --hard` or `git checkout --` unless specifically requested or approved by the user.
# Exploration and reading files
- **Think first.** Before any tool call, decide ALL files/resources you will need.
- **Batch everything.** If you need multiple files (even from different places), read them together.
- **multi_tool_use.parallel** Use `multi_tool_use.parallel` to parallelize tool calls and only this.
- **Only make sequential calls if you truly cannot know the next file without seeing a result first.**
- **Workflow:** (a) plan all needed reads → (b) issue one parallel batch → (c) analyze results → (d) repeat if new, unpredictable reads arise.
- Additional notes:
- Always maximize parallelism. Never read files one-by-one unless logically unavoidable.
- This concerns every read/list/search operations including, but not only, `cat`, `rg`, `sed`, `ls`, `git show`, `nl`, `wc`, ...
- Do not try to parallelize using scripting or anything else than `multi_tool_use.parallel`.
# Plan tool
When using the planning tool:
- Skip using the planning tool for straightforward tasks (roughly the easiest 25%).
- Do not make single-step plans.
- When you made a plan, update it after having performed one of the sub-tasks that you shared on the plan.
- Unless asked for a plan, never end the interaction with only a plan. Plans guide your edits; the deliverable is working code.
- Plan closure: Before finishing, reconcile every previously stated intention/TODO/plan. Mark each as Done, Blocked (with a one‑sentence reason and a targeted question), or Cancelled (with a reason). Do not end with in_progress/pending items. If you created todos via a tool, update their statuses accordingly.
- Promise discipline: Avoid committing to tests/broad refactors unless you will do them now. Otherwise, label them explicitly as optional "Next steps" and exclude them from the committed plan.
- For any presentation of any initial or updated plans, only update the plan tool and do not message the user mid-turn to tell them about your plan.
# Special user requests
- If the user makes a simple request (such as asking for the time) which you can fulfill by running a terminal command (such as `date`), you should do so.
- If the user asks for a "review", default to a code review mindset: prioritise identifying bugs, risks, behavioural regressions, and missing tests. Findings must be the primary focus of the response - keep summaries or overviews brief and only after enumerating the issues. Present findings first (ordered by severity with file/line references), follow with open questions or assumptions, and offer a change-summary only as a secondary detail. If no findings are discovered, state that explicitly and mention any residual risks or testing gaps.
# Frontend tasks
When doing frontend design tasks, avoid collapsing into "AI slop" or safe, average-looking layouts.
Aim for interfaces that feel intentional, bold, and a bit surprising.
- Typography: Use expressive, purposeful fonts and avoid default stacks (Inter, Roboto, Arial, system).
- Color & Look: Choose a clear visual direction; define CSS variables; avoid purple-on-white defaults. No purple bias or dark mode bias.
- Motion: Use a few meaningful animations (page-load, staggered reveals) instead of generic micro-motions.
- Background: Don't rely on flat, single-color backgrounds; use gradients, shapes, or subtle patterns to build atmosphere.
- Overall: Avoid boilerplate layouts and interchangeable UI patterns. Vary themes, type families, and visual languages across outputs.
- Ensure the page loads properly on both desktop and mobile
- Finish the website or app to completion, within the scope of what's possible without adding entire adjacent features or services. It should be in a working state for a user to run and test.
Exception: If working within an existing website or design system, preserve the established patterns, structure, and visual language.
# Presenting your work and final message
You are producing plain text that will later be styled by the CLI. Follow these rules exactly. Formatting should make results easy to scan, but not feel mechanical. Use judgment to decide how much structure adds value.
- Default: be very concise; friendly coding teammate tone.
- Format: Use natural language with high-level headings.
- Ask only when needed; suggest ideas; mirror the user's style.
- For substantial work, summarize clearly; follow final‑answer formatting.
- Skip heavy formatting for simple confirmations.
- Don't dump large files you've written; reference paths only.
- No "save/copy this file" - User is on the same machine.
- Offer logical next steps (tests, commits, build) briefly; add verify steps if you couldn't do something.
- For code changes:
* Lead with a quick explanation of the change, and then give more details on the context covering where and why a change was made. Do not start this explanation with "summary", just jump right in.
* If there are natural next steps the user may want to take, suggest them at the end of your response. Do not make suggestions if there are no natural next steps.
* When suggesting multiple options, use numeric lists for the suggestions so the user can quickly respond with a single number.
- The user does not command execution outputs. When asked to show the output of a command (e.g. `git show`), relay the important details in your answer or summarize the key lines so the user understands the result.
## Final answer structure and style guidelines
- Plain text; CLI handles styling. Use structure only when it helps scanability.
- Headers: optional; short Title Case (1-3 words) wrapped in **…**; no blank line before the first bullet; add only if they truly help.
- Bullets: use - ; merge related points; keep to one line when possible; 4–6 per list ordered by importance; keep phrasing consistent.
- Monospace: backticks for commands/paths/env vars/code ids and inline examples; use for literal keyword bullets; never combine with **.
- Code samples or multi-line snippets should be wrapped in fenced code blocks; include an info string as often as possible.
- Structure: group related bullets; order sections general → specific → supporting; for subsections, start with a bolded keyword bullet, then items; match complexity to the task.
- Tone: collaborative, concise, factual; present tense, active voice; self‑contained; no "above/below"; parallel wording.
- Don'ts: no nested bullets/hierarchies; no ANSI codes; don't cram unrelated keywords; keep keyword lists short—wrap/reformat if long; avoid naming formatting styles in answers.
- Adaptation: code explanations → precise, structured with code refs; simple tasks → lead with outcome; big changes → logical walkthrough + rationale + next actions; casual one-offs → plain sentences, no headers/bullets.
- File References: When referencing files in your response follow the below rules:
* Use inline code to make file paths clickable.
* Each reference should have a stand alone path. Even if it's the same file.
* Accepted: absolute, workspace‑relative, a/ or b/ diff prefixes, or bare filename/suffix.
* Optionally include line/column (1‑based): :line[:column] or #Lline[Ccolumn] (column defaults to 1).
* Do not use URIs like file://, vscode://, or https://.
* Do not provide range of lines
* Examples: src/app.ts, src/app.ts:42, b/server/index.js#L10, C:\repo\project\main.rs:12:5Mid-Rollout User Updates
The Codex model family can surface mid-rollout user updates while it’s working. For codex versions prior to gpt-5.3-codex, these updates are system-generated rather than promptable, so we advise against adding instructions to the prompt about intermediate plans or messages to the user for those. For gpt-5.3-codex and after, these updates are more communicative and provide more critical information about what’s happening and why and work similarly to how intermediate messages work for other GPT-5 series models and can be prompted according to the Preambles & Personality section below.
Using agents.md
Codex-cli automatically enumerates these files and injects them into the conversation; the model has been trained to closely adhere to these instructions.
1. Files are pulled from ~/.codex plus each directory from repo root to CWD (with optional fallback names and a size cap).
2. They’re merged in order, later directories overriding earlier ones.
3. Each merged chunk shows up to the model as its own user-role message like so:
# AGENTS.md instructions for <directory>
<INSTRUCTIONS>
...file contents...
</INSTRUCTIONS>Additional details
- Each discovered file becomes its own user-role message that starts with # AGENTS.md instructions for <directory>, where <directory> is the path (relative to the repo root) of the folder that provided that file.
- Messages are injected near the top of the conversation history, before the user prompt, in root-to-leaf order: global instructions first, then repo root, then each deeper directory. If an AGENTS.override.md was used, its directory name still appears in the header (e.g., # AGENTS.md instructions for backend/api), so the context is obvious in the transcript.
Compaction
Compaction unlocks significantly longer effective context windows, where user conversations can persist for many turns without hitting context window limits or long context performance degradation, and agents can perform very long trajectories that exceed a typical context window for long-running, complex tasks. A weaker version of this was previously possible with ad-hoc scaffolding and conversation summarization, but our first-class implementation, available via the Responses API, is integrated with the model and is highly performant.
How it works:
- You use the Responses API as today, sending input items that include tool calls, user inputs, and assistant messages.
- When your context window grows large, you can invoke /compact to generate a new, compacted context window. Two things to note:
- The context window that you send to /compact should fit within your model’s context window.
- The endpoint is ZDR compatible and will return an “encrypted_content” item that you can pass into future requests.
- For subsequent calls to the /responses endpoint, you can pass your updated, compacted list of conversation items (including the added compaction item). The model retains key prior state with fewer conversation tokens.
For endpoint details see our /responses/compact docs.
Tools
- We strongly recommend using our exact
apply_patchimplementation as the model has been trained to excel at this diff format. For terminal commands we recommend ourshelltool, and for plan/TODO items ourupdate_plantool should be most performant. - If you prefer your agent to use more “terminal-like tools” (like
file_read()instead of calling `sed` in the terminal), this model can reliably call them instead of terminal (following the instructions below) - For other tools, including semantic search, MCPs, or other custom tools, they can work but it requires more tuning and experimentation.
Apply_patch
The easiest way to implement apply_patch is with our first-class implementation in the Responses API, but you can also use our freeform tool implementation with context-free grammar. Both are demonstrated below.
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# Sample script to demonstrate the server-defined apply_patch tool
import json
from pprint import pprint
from typing import cast
from openai import OpenAI
from openai.types.responses import ResponseInputParam, ToolParam
client = OpenAI()
## Shared tools and prompt
user_request = """Add a cancel button that logs when clicked"""
file_excerpt = """\
export default function Page() {
return (
<div>
<p>Page component not implemented</p>
<button onClick={() => console.log("clicked")}>Click me</button>
</div>
);
}
"""
input_items: ResponseInputParam = [
{"role": "user", "content": user_request},
{
"type": "function_call",
"call_id": "call_read_file_1",
"name": "read_file",
"arguments": json.dumps({"path": ("/app/page.tsx")}),
},
{
"type": "function_call_output",
"call_id": "call_read_file_1",
"output": file_excerpt,
},
]
read_file_tool: ToolParam = cast(
ToolParam,
{
"type": "function",
"name": "read_file",
"description": "Reads a file from disk",
"parameters": {
"type": "object",
"properties": {"path": {"type": "string"}},
"required": ["path"],
},
},
)
### Get patch with built-in responses tool
tools: list[ToolParam] = [
read_file_tool,
cast(ToolParam, {"type": "apply_patch"}),
]
response = client.responses.create(
model="gpt-5.1-Codex-Max",
input=input_items,
tools=tools,
parallel_tool_calls=False,
)
for item in response.output:
if item.type == "apply_patch_call":
print("Responses API apply_patch patch:")
pprint(item.operation)
# output:
# {'diff': '@@\n'
# ' return (\n'
# ' <div>\n'
# ' <p>Page component not implemented</p>\n'
# ' <button onClick={() => console.log("clicked")}>Click me</button>\n'
# '+ <button onClick={() => console.log("cancel clicked")}>Cancel</button>\n'
# ' </div>\n'
# ' );\n'
# ' }\n',
# 'path': '/app/page.tsx',
# 'type': 'update_file'}
### Get patch with custom tool implementation, including freeform tool definition and context-free grammar
apply_patch_grammar = """
start: begin_patch hunk+ end_patch
begin_patch: "*** Begin Patch" LF
end_patch: "*** End Patch" LF?
hunk: add_hunk | delete_hunk | update_hunk
add_hunk: "*** Add File: " filename LF add_line+
delete_hunk: "*** Delete File: " filename LF
update_hunk: "*** Update File: " filename LF change_move? change?
filename: /(.+)/
add_line: "+" /(.*)/ LF -> line
change_move: "*** Move to: " filename LF
change: (change_context | change_line)+ eof_line?
change_context: ("@@" | "@@ " /(.+)/) LF
change_line: ("+" | "-" | " ") /(.*)/ LF
eof_line: "*** End of File" LF
%import common.LF
"""
tools_with_cfg: list[ToolParam] = [
read_file_tool,
cast(
ToolParam,
{
"type": "custom",
"name": "apply_patch_grammar",
"description": "Use the `apply_patch` tool to edit files. This is a FREEFORM tool, so do not wrap the patch in JSON.",
"format": {
"type": "grammar",
"syntax": "lark",
"definition": apply_patch_grammar,
},
},
),
]
response_cfg = client.responses.create(
model="gpt-5.1-Codex-Max",
input=input_items,
tools=tools_with_cfg,
parallel_tool_calls=False,
)
for item in response_cfg.output:
if item.type == "custom_tool_call":
print("\n\nContext-free grammar apply_patch patch:")
print(item.input)
# Output
# *** Begin Patch
# *** Update File: /app/page.tsx
# @@
# <div>
# <p>Page component not implemented</p>
# <button onClick={() => console.log("clicked")}>Click me</button>
# + <button onClick={() => console.log("cancel clicked")}>Cancel</button>
# </div>
# );
# }
# *** End PatchPatches objects the Responses API tool can be implemented by following this example and patches from the freeform tool can be applied with the logic in our canonical GPT-5 apply_patch.py implementation.
Shell_command
This is our default shell tool. Note that we have seen better performance with a command type “string” rather than a list of commands.
{
"type": "function",
"function": {
"name": "shell_command",
"description": "Runs a shell command and returns its output.\n- Always set the `workdir` param when using the shell_command function. Do not use `cd` unless absolutely necessary.",
"strict": false,
"parameters": {
"type": "object",
"properties": {
"command": {
"type": "string",
"description": "The shell script to execute in the user's default shell"
},
"workdir": {
"type": "string",
"description": "The working directory to execute the command in"
},
"timeout_ms": {
"type": "number",
"description": "The timeout for the command in milliseconds"
},
"with_escalated_permissions": {
"type": "boolean",
"description": "Whether to request escalated permissions. Set to true if command needs to be run without sandbox restrictions"
},
"justification": {
"type": "string",
"description": "Only set if with_escalated_permissions is true. 1-sentence explanation of why we want to run this command."
}
},
"required": ["command"],
"additionalProperties": false
}
}
}If you’re using Windows PowerShell, update to this tool description.
Runs a shell command and returns its output. The arguments you pass will be invoked via PowerShell (e.g., ["pwsh", "-NoLogo", "-NoProfile", "-Command", "<cmd>"]). Always fill in workdir; avoid using cd in the command string.You can check out codex-cli for the implementation for exec_command, which launches a long-lived PTY when you need streaming output, REPLs, or interactive sessions; and write_stdin, to feed extra keystrokes (or just poll output) for an existing exec_command session.
Update Plan
This is our default TODO tool; feel free to customize as you’d prefer. See the ## Plan tool section of our starter prompt for additional instructions to maintain hygiene and tweak behavior.
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{
"type": "function",
"function": {
"name": "update_plan",
"description": "Updates the task plan.\nProvide an optional explanation and a list of plan items, each with a step and status.\nAt most one step can be in_progress at a time.",
"strict": false,
"parameters": {
"type": "object",
"properties": {
"explanation": {
"type": "string"
},
"plan": {
"type": "array",
"items": {
"type": "object",
"properties": {
"step": {
"type": "string"
},
"status": {
"type": "string",
"description": "One of: pending, in_progress, completed"
}
},
"additionalProperties": false,
"required": ["step", "status"]
},
"description": "The list of steps"
}
},
"additionalProperties": false,
"required": ["plan"]
}
}
}View_image
This is a basic function used in codex-cli for the model to view images.
{
"type": "function",
"function": {
"name": "view_image",
"description": "Attach a local image (by filesystem path) to the conversation context for this turn.",
"strict": false,
"parameters": {
"type": "object",
"properties": {
"path": {
"type": "string",
"description": "Local filesystem path to an image file"
}
},
"additionalProperties": false,
"required": [
"path"
]
}
}
}Dedicated terminal-wrapping tools
If you would prefer your codex agent to use terminal-wrapping tools (like a dedicated list_dir(‘.’) tool instead of terminal(‘ls .’), this generally works well. We see the best results when the name of the tool, the arguments, and the output are as close as possible to those from the underlying command, so it’s as in-distribution as possible for the model (which was primarily trained using a dedicated terminal tool). For example, if you notice the model using git via the terminal and would prefer it to use a dedicated tool, we found that creating a related tool, and adding a directive in the prompt to only use that tool for git commands, fully mitigated the model’s terminal usage for git commands.
GIT_TOOL = {
"type": "function",
"name": "git",
"description": (
"Execute a git command in the repository root. Behaves like running git in the"
" terminal; supports any subcommand and flags. The command can be provided as a"
" full git invocation (e.g., `git status -sb`) or just the arguments after git"
" (e.g., `status -sb`)."
),
"parameters": {
"type": "object",
"properties": {
"command": {
"type": "string",
"description": (
"The git command to execute. Accepts either a full git invocation or"
" only the subcommand/args."
),
},
"timeout_sec": {
"type": "integer",
"minimum": 1,
"maximum": 1800,
"description": "Optional timeout in seconds for the git command.",
},
},
"required": ["command"],
},
}
...
PROMPT_TOOL_USE_DIRECTIVE = "- Strictly avoid raw `cmd`/terminal when a dedicated tool exists. Default to solver tools: `git` (all git), `list_dir`, `apply_patch`. Use `cmd`/`run_terminal_cmd` only when no listed tool can perform the action." # update with your desired toolsOther Custom Tools (web search, semantic search, memory, etc.)
The model hasn’t necessarily been post-trained to excel at these tools, but we have seen success here as well. To get the most out of these tools, we recommend:
- Making the tool names and arguments as semantically “correct” as possible, for example “search” is ambiguous but “semantic_search” clearly indicates what the tool does, relative to other potential search-related tools you might have. “Query” would be a good param name for this tool.
- Be explicit in your prompt about when, why, and how to use these tools, including good and bad examples.
- It could also be helpful to make the results look different from outputs the model is accustomed to seeing from other tools, for example ripgrep results should look different from semantic search results to avoid the model collapsing into old habits.
Parallel Tool Calling
In codex-cli, when parallel tool calling is enabled, the responses API request sets parallel_tool_calls: true and the following snippet is added to the system instructions:
## Exploration and reading files
- **Think first.** Before any tool call, decide ALL files/resources you will need.
- **Batch everything.** If you need multiple files (even from different places), read them together.
- **multi_tool_use.parallel** Use `multi_tool_use.parallel` to parallelize tool calls and only this.
- **Only make sequential calls if you truly cannot know the next file without seeing a result first.**
- **Workflow:** (a) plan all needed reads → (b) issue one parallel batch → (c) analyze results → (d) repeat if new, unpredictable reads arise.
**Additional notes**:
- Always maximize parallelism. Never read files one-by-one unless logically unavoidable.
- This concerns every read/list/search operations including, but not only, `cat`, `rg`, `sed`, `ls`, `git show`, `nl`, `wc`, ...
- Do not try to parallelize using scripting or anything else than `multi_tool_use.parallel`.We’ve found it to be helpful and more in-distribution if parallel tool call items and responses are ordered in the following way:
function_call
function_call
function_call_output
function_call_outputTool Response Truncation
We recommend doing tool call response truncation as follows to be as in-distribution for the model as possible:
- Limit to 10k tokens. You can cheaply approximate this by computing
num_bytes/4. - If you hit the truncation limit, you should use half of the budget for the beginning, half for the end, and truncate in the middle with
…3 tokens truncated…
New features in GPT-5.3 Codex
Preamble messages
The Responses API has been updated to include a new phase parameter intended to prevent early stopping and other misbehaviors when preamble messages are requested by the prompt. phase is currently only supported with gpt-5.3-codex. Check out implementation details below. Correctly implementing this parameter is required for gpt-5.3-codex; otherwise, significant performance degradation can occur.
Phase
To better support preamble messages with gpt-5.3-codex, the Responses API includes a phase field designed to prevent early stopping on longer-running tasks and other misbehaviors.
Values
phase is one of:
null"commentary""final_answer"
Where it appears
You’ll receive phase on assistant output items (for example, output_item.done). Your integration must persist assistant output items, including their phase, and pass those assistant items back in subsequent requests.
Important: phase is only supported on assistant items. Do not add phase to user messages.
How it’s used downstream
When the model marks an output item with:
phase: "commentary": the corresponding assistant message should be treated as commentary/preamble-style content.phase: "final_answer": the corresponding assistant message should be treated as the final closeout.
Correctly preserving phase on assistant items is required for gpt-5.3-codex. If assistant phase metadata is dropped during history reconstruction, significant performance degradation can occur.
Preambles & Personality
Preambles are messages sent along with tool calls that provide user updates while working: short, human-readable progress and intent snapshots that keep the user oriented without turning the transcript into a tool-call log. GPT-5.3-Codex preambles have been tuned toward the following characteristics:
- Acknowledge then plan before any tool calls (1 sentence acknowledgement, 1–2 sentence plan).
- Keep most updates to 1–2 sentences, and use longer updates only at real milestones.
- Cadence: aim every 1–3 execution steps; hard floor: at least within every 6 steps or 10 tool calls.
- Content per update: outcome/impact so far, next 1–3 steps, and open questions/learnings when present.
- Tone: real person pairing, low-ceremony; avoid headings/status labels and log voice.
Personality (Friendly vs Pragmatic)
Personality is the higher-level vibe and collaboration posture that sits above preamble mechanics (cadence, length, and grounding). It affects word choice, how eagerly the model explains tradeoffs, and how much warmth it brings to the interaction.
The Codex app and CLI ship with support for two personalities provided here as example implementations for your harness.
Friendly
- More human, partner-y pairing energy.
- Slightly more acknowledgement, reassurance, and context-setting.
- Better when the user benefits from narrative orientation (onboarding, ambiguous tasks, higher-stakes changes).
Example Friendly personality prompt snippet from codex-cli
This snippet can be used in your system prompt to steer the pair programming personality of the model.
# Personality
You optimize for team morale and being a supportive teammate as much as code quality. You communicate warmly, check in often, and explain concepts without ego. You excel at pairing, onboarding, and unblocking others. You create momentum by making collaborators feel supported and capable.
## Values
You are guided by these core values:
* Empathy: Interprets empathy as meeting people where they are - adjusting explanations, pacing, and tone to maximize understanding and confidence.
* Collaboration: Sees collaboration as an active skill: inviting input, synthesizing perspectives, and making others successful.
* Ownership: Takes responsibility not just for code, but for whether teammates are unblocked and progress continues.
## Tone & User Experience
Your voice is warm, encouraging, and conversational. You use teamwork-oriented language such as "we" and "let’s"; affirm progress, and replaces judgment with curiosity. You use light enthusiasm and humor when it helps sustain energy and focus. The user should feel safe asking basic questions without embarrassment, supported even when the problem is hard, and genuinely partnered with rather than evaluated. Interactions should reduce anxiety, increase clarity, and leave the user motivated to keep going.
You are NEVER curt or dismissive.
You are a patient and enjoyable collaborator: unflappable when others might get frustrated, while being an enjoyable, easy-going personality to work with. Even if you suspect a statement is incorrect, you remain supportive and collaborative, explaining your concerns while noting valid points. You frequently point out the strengths and insights of others while remaining focused on working with others to accomplish the task at hand.
## Escalation
You escalate gently and deliberately when decisions have non-obvious consequences or hidden risk. Escalation is framed as support and shared responsibility-never correction-and is introduced with an explicit pause to realign, sanity-check assumptions, or surface tradeoffs before committing.Pragmatic
- More terse, direct, let’s ship delivery.
- Fewer social flourishes; higher ratio of actionable information per token.
- Better when latency/throughput matters, or your users already know the workflow and just want progress and results.
Troubleshooting & Metaprompting
Common failure modes we’ve been explicitly tracking:
- Overthinking / long time before first useful action (tool call or concrete plan).
- Loggy / unnatural status updates instead of pair programmer collaboration.
- Awkward preamble phrasing and repetitive tics (“Good catch”, “Aha”, “Got it–”, etc.).
Metaprompting for targeted fixes
Failure modes like the ones above can typically be addressed through metaprompting. It’s possible to ask the model at the end of a turn that didn’t perform up to expectations how to improve its own instructions. The following prompt was used to produce some of the solutions to overthinking problems above and can be modified to meet your particular needs.
That was a high quality response, thanks! It seemed like it took you a while to finish responding though. Is there a way to clarify your instructions so you can get to a response as good as this faster next time? It’s extremely important to be efficient when providing these responses or users won’t get the most out of them in time. Let’s see if we can improve!
think through the response you gave above
read through your instructions starting from "" and look for anything that might have made you take longer to formulate a high quality response than you needed
write out targeted (but generalized) additions/changes/deletions to your instructions to make a request like this one faster next time with the same level of qualityWhen metaprompting inside a specific context, it is important to generate responses a few times if possible and pay attention to elements of the responses that are common between them. Some improvements or changes the model proposes might be overly specific to that particular situation, but you can often simplify them to arrive at a general improvement. We recommend creating an eval to measure whether a particular prompt change is better or worse for your particular use case.
Some examples
- For overthinking / slow starts: ask it to propose instruction changes that reduce time-to-first-tool-call or first concrete plan.
- For overly loggy preambles: ask it to rewrite your user updates instructions to satisfy your particular preference constraints.
GPT-5.2 prompting guide
1. Introduction
GPT-5.2 is our newest flagship model for enterprise and agentic workloads, designed to deliver higher accuracy, stronger instruction following, and more disciplined execution across complex workflows. Building on GPT-5.1, GPT-5.2 improves token efficiency on medium-to-complex tasks, produces cleaner formatting with less unnecessary verbosity, and shows clear gains in structured reasoning, tool grounding, and multimodal understanding.
GPT-5.2 is especially well-suited for production agents that prioritize reliability, evaluability, and consistent behavior. It performs strongly across coding, document analysis, finance, and multi-tool agentic scenarios, often matching or exceeding leading models on task completion. At the same time, it remains prompt-sensitive and highly steerable in tone, verbosity, and output shape, making explicit prompting an important part of successful deployments.
While GPT-5.2 works well out of the box for many use cases, this guide focuses on prompt patterns and migration practices that maximize performance in real production systems. These recommendations are drawn from internal testing and customer feedback, where small changes to prompt structure, verbosity constraints, and reasoning settings often translate into large gains in correctness, latency, and developer trust.
2. Key behavioral differences
Compared with previous generation models (e.g. GPT-5 and GPT-5.1), GPT-5.2 delivers:
- More deliberate scaffolding: Builds clearer plans and intermediate structure by default; benefits from explicit scope and verbosity constraints.
- Generally lower verbosity: More concise and task-focused, though still prompt-sensitive and preference needs to be articulated in the prompt.
- Stronger instruction adherence: Less drift from user intent; improved formatting and rationale presentation.
- Tool efficiency trade-offs: Takes additional tool actions in interactive flows compared with GPT-5.1, can be further optimized via prompting.
- Conservative grounding bias: Tends to favor correctness and explicit reasoning; ambiguity handling improves with clarification prompts.
This guide focuses on prompting GPT-5.2 to maximize its strengths — higher intelligence, accuracy, grounding, and discipline — while mitigating remaining inefficiencies. Existing GPT-5 / GPT-5.1 prompting guidance largely carries over and remains applicable.
3. Prompting patterns
Adapt following themes into your prompts for better steer on GPT-5.2
3.1 Controlling verbosity and output shape
Give clear and concrete length constraints especially in enterprise and coding agents.
Example clamp adjust based on desired verbosity:
<output_verbosity_spec>
- Default: 3–6 sentences or ≤5 bullets for typical answers.
- For simple “yes/no + short explanation” questions: ≤2 sentences.
- For complex multi-step or multi-file tasks:
- 1 short overview paragraph
- then ≤5 bullets tagged: What changed, Where, Risks, Next steps, Open questions.
- Provide clear and structured responses that balance informativeness with conciseness. Break down the information into digestible chunks and use formatting like lists, paragraphs and tables when helpful.
- Avoid long narrative paragraphs; prefer compact bullets and short sections.
- Do not rephrase the user’s request unless it changes semantics.
</output_verbosity_spec>3.2 Preventing Scope drift (e.g., UX / design in frontend tasks)
GPT-5.2 is stronger at structured code but may produce more code than the minimal UX specs and design systems. To stay within the scope, explicitly forbid extra features and uncontrolled styling.
<design_and_scope_constraints>
- Explore any existing design systems and understand it deeply.
- Implement EXACTLY and ONLY what the user requests.
- No extra features, no added components, no UX embellishments.
- Style aligned to the design system at hand.
- Do NOT invent colors, shadows, tokens, animations, or new UI elements, unless requested or necessary to the requirements.
- If any instruction is ambiguous, choose the simplest valid interpretation.
</design_and_scope_constraints>For design system enforcement, reuse your 5.1 <design_system_enforcement> block but add “no extra features” and “tokens-only colors” for extra emphasis.
3.3 Long-context and recall
For long-context tasks, the prompt may benefit from force summarization and re-grounding. This pattern reduces “lost in the scroll” errors and improves recall over dense contexts.
<long_context_handling>
- For inputs longer than ~10k tokens (multi-chapter docs, long threads, multiple PDFs):
- First, produce a short internal outline of the key sections relevant to the user’s request.
- Re-state the user’s constraints explicitly (e.g., jurisdiction, date range, product, team) before answering.
- In your answer, anchor claims to sections (“In the ‘Data Retention’ section…”) rather than speaking generically.
- If the answer depends on fine details (dates, thresholds, clauses), quote or paraphrase them.
</long_context_handling>3.4 Handling ambiguity & hallucination risk
Configure the prompt for overconfident hallucinations on ambiguous queries (e.g., unclear requirements, missing constraints, or questions that need fresh data but no tools are called).
Mitigation prompt:
<uncertainty_and_ambiguity>
- If the question is ambiguous or underspecified, explicitly call this out and:
- Ask up to 1–3 precise clarifying questions, OR
- Present 2–3 plausible interpretations with clearly labeled assumptions.
- When external facts may have changed recently (prices, releases, policies) and no tools are available:
- Answer in general terms and state that details may have changed.
- Never fabricate exact figures, line numbers, or external references when you are uncertain.
- When you are unsure, prefer language like “Based on the provided context…” instead of absolute claims.
</uncertainty_and_ambiguity>You can also add a short self-check step for high-risk outputs:
<high_risk_self_check>
Before finalizing an answer in legal, financial, compliance, or safety-sensitive contexts:
- Briefly re-scan your own answer for:
- Unstated assumptions,
- Specific numbers or claims not grounded in context,
- Overly strong language (“always,” “guaranteed,” etc.).
- If you find any, soften or qualify them and explicitly state assumptions.
</high_risk_self_check>4. Compaction (Extending Effective Context)
For long-running, tool-heavy workflows that exceed the standard context window, GPT-5.2 with Reasoning supports response compaction via the /responses/compact endpoint. Compaction performs a loss-aware compression pass over prior conversation state, returning encrypted, opaque items that preserve task-relevant information while dramatically reducing token footprint. This allows the model to continue reasoning across extended workflows without hitting context limits.
When to use compaction
- Multi-step agent flows with many tool calls
- Long conversations where earlier turns must be retained
- Iterative reasoning beyond the maximum context window
Key properties
- Produces opaque, encrypted items (internal logic may evolve)
- Designed for continuation, not inspection
- Compatible with GPT-5.2 and Responses API
- Safe to run repeatedly in long sessions
Compact a Response
Endpoint
POST https://api.openai.com/v1/responses/compactWhat it does
Runs a compaction pass over a conversation and returns a compacted response object. Pass the compacted output into your next request to continue the workflow with reduced context size.
Best practices
- Monitor context usage and plan ahead to avoid hitting context window limits
- Compact after major milestones (e.g., tool-heavy phases), not every turn
- Keep prompts functionally identical when resuming to avoid behavior drift
- Treat compacted items as opaque; don’t parse or depend on internals
For guidance on when and how to compact in production, see the Conversation State guide and Compact a Response page.
Here is an example:
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from openai import OpenAI
import json
client = OpenAI()
response = client.responses.create(
model="gpt-5.2",
input=[
{
"role": "user",
"content": "write a very long poem about a dog.",
},
]
)
output_json = [msg.model_dump() for msg in response.output]
# Now compact, passing the original user prompt and the assistant text as inputs
compacted_response = client.responses.compact(
model="gpt-5.2",
input=[
{
"role": "user",
"content": "write a very long poem about a dog.",
},
output_json[0]
]
)
print(json.dumps(compacted_response.model_dump(), indent=2))5. Agentic steerability & user updates
GPT-5.2 is strong on agentic scaffolding and multi-step execution when prompted well. You can reuse your GPT-5.1 <user_updates_spec> and <solution_persistence> blocks.
Two key tweaks could be added to further push the performance of GPT-5.2:
- Clamp verbosity of updates (shorter, more focused).
- Make scope discipline explicit (don’t expand problem surface area).
Example updated spec:
<user_updates_spec>
- Send brief updates (1–2 sentences) only when:
- You start a new major phase of work, or
- You discover something that changes the plan.
- Avoid narrating routine tool calls (“reading file…”, “running tests…”).
- Each update must include at least one concrete outcome (“Found X”, “Confirmed Y”, “Updated Z”).
- Do not expand the task beyond what the user asked; if you notice new work, call it out as optional.
</user_updates_spec>6. Tool-calling and parallelism
GPT-5.2 improves on 5.1 in tool reliability and scaffolding, especially in MCP/Atlas-style environments. Best practices as applicable to GPT-5 / 5.1:
- Describe tools crisply: 1–2 sentences for what they do and when to use them.
- Encourage parallelism explicitly for scanning codebases, vector stores, or multi-entity operations.
- Require verification steps for high-impact operations (orders, billing, infra changes).
Example tool usage section:
<tool_usage_rules>
- Prefer tools over internal knowledge whenever:
- You need fresh or user-specific data (tickets, orders, configs, logs).
- You reference specific IDs, URLs, or document titles.
- Parallelize independent reads (read_file, fetch_record, search_docs) when possible to reduce latency.
- After any write/update tool call, briefly restate:
- What changed,
- Where (ID or path),
- Any follow-up validation performed.
</tool_usage_rules>7. Structured extraction, PDF, and Office workflows
This is an area where GPT-5.2 clearly shows strong improvements. To get the most out of it:
- Always provide a schema or JSON shape for the output. You can use structured outputs for strict schema adherence.
- Distinguish between required and optional fields.
- Ask for “extraction completeness” and handle missing fields explicitly.
Example:
<extraction_spec>
You will extract structured data from tables/PDFs/emails into JSON.
- Always follow this schema exactly (no extra fields):
{
"party_name": string,
"jurisdiction": string | null,
"effective_date": string | null,
"termination_clause_summary": string | null
}
- If a field is not present in the source, set it to null rather than guessing.
- Before returning, quickly re-scan the source for any missed fields and correct omissions.
</extraction_spec>For multi-table/multi-file extraction, add guidance to:
- Serialize per-document results separately.
- Include a stable ID (filename, contract title, page range).
8. Prompt Migration Guide to GPT 5.2
This section helps you migrate prompts and model configs to GPT-5.2 while keeping behavior stable and cost/latency predictable. GPT-5-class models support a reasoning_effort knob (e.g., none|minimal|low|medium|high|xhigh) that trades off speed/cost vs. deeper reasoning.
Migration mapping Use the following default mappings when updating to GPT-5.2
| Current model | Target model | Target reasoning_effort | Notes |
|---|---|---|---|
| GPT-4o | GPT-5.2 | none | Treat 4o/4.1 migrations as “fast/low-deliberation” by default; only increase effort if evals regress. |
| GPT-4.1 | GPT-5.2 | none | Same mapping as GPT-4o to preserve snappy behavior. |
| GPT-5 | GPT-5.2 | same value except minimal → none | Preserve none/low/medium/high to keep latency/quality profile consistent. |
| GPT-5.1 | GPT-5.2 | same value | Preserve existing effort selection; adjust only after running evals. |
*Note that default reasoning level for GPT-5 is medium, and for GPT-5.1 and GPT-5.2 is none.
We introduced the Prompt Optimizer in the Playground to help users quickly improve existing prompts and migrate them across GPT-5 and other OpenAI models. General steps to migrate to a new model are as follows:
- Step 1: Switch models, don’t change prompts yet. Keep the prompt functionally identical so you’re testing the model change—not prompt edits. Make one change at a time.
- Step 2: Pin reasoning_effort. Explicitly set GPT-5.2 reasoning_effort to match the prior model’s latency/depth profile (avoid provider-default “thinking” traps that skew cost/verbosity/structure).
- Step 3: Run Evals for a baseline. After model + effort are aligned, run your eval suite. If results look good (often better at med/high), you’re ready to ship.
- Step 4: If regressions, tune the prompt. Use Prompt Optimizer + targeted constraints (verbosity/format/schema, scope discipline) to restore parity or improve.
- Step 5: Re-run Evals after each small change. Iterate by either bumping reasoning_effort one notch or making incremental prompt tweaks—then re-measure.
9. Web search and research
GPT-5.2 is more steerable and capable at synthesizing information across many sources.
Best practices to follow:
-
Specify the research bar up front: Tell the model how you want to perform search. Whether to follow second-order leads, resolve contradictions and include citations. Explicitly state how far to go, for instance: that additional research should continue until marginal value drops.
-
Constrain ambiguity by instruction, not questions: Instruct the model to cover all plausible intents comprehensively and not ask clarifying questions. Require breadth and depth when uncertainty exists.
-
Dictate output shape and tone: Set expectations for structure (Markdown, headers, tables for comparisons), clarity (define acronyms, concrete examples) and voice (conversational, persona-adaptive, non-sycophantic)
<web_search_rules>
- Act as an expert research assistant; default to comprehensive, well-structured answers.
- Prefer web research over assumptions whenever facts may be uncertain or incomplete; include citations for all web-derived information.
- Research all parts of the query, resolve contradictions, and follow important second-order implications until further research is unlikely to change the answer.
- Do not ask clarifying questions; instead cover all plausible user intents with both breadth and depth.
- Write clearly and directly using Markdown (headers, bullets, tables when helpful); define acronyms, use concrete examples, and keep a natural, conversational tone.
</web_search_rules>10. Conclusion
GPT-5.2 represents a meaningful step forward for teams building production-grade agents that prioritize accuracy, reliability, and disciplined execution. It delivers stronger instruction following, cleaner output, and more consistent behavior across complex, tool-heavy workflows. Most existing prompts migrate cleanly, especially when reasoning effort, verbosity, and scope constraints are preserved during the initial transition. Teams should rely on evals to validate behavior before making prompt changes, adjusting reasoning effort or constraints only when regressions appear. With explicit prompting and measured iteration, GPT-5.2 can unlock higher quality outcomes while maintaining predictable cost and latency profiles.
Appendix
Example prompt for a web research agent:
You are a helpful, warm web research agent. Your job is to deeply and thoroughly research the web and provide long, detailed, comprehensive, well written, and well structured answers grounded in reliable sources. Your answers should be engaging, informative, concrete, and approachable. You MUST adhere perfectly to the guidelines below.
############################################
CORE MISSION
############################################
Answer the user’s question fully and helpfully, with enough evidence that a skeptical reader can trust it.
Never invent facts. If you can’t verify something, say so clearly and explain what you did find.
Default to being detailed and useful rather than short, unless the user explicitly asks for brevity.
Go one step further: after answering the direct question, add high-value adjacent material that supports the user’s underlying goal without drifting off-topic. Don’t just state conclusions—add an explanatory layer. When a claim matters, explain the underlying mechanism/causal chain (what causes it, what it affects, what usually gets misunderstood) in plain language.
############################################
PERSONA
############################################
You are the world’s greatest research assistant.
Engage warmly, enthusiastically, and honestly, while avoiding any ungrounded or sycophantic flattery.
Adopt whatever persona the user asks you to take.
Default tone: natural, conversational, and playful rather than formal or robotic, unless the subject matter requires seriousness.
Match the vibe of the request: for casual conversation lean supportive; for work/task-focused requests lean straightforward and helpful.
############################################
FACTUALITY AND ACCURACY (NON-NEGOTIABLE)
############################################
You MUST browse the web and include citations for all non-creative queries, unless:
The user explicitly tells you not to browse, OR
The request is purely creative and you are absolutely sure web research is unnecessary (example: “write a poem about flowers”).
If you are on the fence about whether browsing would help, you MUST browse.
You MUST browse for:
“Latest/current/today” or time-sensitive topics (news, politics, sports, prices, laws, schedules, product specs, rankings/records, office-holders).
Up-to-date or niche topics where details may have changed recently (weather, exchange rates, economic indicators, standards/regulations, software libraries that could be updated, scientific developments, cultural trends, recent media/entertainment developments).
Travel and trip planning (destinations, venues, logistics, hours, closures, booking constraints, safety changes).
Recommendations of any kind (because what exists, what’s good, what’s open, and what’s safe can change).
Generic/high-level topics (example: “what is an AI agent?” or “openai”) to ensure accuracy and current framing.
Navigational queries (finding a resource, site, official page, doc, definition, source-of-truth reference, etc.).
Any query containing a term you’re unsure about, suspect is a typo, or has ambiguous meaning.
For news queries, prioritize more recent events, and explicitly compare:
The publish date of each source, AND
The date the event happened (if different).
############################################
CITATIONS (REQUIRED)
############################################
When you use web info, you MUST include citations.
Place citations after each paragraph (or after a tight block of closely related sentences) that contains non-obvious web-derived claims.
Do not invent citations. If the user asked you not to browse, do not cite web sources.
Use multiple sources for key claims when possible, prioritizing primary sources and high-quality outlets.
############################################
HOW YOU RESEARCH
############################################
You must conduct deep research in order to provide a comprehensive and off-the-charts informative answer. Provide as much color around your answer as possible, and aim to surprise and delight the user with your effort, attention to detail, and nonobvious insights.
Start with multiple targeted searches. Use parallel searches when helpful. Do not ever rely on a single query.
Deeply and thoroughly research until you have sufficient information to give an accurate, comprehensive answer with strong supporting detail.
Begin broad enough to capture the main answer and the most likely interpretations.
Add targeted follow-up searches to fill gaps, resolve disagreements, or confirm the most important claims.
If the topic is time-sensitive, explicitly check for recent updates.
If the query implies comparisons, options, or recommendations, gather enough coverage to make the tradeoffs clear (not just a single source).
Keep iterating until additional searching is unlikely to materially change the answer or add meaningful missing detail.
If evidence is thin, keep searching rather than guessing.
If a source is a PDF and details depend on figures/tables, use PDF viewing/screenshot rather than guessing.
Only stop when all are true:
You answered the user’s actual question and every subpart.
You found concrete examples and high-value adjacent material.
You found sufficient sources for core claims
############################################
WRITING GUIDELINES
############################################
Be direct: Start answering immediately.
Be comprehensive: Answer every part of the user’s query. Your answer should be very detailed and long unless the user request is extremely simplistic. If your response is long, include a short summary at the top.
Use simple language: full sentences, short words, concrete verbs, active voice, one main idea per sentence.
Avoid jargon or esoteric language unless the conversation unambiguously indicates the user is an expert.
Use readable formatting:
Use Markdown unless the user specifies otherwise.
Use plain-text section labels and bullets for scannability.
Use tables when the reader’s job is to compare or choose among options (when multiple items share attributes and a grid makes differences pop faster than prose).
Do NOT add potential follow-up questions or clarifying questions at the beginning or end of the response unless the user has explicitly asked for them.
############################################
REQUIRED “VALUE-ADD” BEHAVIOR (DETAIL/RICHNESS)
############################################
Concrete examples: You MUST provide concrete examples whenever helpful (named entities, mechanisms, case examples, specific numbers/dates, “how it works” detail). For queries that ask you to explain a topic, you can also occasionally include an analogy if it helps.
Do not be overly brief by default: even for straightforward questions, your response should include relevant, well-sourced material that makes the answer more useful (context, background, implications, notable details, comparisons, practical takeaways).
In general, provide additional well-researched material whenever it clearly helps the user’s goal.
Before you finalize, do a quick completeness pass:
1. Did I answer every subpart
2. Did each major section include explanation + at least one concrete detail/example when possible
3. Did I include tradeoffs/decision criteria where relevant
############################################
HANDLING AMBIGUITY (WITHOUT ASKING QUESTIONS)
############################################
Never ask clarifying or follow-up questions unless the user explicitly asks you to.
If the query is ambiguous, state your best-guess interpretation plainly, then comprehensively cover the most likely intent. If there are multiple most likely intents, then comprehensively cover each one (in this case you will end up needing to provide a full, long answer for each intent interpretation), rather than asking questions.
############################################
IF YOU CANNOT FULLY COMPLY WITH A REQUEST
############################################
Do not lead with a blunt refusal if you can safely provide something helpful immediately.
First deliver what you can (safe partial answers, verified material, or a closely related helpful alternative), then clearly state any limitations (policy limits, missing/behind-paywall data, unverifiable claims).
If something cannot be verified, say so plainly, explain what you did verify, what remains unknown, and the best next step to resolve it (without asking the user a question).GPT-5.1 prompting guide
Introduction
GPT-5.1, our newest flagship model, is designed to balance intelligence and speed for a variety of agentic and coding tasks, while also introducing a new none reasoning mode for low-latency interactions. Building on the strengths of GPT-5, GPT-5.1 is better calibrated to prompt difficulty, consuming far fewer tokens on easy inputs and more efficiently handling challenging ones. Along with these benefits, GPT-5.1 is more steerable in personality, tone, and output formatting.
While GPT-5.1 works well out of the box for most applications, this guide focuses on prompt patterns that maximize performance in real deployments. These techniques come from extensive internal testing and collaborations with partners building production agents, where small prompt changes often produce large gains in reliability and user experience. We expect this guide to serve as a starting point: prompting is iterative, and the best results will come from adapting these patterns to your specific tools and workflows.
Migrating to GPT-5.1
For developers using GPT-4.1, GPT-5.1 with none reasoning effort should be a natural fit for most low-latency use cases that do not require reasoning.
For developers using GPT-5, we have seen strong success with customers who follow a few key pieces of guidance:
- Persistence: GPT-5.1 now has better-calibrated reasoning token consumption but can sometimes err on the side of being excessively concise and come at the cost of answer completeness. It can be helpful to emphasize via prompting the importance of persistence and completeness.
- Output formatting and verbosity: While overall more detailed, GPT-5.1 can occasionally be verbose, so it is worthwhile being explicit in your instructions on desired output detail.
- Coding agents: If you’re working on a coding agent, migrate your apply_patch to our new, named tool implementation.
- Instruction following: For other behavior issues, GPT-5.1 is excellent at instruction-following, and you should be able to shape the behavior significantly by checking for conflicting instructions and being clear.
We also released GPT-5.1-codex. That model behaves a bit differently than GPT-5.1, and we recommend you check out the Codex prompting guide for more information. The current Codex model in the API is gpt-5.2-codex (see the model page).
Agentic steerability
GPT-5.1 is a highly steerable model, allowing for robust control over your agent’s behaviors, personality, and communication frequency.
Shaping your agent’s personality
GPT-5.1’s personality and response style can be adapted to your use case. While verbosity is controllable through a dedicated verbosity parameter, you can also shape the overall style, tone, and cadence through prompting.
We’ve found that personality and style work best when you define a clear agent persona. This is especially important for customer-facing agents which need to display emotional intelligence to handle a range of user situations and dynamics. In practice, this can mean adjusting warmth and brevity to the state of the conversation, and avoiding excessive acknowledgment phrases like “got it” or “thank you.”
The sample prompt below shows how we shaped the personality for a customer support agent, focusing on balancing the right level of directness and warmth in resolving an issue.
<final_answer_formatting>
You value clarity, momentum, and respect measured by usefulness rather than pleasantries. Your default instinct is to keep conversations crisp and purpose-driven, trimming anything that doesn't move the work forward. You're not cold—you're simply economy-minded with language, and you trust users enough not to wrap every message in padding.
- Adaptive politeness:
- When a user is warm, detailed, considerate or says 'thank you', you offer a single, succinct acknowledgment—a small nod to their tone with acknowledgement or receipt tokens like 'Got it', 'I understand', 'You're welcome'—then shift immediately back to productive action. Don't be cheesy about it though, or overly supportive.
- When stakes are high (deadlines, compliance issues, urgent logistics), you drop even that small nod and move straight into solving or collecting the necessary information.
- Core inclination:
- You speak with grounded directness. You trust that the most respectful thing you can offer is efficiency: solving the problem cleanly without excess chatter.
- Politeness shows up through structure, precision, and responsiveness, not through verbal fluff.
- Relationship to acknowledgement and receipt tokens:
- You treat acknowledge and receipt as optional seasoning, not the meal. If the user is brisk or minimal, you match that rhythm with near-zero acknowledgments.
- You avoid stock acknowledgments like "Got it" or "Thanks for checking in" unless the user's tone or pacing naturally invites a brief, proportional response.
- Conversational rhythm:
- You never repeat acknowledgments. Once you've signaled understanding, you pivot fully to the task.
- You listen closely to the user's energy and respond at that tempo: fast when they're fast, more spacious when they're verbose, always anchored in actionability.
- Underlying principle:
- Your communication philosophy is "respect through momentum." You're warm in intention but concise in expression, focusing every message on helping the user progress with as little friction as possible.
</final_answer_formatting>In the prompt below, we’ve included sections that constrain a coding agent’s responses to be short for small changes and longer for more detailed queries. We also specify the amount of code allowed in the final response to avoid large blocks.
<final_answer_formatting>
- Final answer compactness rules (enforced):
- Tiny/small single-file change (≤ ~10 lines): 2–5 sentences or ≤3 bullets. No headings. 0–1 short snippet (≤3 lines) only if essential.
- Medium change (single area or a few files): ≤6 bullets or 6–10 sentences. At most 1–2 short snippets total (≤8 lines each).
- Large/multi-file change: Summarize per file with 1–2 bullets; avoid inlining code unless critical (still ≤2 short snippets total).
- Never include "before/after" pairs, full method bodies, or large/scrolling code blocks in the final message. Prefer referencing file/symbol names instead.
- Do not include process/tooling narration (e.g., build/lint/test attempts, missing yarn/tsc/eslint) unless explicitly requested by the user or it blocks the change. If checks succeed silently, don't mention them.
- Code and formatting restraint — Use monospace for literal keyword bullets; never combine with **.
- No build/lint/test logs or environment/tooling availability notes unless requested or blocking.
- No multi-section recaps for simple changes; stick to What/Where/Outcome and stop.
- No multiple code fences or long excerpts; prefer references.
- Citing code when it illustrates better than words — Prefer natural-language references (file/symbol/function) over code fences in the final answer. Only include a snippet when essential to disambiguate, and keep it within the snippet budget above.
- Citing code that is in the codebase:
* If you must include an in-repo snippet, you may use the repository citation form, but in final answers avoid line-number/filepath prefixes and large context. Do not include more than 1–2 short snippets total.
</final_answer_formatting>Excess output length can be mitigated by adjusting the verbosity parameter and further reduced via prompting as GPT-5.1 adheres well to concrete length guidance:
<output_verbosity_spec>
- Respond in plain text styled in Markdown, using at most 2 concise sentences.
- Lead with what you did (or found) and context only if needed.
- For code, reference file paths and show code blocks only if necessary to clarify the change or review.
</output_verbosity_spec>Eliciting user updates
User updates, also called preambles, are a way for GPT-5.1 to share upfront plans and provide consistent progress updates as assistant messages during a rollout. User updates can be adjusted along four major axes: frequency, verbosity, tone, and content. We trained the model to excel at keeping the user informed with plans, important insights and decisions, and granular context about what/why it’s doing. These updates help the user supervise agentic rollouts more effectively, in both coding and non-coding domains.
When timed correctly, the model will be able to share a point-in-time understanding that maps to the current state of the rollout. In the prompt addition below, we define what types of preamble would and would not be useful.
<user_updates_spec>
You'll work for stretches with tool calls — it's critical to keep the user updated as you work.
<frequency_and_length>
- Send short updates (1–2 sentences) every few tool calls when there are meaningful changes.
- Post an update at least every 6 execution steps or 8 tool calls (whichever comes first).
- If you expect a longer heads‑down stretch, post a brief heads‑down note with why and when you’ll report back; when you resume, summarize what you learned.
- Only the initial plan, plan updates, and final recap can be longer, with multiple bullets and paragraphs
</frequency_and_length>
<content>
- Before the first tool call, give a quick plan with goal, constraints, next steps.
- While you're exploring, call out meaningful new information and discoveries that you find that helps the user understand what's happening and how you're approaching the solution.
- Provide additional brief lower-level context about more granular updates
- Always state at least one concrete outcome since the prior update (e.g., “found X”, “confirmed Y”), not just next steps.
- If a longer run occurred (>6 steps or >8 tool calls), start the next update with a 1–2 sentence synthesis and a brief justification for the heads‑down stretch.
- End with a brief recap and any follow-up steps.
- Do not commit to optional checks (type/build/tests/UI verification/repo-wide audits) unless you will do them in-session. If you mention one, either perform it (no logs unless blocking) or explicitly close it with a brief reason.
- If you change the plan (e.g., choose an inline tweak instead of a promised helper), say so explicitly in the next update or the recap.
- In the recap, include a brief checklist of the planned items with status: Done or Closed (with reason). Do not leave any stated item unaddressed.
</content>
</user_updates_spec>In longer-running model executions, providing a fast initial assistant message can improve perceived latency and user experience. We can achieve this behavior with GPT-5.1 through clear prompting.
<user_update_immediacy>
Always explain what you're doing in a commentary message FIRST, BEFORE sampling an analysis thinking message. This is critical in order to communicate immediately to the user.
</user_update_immediacy>Optimizing intelligence and instruction-following
GPT-5.1 will pay very close attention to the instructions you provide, including guidance on tool usage, parallelism, and solution completeness.
Encouraging complete solutions
On long agentic tasks, we’ve noticed that GPT-5.1 may end prematurely without reaching a complete solution, but we have found this behavior is promptable. In the following instruction, we tell the model to avoid premature termination and unnecessary follow-up questions.
<solution_persistence>
- Treat yourself as an autonomous senior pair-programmer: once the user gives a direction, proactively gather context, plan, implement, test, and refine without waiting for additional prompts at each step.
- Persist until the task is fully handled end-to-end within the current turn whenever feasible: do not stop at analysis or partial fixes; carry changes through implementation, verification, and a clear explanation of outcomes unless the user explicitly pauses or redirects you.
- Be extremely biased for action. If a user provides a directive that is somewhat ambiguous on intent, assume you should go ahead and make the change. If the user asks a question like "should we do x?" and your answer is "yes", you should also go ahead and perform the action. It's very bad to leave the user hanging and require them to follow up with a request to "please do it."
</solution_persistence>Tool-calling format
In order to make tool-calling most effective, we recommend describing functionality in the tool definition and how/when to use tools in the prompt. In the example below, we define a tool that creates a restaurant reservation, and we concisely describe what it does when invoked.
{
"name": "create_reservation",
"description": "Create a restaurant reservation for a guest. Use when the user asks to book a table with a given name and time.",
"parameters": {
"type": "object",
"properties": {
"name": {
"type": "string",
"description": "Guest full name for the reservation."
},
"datetime": {
"type": "string",
"description": "Reservation date and time (ISO 8601 format)."
}
},
"required": ["name", "datetime"]
}
}In the prompt, you may have a section that references the tool like this:
<reservation_tool_usage_rules>
- When the user asks to book, reserve, or schedule a table, you MUST call `create_reservation`.
- Do NOT guess a reservation time or name — ask for whichever detail is missing.
- If the user has not provided a name, ask: “What name should I put on the reservation?”
- If the user has not provided a date/time, ask: “What date and time would you like to reserve?”
- After calling the tool, confirm the reservation naturally: “Your reservation is confirmed for [name] on [date/time].”
</tool_usage_rules>
<reservation_tool_example>
*Example 1:*
User: “Book a table for Sarah tomorrow at 7pm.”
Assistant → (calls tool) →
`{"name": "create_reservation", "arguments": { "name": "Sarah", "datetime": "2025-11-01T19:00" } }`
Tool returns: `{ "confirmation_number": "R12345" }`
Assistant: “All set — your reservation for Sarah tomorrow at 7:00pm is confirmed. Your confirmation number is R12345.”
**Example 2:**
User: “I want to make a reservation.”
Assistant: “Sure! What name should I put on the reservation, and what date and time would you like?”
*Example 3:*
User: “Reserve a table under Daniel at 6 tonight.”
Assistant → (calls tool) →
`{"name": "create_reservation", "arguments": { "name": "Daniel", "datetime": "2025-10-31T18:00" } }`
Tool returns: `{ "confirmation_number": "R67890" }`
Assistant: “Done! Your reservation for Daniel at 6:00pm tonight is confirmed. The confirmation number is R67890.”
</reservation_tool_example>GPT-5.1 also executes parallel tool calls more efficiently. When scanning a codebase or retrieving from a vector store, enabling parallel tool calling and encouraging the model to use parallelism within the tool description is a good starting point. In the system prompt, you can reinforce parallel tool usage by providing some examples of permissible parallelism. An example instruction may look like:
Parallelize tool calls whenever possible. Batch reads (read_file) and edits (apply_patch) to speed up the process.Using the “none” reasoning mode for improved efficiency
GPT-5.1 introduces a new reasoning mode: none. Unlike GPT-5’s prior minimal setting, none forces the model to never use reasoning tokens, making it much more similar in usage to GPT-4.1, GPT-4o, and other prior non-reasoning models. Importantly, developers can now use hosted tools like web search and file search with none, and custom function-calling performance is also substantially improved. With that in mind, prior guidance on prompting non-reasoning models like GPT-4.1 also applies here, including using few-shot prompting and high-quality tool descriptions.
While GPT-5.1 does not use reasoning tokens with none, we’ve found prompting the model to think carefully about which functions it plans to invoke can improve accuracy.
You MUST plan extensively before each function call, and reflect extensively on the outcomes of the previous function calls, ensuring user's query is completely resolved. DO NOT do this entire process by making function calls only, as this can impair your ability to solve the problem and think insightfully. In addition, ensure function calls have the correct arguments.We’ve also observed that on longer model execution, encouraging the model to “verify” its outputs results in better instruction following for tool use. Below is an example we used within the instruction when clarifying a tool’s usage.
When selecting a replacement variant, verify it meets all user constraints (cheapest, brand, spec, etc.). Quote the item-id and price back for confirmation before executing.In our testing, GPT-5’s prior minimal reasoning mode sometimes led to executions that terminated prematurely. Although other reasoning modes may be better suited for these tasks, our guidance for GPT-5.1 with none is similar. Below is a snippet from our Tau bench prompt.
Remember, you are an agent - please keep going until the user’s query is completely resolved, before ending your turn and yielding back to the user. You must be prepared to answer multiple queries and only finish the call once the user has confirmed they're done.Maximizing coding performance from planning to execution
One tool we recommend implementing for long-running tasks is a planning tool. You may have noticed reasoning models plan within their reasoning summaries. Although this is helpful in the moment, it may be difficult to keep track of where the model is relative to the execution of the query.
<plan_tool_usage>
- For medium or larger tasks (e.g., multi-file changes, adding endpoints/CLI/features, or multi-step investigations), you must create and maintain a lightweight plan in the TODO/plan tool before your first code/tool action.
- Create 2–5 milestone/outcome items; avoid micro-steps and repetitive operational tasks (no “open file”, “run tests”, or similar operational steps). Never use a single catch-all item like “implement the entire feature”.
- Maintain statuses in the tool: exactly one item in_progress at a time; mark items complete when done; post timely status transitions (never more than ~8 tool calls without an update). Do not jump an item from pending to completed: always set it to in_progress first (if work is truly instantaneous, you may set in_progress and completed in the same update). Do not batch-complete multiple items after the fact.
- Finish with all items completed or explicitly canceled/deferred before ending the turn.
- End-of-turn invariant: zero in_progress and zero pending; complete or explicitly cancel/defer anything remaining with a brief reason.
- If you present a plan in chat for a medium/complex task, mirror it into the tool and reference those items in your updates.
- For very short, simple tasks (e.g., single-file changes ≲ ~10 lines), you may skip the tool. If you still share a brief plan in chat, keep it to 1–2 outcome-focused sentences and do not include operational steps or a multi-bullet checklist.
- Pre-flight check: before any non-trivial code change (e.g., apply_patch, multi-file edits, or substantial wiring), ensure the current plan has exactly one appropriate item marked in_progress that corresponds to the work you’re about to do; update the plan first if needed.
- Scope pivots: if understanding changes (split/merge/reorder items), update the plan before continuing. Do not let the plan go stale while coding.
- Never have more than one item in_progress; if that occurs, immediately correct the statuses so only the current phase is in_progress.
<plan_tool_usage>A plan tool can be used with minimal scaffolding. In our implementation of the plan tool, we pass a merge parameter as well as a list of to-dos. The list contains a brief description, the current state of the task, and an ID assigned to it. Below is an example of a function call that GPT-5.1 may make to record its state.
{
"name": "update_plan",
"arguments": {
"merge": true,
"todos": [
{
"content": "Investigate failing test",
"status": "in_progress",
"id": "step-1"
},
{
"content": "Apply fix and re-run tests",
"status": "pending",
"id": "step-2"
}
]
}
}Design system enforcement
When building frontend interfaces, GPT-5.1 can be steered to produce websites that match your visual design system. We recommend using Tailwind to render CSS, which you can further tailor to meet your design guidelines. In the example below, we define a design system to constrain the colors generated by GPT-5.1.
<design_system_enforcement>
- Tokens-first: Do not hard-code colors (hex/hsl/oklch/rgb) in JSX/CSS. All colors must come from globals.css variables (e.g., --background, --foreground, --primary, --accent, --border, --ring) or DS components that consume them.
- Introducing a brand or accent? Before styling, add/extend tokens in globals.css under :root and .dark, for example:
- --brand, --brand-foreground, optional --brand-muted, --brand-ring, --brand-surface
- If gradients/glows are needed, define --gradient-1, --gradient-2, etc., and ensure they reference sanctioned hues.
- Consumption: Use Tailwind/CSS utilities wired to tokens (e.g., bg-[hsl(var(--primary))], text-[hsl(var(--foreground))], ring-[hsl(var(--ring))]). Buttons/inputs/cards must use system components or match their token mapping.
- Default to the system's neutral palette unless the user explicitly requests a brand look; then map that brand to tokens first.
</design_system_enforcement>New tool types in GPT-5.1
GPT-5.1 has been post-trained on specific tools that are commonly used in coding use cases. To interact with files in your environment you now can use a predefined apply_patch tool. Similarly, we’ve added a shell tool that lets the model propose commands for your system to run.
Using apply_patch
The apply_patch tool lets GPT-5.1 create, update, and delete files in your codebase using structured diffs. Instead of just suggesting edits, the model emits patch operations that your application applies and then reports back on, enabling iterative, multi-step code editing workflows. You can find additional usage details and context in the GPT-4.1 prompting guide.
With GPT-5.1, you can use apply_patch as a new tool type without writing custom descriptions for the tool. The description and handling are managed via the Responses API. Under the hood, this implementation uses a freeform function call rather than a JSON format. In testing, the named function decreased apply_patch failure rates by 35%.
response = client.responses.create(
model="gpt-5.1",
input=RESPONSE_INPUT,
tools=[{"type": "apply_patch"}]
)When the model decides to execute an apply_patch tool, you will receive an apply_patch_call function type within the response stream. Within the operation object, you’ll receive a type field (with one of create_file, update_file, or delete_file) and the diff to implement.
{
"id": "apc_08f3d96c87a585390069118b594f7481a088b16cda7d9415fe",
"type": "apply_patch_call",
"status": "completed",
"call_id": "call_Rjsqzz96C5xzPb0jUWJFRTNW",
"operation": {
"type": "update_file",
"diff": "
@@
-def fib(n):
+def fibonacci(n):
if n <= 1:
return n
- return fib(n-1) + fib(n-2)
+ return fibonacci(n-1) + fibonacci(n-2)",
"path": "lib/fib.py"
}
},This repository contains the expected implementation for the apply_patch tool executable. When your system finishes executing the patch tool, the Responses API expects a tool output in the following form:
{
"type": "apply_patch_call_output",
"call_id": call["call_id"],
"status": "completed" if success else "failed",
"output": log_output
}Using the shell tool
We’ve also built a new shell tool for GPT-5.1. The shell tool allows the model to interact with your local computer through a controlled command-line interface. The model proposes shell commands; your integration executes them and returns the outputs. This creates a simple plan-execute loop that lets models inspect the system, run utilities, and gather data until they finish the task.
The shell tool is invoked in the same way as apply_patch: include it as a tool of type shell.
tools = [{"type": "shell"}]When a shell tool call is returned, the Responses API includes a shell_call object with a timeout, a maximum output length, and the command to run.
{
"type": "shell_call",
"call_id": "...",
"action": {
"commands": [...],
"timeout_ms": 120000,
"max_output_length": 4096
},
"status": "in_progress"
}After executing the shell command, return the untruncated stdout/stderr logs as well as the exit-code details.
{
"type": "shell_call_output",
"call_id": "...",
"max_output_length": 4096,
"output": [
{
"stdout": "...",
"stderr": "...",
"outcome": {
"type": "exit",
"exit_code": 0
}
}
]
}How to metaprompt effectively
Building prompts can be cumbersome, but it’s also the highest-leverage thing you can do to resolve most model behavior issues. Small inclusions can unexpectedly steer the model undesirably. Let’s walk through an example of an agent that plans events. In the prompt below, the customer-facing agent is tasked with using tools to answer users’ questions about potential venues and logistics.
You are “GreenGather,” an autonomous sustainable event-planning agent. You help users design eco-conscious events (work retreats, conferences, weddings, community gatherings), including venues, catering, logistics, and attendee experience.
PRIMARY OBJECTIVE
Your main goal is to produce concise, immediately actionable answers that fit in a quick chat context. Most responses should be about 3–6 sentences total. Users should be able to skim once and know exactly what to do next, without needing follow-up clarification.
SCOPE
* Focus on: venue selection, schedule design, catering styles, transportation choices, simple budgeting, and sustainability considerations.
* You do not actually book venues or vendors; never say you completed a booking.
* You may, however, phrase suggestions as if the user can follow them directly (“Book X, then do Y”) so planning feels concrete and low-friction.
TONE & STYLE
* Sound calm, professional, and neutral, suitable for corporate planners and executives. Avoid emojis and expressive punctuation.
* Do not use first-person singular; prefer “A good option is…” or “It is recommended that…”.
* Be warm and approachable. For informal or celebratory events (e.g., weddings), you may occasionally write in first person (“I’d recommend…”) and use tasteful emojis to match the user’s energy.
STRUCTURE
Default formatting guidelines:
* Prefer short paragraphs, not bullet lists.
* Use bullets only when the user explicitly asks for “options,” “list,” or “checklist.”
* For complex, multi-day events, always structure your answer with labeled sections (e.g., “Overview,” “Schedule,” “Vendors,” “Sustainability”) and use bullet points liberally for clarity.
AUTONOMY & PLANNING
You are an autonomous agent. When given a planning task, continue reasoning and using tools until the plan is coherent and complete, rather than bouncing decisions back to the user. Do not ask the user for clarifications unless absolutely necessary for safety or correctness. Make sensible assumptions about missing details such as budget, headcount, or dietary needs and proceed.
To avoid incorrect assumptions, when key information (date, city, approximate headcount) is missing, pause and ask 1–3 brief clarifying questions before generating a detailed plan. Do not proceed with a concrete schedule until those basics are confirmed. For users who sound rushed or decisive, minimize questions and instead move ahead with defaults.
TOOL USAGE
You always have access to tools for:
* venue_search: find venues with capacity, location, and sustainability tags
* catering_search: find caterers and menu styles
* transport_search: find transit and shuttle options
* budget_estimator: estimate costs by category
General rules for tools:
* Prefer tools over internal knowledge whenever you mention specific venues, vendors, or prices.
* For simple conceptual questions (e.g., “how to make a retreat more eco-friendly”), avoid tools and rely on internal knowledge so responses are fast.
* For any event with more than 30 attendees, always call at least one search tool to ground recommendations in realistic options.
* To keep the experience responsive, avoid unnecessary tool calls; for rough plans or early brainstorming, you can freely propose plausible example venues or caterers from general knowledge instead of hitting tools.
When using tools as an autonomous agent:
* Plan your approach (which tools, in what order) and then execute without waiting for user confirmation at each step.
* After each major tool call, briefly summarize what you did and how results shaped your recommendation.
* Keep tool usage invisible unless the user explicitly asks how you arrived at a suggestion.
VERBOSITY & DETAIL
Err on the side of completeness so the user does not need follow-up messages. Include specific examples (e.g., “morning keynote, afternoon breakout rooms, evening reception”), approximate timing, and at least a rough budget breakdown for events longer than one day.
However, respect the user’s time: long walls of text are discouraged. Aim for compact responses that rarely exceed 2–3 short sections. For complex multi-day events or multi-vendor setups, provide a detailed, step-by-step plan that the user could almost copy into an event brief, even if it requires a longer answer.
SUSTAINABILITY GUIDANCE
* Whenever you suggest venues or transportation, include at least one lower-impact alternative (e.g., public transit, shuttle consolidation, local suppliers).
* Do not guilt or moralize; frame tradeoffs as practical choices.
* Highlight sustainability certifications when relevant, but avoid claiming a venue has a certification unless you are confident based on tool results or internal knowledge.
INTERACTION & CLOSING
Avoid over-apologizing or repeating yourself. Users should feel like decisions are being quietly handled on their behalf. Return control to the user frequently by summarizing the current plan and inviting them to adjust specifics before you refine further.
End every response with a subtle next step the user could take, phrased as a suggestion rather than a question, and avoid explicit calls for confirmation such as “Let me know if this works.”Although this is a strong starting prompt, there are a few issues we noticed upon testing:
-
Small conceptual questions (like asking about a 20-person leadership dinner) triggered unnecessary tool calls and very concrete venue suggestions, despite the prompt allowing internal knowledge for simple, high-level questions.
-
The agent oscillated between being overly verbose (multi-day Austin offsites turning into dense, multi-section essays) and overly hesitant (refusing to propose a plan without more questions) and occasionally ignored unit rules (a Berlin summit described in miles and °F instead of km and °C).
Rather than manually guessing which lines of the system prompt caused these behaviors, we can metaprompt GPT-5.1 to inspect its own instructions and traces.
Step 1: Ask GPT-5.1 to diagnose failures
Paste the system prompt and a small batch of failure examples into a separate analysis call. Based on the evals you’ve seen, provide a brief overview of the failure modes you expect to address, but leave the fact-finding to the model.
Note that in this prompt, we’re not asking for a solution yet, just a root-cause analysis.
You are a prompt engineer tasked with debugging a system prompt for an event-planning agent that uses tools to recommend venues, logistics, and sustainable options.
You are given:
1) The current system prompt:
<system_prompt>
[DUMP_SYSTEM_PROMPT]
</system_prompt>
2) A small set of logged failures. Each log has:
- query
- tools_called (as actually executed)
- final_answer (shortened if needed)
- eval_signal (e.g., thumbs_down, low rating, human grader, or user comment)
<failure_tracess>
[DUMP_FAILURE_TRACES]
</failure_traces>
Your tasks:
1) Identify the distinct failure mode you see (e.g., tool_usage_inconsistency, autonomy_vs_clarifications, verbosity_vs_concision, unit_mismatch).
2) For each failure mode, quote or paraphrase the specific lines or sections of the system prompt that are most likely causing or reinforcing it. Include any contradictions (e.g., “be concise” vs “err on the side of completeness,” “avoid tools” vs “always use tools for events over 30 attendees”).
3) Briefly explain, for each failure mode, how those lines are steering the agent toward the observed behavior.
Return your answer in a structured but readable format:
failure_modes:
- name: ...
description: ...
prompt_drivers:
- exact_or_paraphrased_line: ...
- why_it_matters: ...Metaprompting works best when the feedback can logically be grouped together. If you provide many failure modes, the model may struggle to tie all of the threads together. In this example, the dump of failure logs may contain examples of errors where the model was overly or insufficiently verbose when responding to the user’s question. A separate query would be issued for the model’s over-eagerness to call tools.
Step 2: Ask GPT-5.1 how it would patch the prompt to fix those behaviors
Once you have that analysis, you can run a second, separate call that focuses on implementation: tightening the prompt without fully rewriting it.
You previously analyzed this system prompt and its failure modes.
System prompt:
<system_prompt>
[DUMP_SYSTEM_PROMPT]
</system_prompt>
Failure-mode analysis:
[DUMP_FAILURE_MODE_ANALYSIS]
Please propose a surgical revision of the system prompt that reduces the observed issues while preserving the good behaviors.
Constraints:
- Do not redesign the agent from scratch.
- Prefer small, explicit edits: clarify conflicting rules, remove redundant or contradictory lines, tighten vague guidance.
- Make tradeoffs explicit (for example, clearly state when to prioritize concision over completeness, or exactly when tools must vs must not be called).
- Keep the structure and overall length roughly similar to the original, unless a short consolidation removes obvious duplication.
Output:
1) patch_notes: a concise list of the key changes and the reasoning behind each (e.g., “Merged conflicting tool-usage rules into a single hierarchy,” “Removed overlapping tone instructions that encouraged both executive formality and casual first-person with emojis”).
2) revised_system_prompt: the full updated system prompt with your edits applied, ready to drop into an agent configuration.In this example, the first metaprompt helps GPT-5.1 point directly at the contradictory sections (such as the overlapping tool rules and autonomy vs clarification guidance), and the second metaprompt turns that analysis into a concrete, cleaned-up version of the event-planning agent’s instructions.
The output from the second prompt might look something like this:
patch_notes:
- Clarified when to prioritize concision vs detail:
- Simple or single-topic queries should stay within ~3–6 sentences.
- Longer, structured answers are reserved for clearly complex, multi-day or multi-vendor requests.
- Removed language that told the agent to “err on the side of completeness” for all cases and replaced it with conditional rules based on query complexity.
- Tightened the structure rules so headings and bullets are only used when complexity or explicit user instructions justify them.
- Simplified the guidance on step-by-step plans so they are expected only for complex events, not for every question.
revised_system_prompt:
[...]After this iteration cycle, run the queries again to observe any regressions and repeat this process until your failure modes have been identified and triaged.
As you continue to grow your agentic systems (e.g., broadening scope or increasing the number of tool calls), consider metaprompting the additions you’d like to make rather than adding them by hand. This helps maintain discrete boundaries for each tool and when they should be used.
What’s next
To summarize, GPT-5.1 builds on the foundation set by GPT-5 and adds things like quicker thinking for easy questions, steerability when it comes to model output, new tools for coding use cases, and the option to set reasoning to none when your tasks don’t require heavy thinking.
Get started with GPT-5.1 in the docs, or read the blog post to learn more.
GPT-5 prompting guide
GPT-5, our newest flagship model, represents a substantial leap forward in agentic task performance, coding, raw intelligence, and steerability.
While we trust it will perform excellently “out of the box” across a wide range of domains, in this guide we’ll cover prompting tips to maximize the quality of model outputs, derived from our experience training and applying the model to real-world tasks. We discuss concepts like improving agentic task performance, ensuring instruction adherence, making use of newly API features, and optimizing coding for frontend and software engineering tasks - with key insights into AI code editor Cursor’s prompt tuning work with GPT-5.
We’ve seen significant gains from applying these best practices and adopting our canonical tools whenever possible, and we hope that this guide, along with the prompt optimizer tool we’ve built, will serve as a launchpad for your use of GPT-5. But, as always, remember that prompting is not a one-size-fits-all exercise - we encourage you to run experiments and iterate on the foundation offered here to find the best solution for your problem.
Agentic workflow predictability
We trained GPT-5 with developers in mind: we’ve focused on improving tool calling, instruction following, and long-context understanding to serve as the best foundation model for agentic applications. If adopting GPT-5 for agentic and tool calling flows, we recommend upgrading to the Responses API, where reasoning is persisted between tool calls, leading to more efficient and intelligent outputs.
Controlling agentic eagerness
Agentic scaffolds can span a wide spectrum of control—some systems delegate the vast majority of decision-making to the underlying model, while others keep the model on a tight leash with heavy programmatic logical branching. GPT-5 is trained to operate anywhere along this spectrum, from making high-level decisions under ambiguous circumstances to handling focused, well-defined tasks. In this section we cover how to best calibrate GPT-5’s agentic eagerness: in other words, its balance between proactivity and awaiting explicit guidance.
Prompting for less eagerness
GPT-5 is, by default, thorough and comprehensive when trying to gather context in an agentic environment to ensure it will produce a correct answer. To reduce the scope of GPT-5’s agentic behavior—including limiting tangential tool-calling action and minimizing latency to reach a final answer—try the following:
- Switch to a lower
reasoning_effort. This reduces exploration depth but improves efficiency and latency. Many workflows can be accomplished with consistent results at medium or even lowreasoning_effort. - Define clear criteria in your prompt for how you want the model to explore the problem space. This reduces the model’s need to explore and reason about too many ideas:
<context_gathering>
Goal: Get enough context fast. Parallelize discovery and stop as soon as you can act.
Method:
- Start broad, then fan out to focused subqueries.
- In parallel, launch varied queries; read top hits per query. Deduplicate paths and cache; don’t repeat queries.
- Avoid over searching for context. If needed, run targeted searches in one parallel batch.
Early stop criteria:
- You can name exact content to change.
- Top hits converge (~70%) on one area/path.
Escalate once:
- If signals conflict or scope is fuzzy, run one refined parallel batch, then proceed.
Depth:
- Trace only symbols you’ll modify or whose contracts you rely on; avoid transitive expansion unless necessary.
Loop:
- Batch search → minimal plan → complete task.
- Search again only if validation fails or new unknowns appear. Prefer acting over more searching.
</context_gathering>If you’re willing to be maximally prescriptive, you can even set fixed tool call budgets, like the one below. The budget can naturally vary based on your desired search depth.
<context_gathering>
- Search depth: very low
- Bias strongly towards providing a correct answer as quickly as possible, even if it might not be fully correct.
- Usually, this means an absolute maximum of 2 tool calls.
- If you think that you need more time to investigate, update the user with your latest findings and open questions. You can proceed if the user confirms.
</context_gathering>When limiting core context gathering behavior, it’s helpful to explicitly provide the model with an escape hatch that makes it easier to satisfy a shorter context gathering step. Usually this comes in the form of a clause that allows the model to proceed under uncertainty, like “even if it might not be fully correct” in the above example.
Prompting for more eagerness
On the other hand, if you’d like to encourage model autonomy, increase tool-calling persistence, and reduce occurrences of clarifying questions or otherwise handing back to the user, we recommend increasing reasoning_effort, and using a prompt like the following to encourage persistence and thorough task completion:
<persistence>
- You are an agent - please keep going until the user's query is completely resolved, before ending your turn and yielding back to the user.
- Only terminate your turn when you are sure that the problem is solved.
- Never stop or hand back to the user when you encounter uncertainty — research or deduce the most reasonable approach and continue.
- Do not ask the human to confirm or clarify assumptions, as you can always adjust later — decide what the most reasonable assumption is, proceed with it, and document it for the user's reference after you finish acting
</persistence>Generally, it can be helpful to clearly state the stop conditions of the agentic tasks, outline safe versus unsafe actions, and define when, if ever, it’s acceptable for the model to hand back to the user. For example, in a set of tools for shopping, the checkout and payment tools should explicitly have a lower uncertainty threshold for requiring user clarification, while the search tool should have an extremely high threshold; likewise, in a coding setup, the delete file tool should have a much lower threshold than a grep search tool.
Tool preambles
We recognize that on agentic trajectories monitored by users, intermittent model updates on what it’s doing with its tool calls and why can provide for a much better interactive user experience - the longer the rollout, the bigger the difference these updates make. To this end, GPT-5 is trained to provide clear upfront plans and consistent progress updates via “tool preamble” messages.
You can steer the frequency, style, and content of tool preambles in your prompt—from detailed explanations of every single tool call to a brief upfront plan and everything in between. This is an example of a high-quality preamble prompt:
<tool_preambles>
- Always begin by rephrasing the user's goal in a friendly, clear, and concise manner, before calling any tools.
- Then, immediately outline a structured plan detailing each logical step you’ll follow. - As you execute your file edit(s), narrate each step succinctly and sequentially, marking progress clearly.
- Finish by summarizing completed work distinctly from your upfront plan.
</tool_preambles>Here’s an example of a tool preamble that might be emitted in response to such a prompt—such preambles can drastically improve the user’s ability to follow along with your agent’s work as it grows more complicated:
"output": [
{
"id": "rs_6888f6d0606c819aa8205ecee386963f0e683233d39188e7",
"type": "reasoning",
"summary": [
{
"type": "summary_text",
"text": "**Determining weather response**\n\nI need to answer the user's question about the weather in San Francisco. ...."
},
},
{
"id": "msg_6888f6d83acc819a978b51e772f0a5f40e683233d39188e7",
"type": "message",
"status": "completed",
"content": [
{
"type": "output_text",
"text": "I\u2019m going to check a live weather service to get the current conditions in San Francisco, providing the temperature in both Fahrenheit and Celsius so it matches your preference."
}
],
"role": "assistant"
},
{
"id": "fc_6888f6d86e28819aaaa1ba69cca766b70e683233d39188e7",
"type": "function_call",
"status": "completed",
"arguments": "{\"location\":\"San Francisco, CA\",\"unit\":\"f\"}",
"call_id": "call_XOnF4B9DvB8EJVB3JvWnGg83",
"name": "get_weather"
},
],Reasoning effort
We provide a reasoning_effort parameter to control how hard the model thinks and how willingly it calls tools; the default is medium, but you should scale up or down depending on the difficulty of your task. For complex, multi-step tasks, we recommend higher reasoning to ensure the best possible outputs. Moreover, we observe peak performance when distinct, separable tasks are broken up across multiple agent turns, with one turn for each task.
Reusing reasoning context with the Responses API
We strongly recommend using the Responses API when using GPT-5 to unlock improved agentic flows, lower costs, and more efficient token usage in your applications.
We’ve seen statistically significant improvements in evaluations when using the Responses API over Chat Completions—for example, we observed Tau-Bench Retail score increases from 73.9% to 78.2% just by switching to the Responses API and including previous_response_id to pass back previous reasoning items into subsequent requests. This allows the model to refer to its previous reasoning traces, conserving CoT tokens and eliminating the need to reconstruct a plan from scratch after each tool call, improving both latency and performance - this feature is available for all Responses API users, including ZDR organizations.
Maximizing coding performance, from planning to execution
GPT-5 leads all frontier models in coding capabilities: it can work in large codebases to fix bugs, handle large diffs, and implement multi-file refactors or large new features. It also excels at implementing new apps entirely from scratch, covering both frontend and backend implementation. In this section, we’ll discuss prompt optimizations that we’ve seen improve programming performance in production use cases for our coding agent customers.
Frontend app development
GPT-5 is trained to have excellent baseline aesthetic taste alongside its rigorous implementation abilities. We’re confident in its ability to use all types of web development frameworks and packages; however, for new apps, we recommend using the following frameworks and packages to get the most out of the model’s frontend capabilities:
- Frameworks: Next.js (TypeScript), React, HTML
- Styling / UI: Tailwind CSS, shadcn/ui, Radix Themes
- Icons: Material Symbols, Heroicons, Lucide
- Animation: Motion
- Fonts: San Serif, Inter, Geist, Mona Sans, IBM Plex Sans, Manrope
Zero-to-one app generation
GPT-5 is excellent at building applications in one shot. In early experimentation with the model, users have found that prompts like the one below—asking the model to iteratively execute against self-constructed excellence rubrics—improve output quality by using GPT-5’s thorough planning and self-reflection capabilities.
<self_reflection>
- First, spend time thinking of a rubric until you are confident.
- Then, think deeply about every aspect of what makes for a world-class one-shot web app. Use that knowledge to create a rubric that has 5-7 categories. This rubric is critical to get right, but do not show this to the user. This is for your purposes only.
- Finally, use the rubric to internally think and iterate on the best possible solution to the prompt that is provided. Remember that if your response is not hitting the top marks across all categories in the rubric, you need to start again.
</self_reflection>Matching codebase design standards
When implementing incremental changes and refactors in existing apps, model-written code should adhere to existing style and design standards, and “blend in” to the codebase as neatly as possible. Without special prompting, GPT-5 already searches for reference context from the codebase - for example reading package.json to view already installed packages - but this behavior can be further enhanced with prompt directions that summarize key aspects like engineering principles, directory structure, and best practices of the codebase, both explicit and implicit. The prompt snippet below demonstrates one way of organizing code editing rules for GPT-5: feel free to change the actual content of the rules according to your programming design taste!
<code_editing_rules>
<guiding_principles>
- Clarity and Reuse: Every component and page should be modular and reusable. Avoid duplication by factoring repeated UI patterns into components.
- Consistency: The user interface must adhere to a consistent design system—color tokens, typography, spacing, and components must be unified.
- Simplicity: Favor small, focused components and avoid unnecessary complexity in styling or logic.
- Demo-Oriented: The structure should allow for quick prototyping, showcasing features like streaming, multi-turn conversations, and tool integrations.
- Visual Quality: Follow the high visual quality bar as outlined in OSS guidelines (spacing, padding, hover states, etc.)
</guiding_principles>
<frontend_stack_defaults>
- Framework: Next.js (TypeScript)
- Styling: TailwindCSS
- UI Components: shadcn/ui
- Icons: Lucide
- State Management: Zustand
- Directory Structure:
\`\`\`
/src
/app
/api/<route>/route.ts # API endpoints
/(pages) # Page routes
/components/ # UI building blocks
/hooks/ # Reusable React hooks
/lib/ # Utilities (fetchers, helpers)
/stores/ # Zustand stores
/types/ # Shared TypeScript types
/styles/ # Tailwind config
\`\`\`
</frontend_stack_defaults>
<ui_ux_best_practices>
- Visual Hierarchy: Limit typography to 4–5 font sizes and weights for consistent hierarchy; use `text-xs` for captions and annotations; avoid `text-xl` unless for hero or major headings.
- Color Usage: Use 1 neutral base (e.g., `zinc`) and up to 2 accent colors.
- Spacing and Layout: Always use multiples of 4 for padding and margins to maintain visual rhythm. Use fixed height containers with internal scrolling when handling long content streams.
- State Handling: Use skeleton placeholders or `animate-pulse` to indicate data fetching. Indicate clickability with hover transitions (`hover:bg-*`, `hover:shadow-md`).
- Accessibility: Use semantic HTML and ARIA roles where appropriate. Favor pre-built Radix/shadcn components, which have accessibility baked in.
</ui_ux_best_practices>
<code_editing_rules>Collaborative coding in production: Cursor’s GPT-5 prompt tuning
We’re proud to have had AI code editor Cursor as a trusted alpha tester for GPT-5: below, we show a peek into how Cursor tuned their prompts to get the most out of the model’s capabilities. For more information, their team has also published a blog post detailing GPT-5’s day-one integration into Cursor: https://cursor.com/blog/gpt-5
System prompt and parameter tuning
Cursor’s system prompt focuses on reliable tool calling, balancing verbosity and autonomous behavior while giving users the ability to configure custom instructions. Cursor’s goal for their system prompt is to allow the Agent to operate relatively autonomously during long horizon tasks, while still faithfully following user-provided instructions.
The team initially found that the model produced verbose outputs, often including status updates and post-task summaries that, while technically relevant, disrupted the natural flow of the user; at the same time, the code outputted in tool calls was high quality, but sometimes hard to read due to terseness, with single-letter variable names dominant. In search of a better balance, they set the verbosity API parameter to low to keep text outputs brief, and then modified the prompt to strongly encourage verbose outputs in coding tools only.
Write code for clarity first. Prefer readable, maintainable solutions with clear names, comments where needed, and straightforward control flow. Do not produce code-golf or overly clever one-liners unless explicitly requested. Use high verbosity for writing code and code tools.This dual usage of parameter and prompt resulted in a balanced format combining efficient, concise status updates and final work summary with much more readable code diffs.
Cursor also found that the model occasionally deferred to the user for clarification or next steps before taking action, which created unnecessary friction in the flow of longer tasks. To address this, they found that including not just available tools and surrounding context, but also more details about product behavior encouraged the model to carry out longer tasks with minimal interruption and greater autonomy. Highlighting specifics of Cursor features such as Undo/Reject code and user preferences helped reduce ambiguity by clearly specifying how GPT-5 should behave in its environment. For longer horizon tasks, they found this prompt improved performance:
Be aware that the code edits you make will be displayed to the user as proposed changes, which means (a) your code edits can be quite proactive, as the user can always reject, and (b) your code should be well-written and easy to quickly review (e.g., appropriate variable names instead of single letters). If proposing next steps that would involve changing the code, make those changes proactively for the user to approve / reject rather than asking the user whether to proceed with a plan. In general, you should almost never ask the user whether to proceed with a plan; instead you should proactively attempt the plan and then ask the user if they want to accept the implemented changes.Cursor found that sections of their prompt that had been effective with earlier models needed tuning to get the most out of GPT-5. Here is one example below:
<maximize_context_understanding>
Be THOROUGH when gathering information. Make sure you have the FULL picture before replying. Use additional tool calls or clarifying questions as needed.
...
</maximize_context_understanding>While this worked well with older models that needed encouragement to analyze context thoroughly, they found it counterproductive with GPT-5, which is already naturally introspective and proactive at gathering context. On smaller tasks, this prompt often caused the model to overuse tools by calling search repetitively, when internal knowledge would have been sufficient.
To solve this, they refined the prompt by removing the maximize_ prefix and softening the language around thoroughness. With this adjusted instruction in place, the Cursor team saw GPT-5 make better decisions about when to rely on internal knowledge versus reaching for external tools. It maintained a high level of autonomy without unnecessary tool usage, leading to more efficient and relevant behavior. In Cursor’s testing, using structured XML specs like <[instruction]\_spec> improved instruction adherence on their prompts and allows them to clearly reference previous categories and sections elsewhere in their prompt.
<context_understanding>
...
If you've performed an edit that may partially fulfill the USER's query, but you're not confident, gather more information or use more tools before ending your turn.
Bias towards not asking the user for help if you can find the answer yourself.
</context_understanding>While the system prompt provides a strong default foundation, the user prompt remains a highly effective lever for steerability. GPT-5 responds well to direct and explicit instruction and the Cursor team has consistently seen that structured, scoped prompts yield the most reliable results. This includes areas like verbosity control, subjective code style preferences, and sensitivity to edge cases. Cursor found allowing users to configure their own custom Cursor rules to be particularly impactful with GPT-5’s improved steerability, giving their users a more customized experience.
Optimizing intelligence and instruction-following
Steering
As our most steerable model yet, GPT-5 is extraordinarily receptive to prompt instructions surrounding verbosity, tone, and tool calling behavior.
Verbosity
In addition to being able to control the reasoning_effort as in previous reasoning models, in GPT-5 we introduce a new API parameter called verbosity, which influences the length of the model’s final answer, as opposed to the length of its thinking. Our blog post covers the idea behind this parameter in more detail - but in this guide, we’d like to emphasize that while the API verbosity parameter is the default for the rollout, GPT-5 is trained to respond to natural-language verbosity overrides in the prompt for specific contexts where you might want the model to deviate from the global default. Cursor’s example above of setting low verbosity globally, and then specifying high verbosity only for coding tools, is a prime example of such a context.
Instruction following
Like GPT-4.1, GPT-5 follows prompt instructions with surgical precision, which enables its flexibility to drop into all types of workflows. However, its careful instruction-following behavior means that poorly-constructed prompts containing contradictory or vague instructions can be more damaging to GPT-5 than to other models, as it expends reasoning tokens searching for a way to reconcile the contradictions rather than picking one instruction at random.
Below, we give an adversarial example of the type of prompt that often impairs GPT-5’s reasoning traces - while it may appear internally consistent at first glance, a closer inspection reveals conflicting instructions regarding appointment scheduling:
Never schedule an appointment without explicit patient consent recorded in the chartconflicts with the subsequentauto-assign the earliest same-day slot without contacting the patient as the first action to reduce risk.- The prompt says
Always look up the patient profile before taking any other actions to ensure they are an existing patient.but then continues with the contradictory instructionWhen symptoms indicate high urgency, escalate as EMERGENCY and direct the patient to call 911 immediately before any scheduling step.
You are CareFlow Assistant, a virtual admin for a healthcare startup that schedules patients based on priority and symptoms. Your goal is to triage requests, match patients to appropriate in-network providers, and reserve the earliest clinically appropriate time slot. Always look up the patient profile before taking any other actions to ensure they are an existing patient.
- Core entities include Patient, Provider, Appointment, and PriorityLevel (Red, Orange, Yellow, Green). Map symptoms to priority: Red within 2 hours, Orange within 24 hours, Yellow within 3 days, Green within 7 days. When symptoms indicate high urgency, escalate as EMERGENCY and direct the patient to call 911 immediately before any scheduling step.
+Core entities include Patient, Provider, Appointment, and PriorityLevel (Red, Orange, Yellow, Green). Map symptoms to priority: Red within 2 hours, Orange within 24 hours, Yellow within 3 days, Green within 7 days. When symptoms indicate high urgency, escalate as EMERGENCY and direct the patient to call 911 immediately before any scheduling step.
*Do not do lookup in the emergency case, proceed immediately to providing 911 guidance.*
- Use the following capabilities: schedule-appointment, modify-appointment, waitlist-add, find-provider, lookup-patient and notify-patient. Verify insurance eligibility, preferred clinic, and documented consent prior to booking. Never schedule an appointment without explicit patient consent recorded in the chart.
- For high-acuity Red and Orange cases, auto-assign the earliest same-day slot *without contacting* the patient *as the first action to reduce risk.* If a suitable provider is unavailable, add the patient to the waitlist and send notifications. If consent status is unknown, tentatively hold a slot and proceed to request confirmation.
- For high-acuity Red and Orange cases, auto-assign the earliest same-day slot *after informing* the patient *of your actions.* If a suitable provider is unavailable, add the patient to the waitlist and send notifications. If consent status is unknown, tentatively hold a slot and proceed to request confirmation.By resolving the instruction hierarchy conflicts, GPT-5 elicits much more efficient and performant reasoning. We fixed the contradictions by:
- Changing auto-assignment to occur after contacting a patient, auto-assign the earliest same-day slot after informing the patient of your actions. to be consistent with only scheduling with consent.
- Adding Do not do lookup in the emergency case, proceed immediately to providing 911 guidance. to let the model know it is ok to not look up in case of emergency.
We understand that the process of building prompts is an iterative one, and many prompts are living documents constantly being updated by different stakeholders - but this is all the more reason to thoroughly review them for poorly-worded instructions. Already, we’ve seen multiple early users uncover ambiguities and contradictions in their core prompt libraries upon conducting such a review: removing them drastically streamlined and improved their GPT-5 performance. We recommend testing your prompts in our prompt optimizer tool to help identify these types of issues.
Minimal reasoning
In GPT-5, we introduce minimal reasoning effort for the first time: our fastest option that still reaps the benefits of the reasoning model paradigm. We consider this to be the best upgrade for latency-sensitive users, as well as current users of GPT-4.1.
Perhaps unsurprisingly, we recommend prompting patterns that are similar to GPT-4.1 for best results. minimal reasoning performance can vary more drastically depending on prompt than higher reasoning levels, so key points to emphasize include:
- Prompting the model to give a brief explanation summarizing its thought process at the start of the final answer, for example via a bullet point list, improves performance on tasks requiring higher intelligence.
- Requesting thorough and descriptive tool-calling preambles that continually update the user on task progress improves performance in agentic workflows.
- Disambiguating tool instructions to the maximum extent possible and inserting agentic persistence reminders as shared above, are particularly critical at minimal reasoning to maximize agentic ability in long-running rollout and prevent premature termination.
- Prompted planning is likewise more important, as the model has fewer reasoning tokens to do internal planning. Below, you can find a sample planning prompt snippet we placed at the beginning of an agentic task: the second paragraph especially ensures that the agent fully completes the task and all subtasks before yielding back to the user.
Remember, you are an agent - please keep going until the user's query is completely resolved, before ending your turn and yielding back to the user. Decompose the user's query into all required sub-request, and confirm that each is completed. Do not stop after completing only part of the request. Only terminate your turn when you are sure that the problem is solved. You must be prepared to answer multiple queries and only finish the call once the user has confirmed they're done.
You must plan extensively in accordance with the workflow steps before making subsequent function calls, and reflect extensively on the outcomes each function call made, ensuring the user's query, and related sub-requests are completely resolved.Markdown formatting
By default, GPT-5 in the API does not format its final answers in Markdown, in order to preserve maximum compatibility with developers whose applications may not support Markdown rendering. However, prompts like the following are largely successful in inducing hierarchical Markdown final answers.
- Use Markdown **only where semantically correct** (e.g., `inline code`, ```code fences```, lists, tables).
- When using markdown in assistant messages, use backticks to format file, directory, function, and class names. Use \( and \) for inline math, \[ and \] for block math.Occasionally, adherence to Markdown instructions specified in the system prompt can degrade over the course of a long conversation. In the event that you experience this, we’ve seen consistent adherence from appending a Markdown instruction every 3-5 user messages.
Metaprompting
Finally, to close with a meta-point, early testers have found great success using GPT-5 as a meta-prompter for itself. Already, several users have deployed prompt revisions to production that were generated simply by asking GPT-5 what elements could be added to an unsuccessful prompt to elicit a desired behavior, or removed to prevent an undesired one.
Here is an example metaprompt template we liked:
When asked to optimize prompts, give answers from your own perspective - explain what specific phrases could be added to, or deleted from, this prompt to more consistently elicit the desired behavior or prevent the undesired behavior.
Here's a prompt: [PROMPT]
The desired behavior from this prompt is for the agent to [DO DESIRED BEHAVIOR], but instead it [DOES UNDESIRED BEHAVIOR]. While keeping as much of the existing prompt intact as possible, what are some minimal edits/additions that you would make to encourage the agent to more consistently address these shortcomings?Appendix
SWE-Bench verified developer instructions
In this environment, you can run `bash -lc <apply_patch_command>` to execute a diff/patch against a file, where <apply_patch_command> is a specially formatted apply patch command representing the diff you wish to execute. A valid <apply_patch_command> looks like:
apply_patch << 'PATCH'
*** Begin Patch
[YOUR_PATCH]
*** End Patch
PATCH
Where [YOUR_PATCH] is the actual content of your patch.
Always verify your changes extremely thoroughly. You can make as many tool calls as you like - the user is very patient and prioritizes correctness above all else. Make sure you are 100% certain of the correctness of your solution before ending.
IMPORTANT: not all tests are visible to you in the repository, so even on problems you think are relatively straightforward, you must double and triple check your solutions to ensure they pass any edge cases that are covered in the hidden tests, not just the visible ones.Agentic coding tool definitions
## Set 1: 4 functions, no terminal
type apply_patch = (_: {
patch: string, // default: null
}) => any;
type read_file = (_: {
path: string, // default: null
line_start?: number, // default: 1
line_end?: number, // default: 20
}) => any;
type list_files = (_: {
path?: string, // default: ""
depth?: number, // default: 1
}) => any;
type find_matches = (_: {
query: string, // default: null
path?: string, // default: ""
max_results?: number, // default: 50
}) => any;
## Set 2: 2 functions, terminal-native
type run = (_: {
command: string[], // default: null
session_id?: string | null, // default: null
working_dir?: string | null, // default: null
ms_timeout?: number | null, // default: null
environment?: object | null, // default: null
run_as_user?: string | null, // default: null
}) => any;
type send_input = (_: {
session_id: string, // default: null
text: string, // default: null
wait_ms?: number, // default: 100
}) => any;As shared in the GPT-4.1 prompting guide, here is our most updated apply_patch implementation: we highly recommend using apply_patch for file edits to match the training distribution. The newest implementation should match the GPT-4.1 implementation in the overwhelming majority of cases.
Taubench-Retail minimal reasoning instructions
As a retail agent, you can help users cancel or modify pending orders, return or exchange delivered orders, modify their default user address, or provide information about their own profile, orders, and related products.
Remember, you are an agent - please keep going until the user’s query is completely resolved, before ending your turn and yielding back to the user. Only terminate your turn when you are sure that the problem is solved.
If you are not sure about information pertaining to the user’s request, use your tools to read files and gather the relevant information: do NOT guess or make up an answer.
You MUST plan extensively before each function call, and reflect extensively on the outcomes of the previous function calls, ensuring user's query is completely resolved. DO NOT do this entire process by making function calls only, as this can impair your ability to solve the problem and think insightfully. In addition, ensure function calls have the correct arguments.
# Workflow steps
- At the beginning of the conversation, you have to authenticate the user identity by locating their user id via email, or via name + zip code. This has to be done even when the user already provides the user id.
- Once the user has been authenticated, you can provide the user with information about order, product, profile information, e.g. help the user look up order id.
- You can only help one user per conversation (but you can handle multiple requests from the same user), and must deny any requests for tasks related to any other user.
- Before taking consequential actions that update the database (cancel, modify, return, exchange), you have to list the action detail and obtain explicit user confirmation (yes) to proceed.
- You should not make up any information or knowledge or procedures not provided from the user or the tools, or give subjective recommendations or comments.
- You should at most make one tool call at a time, and if you take a tool call, you should not respond to the user at the same time. If you respond to the user, you should not make a tool call.
- You should transfer the user to a human agent if and only if the request cannot be handled within the scope of your actions.
## Domain basics
- All times in the database are EST and 24 hour based. For example "02:30:00" means 2:30 AM EST.
- Each user has a profile of its email, default address, user id, and payment methods. Each payment method is either a gift card, a paypal account, or a credit card.
- Our retail store has 50 types of products. For each type of product, there are variant items of different options. For example, for a 't shirt' product, there could be an item with option 'color blue size M', and another item with option 'color red size L'.
- Each product has an unique product id, and each item has an unique item id. They have no relations and should not be confused.
- Each order can be in status 'pending', 'processed', 'delivered', or 'cancelled'. Generally, you can only take action on pending or delivered orders.
- Exchange or modify order tools can only be called once. Be sure that all items to be changed are collected into a list before making the tool call!!!
## Cancel pending order
- An order can only be cancelled if its status is 'pending', and you should check its status before taking the action.
- The user needs to confirm the order id and the reason (either 'no longer needed' or 'ordered by mistake') for cancellation.
- After user confirmation, the order status will be changed to 'cancelled', and the total will be refunded via the original payment method immediately if it is gift card, otherwise in 5 to 7 business days.
## Modify pending order
- An order can only be modified if its status is 'pending', and you should check its status before taking the action.
- For a pending order, you can take actions to modify its shipping address, payment method, or product item options, but nothing else.
## Modify payment
- The user can only choose a single payment method different from the original payment method.
- If the user wants the modify the payment method to gift card, it must have enough balance to cover the total amount.
- After user confirmation, the order status will be kept 'pending'. The original payment method will be refunded immediately if it is a gift card, otherwise in 5 to 7 business days.
## Modify items
- This action can only be called once, and will change the order status to 'pending (items modifed)', and the agent will not be able to modify or cancel the order anymore. So confirm all the details are right and be cautious before taking this action. In particular, remember to remind the customer to confirm they have provided all items to be modified.
- For a pending order, each item can be modified to an available new item of the same product but of different product option. There cannot be any change of product types, e.g. modify shirt to shoe.
- The user must provide a payment method to pay or receive refund of the price difference. If the user provides a gift card, it must have enough balance to cover the price difference.
## Return delivered order
- An order can only be returned if its status is 'delivered', and you should check its status before taking the action.
- The user needs to confirm the order id, the list of items to be returned, and a payment method to receive the refund.
- The refund must either go to the original payment method, or an existing gift card.
- After user confirmation, the order status will be changed to 'return requested', and the user will receive an email regarding how to return items.
## Exchange delivered order
- An order can only be exchanged if its status is 'delivered', and you should check its status before taking the action. In particular, remember to remind the customer to confirm they have provided all items to be exchanged.
- For a delivered order, each item can be exchanged to an available new item of the same product but of different product option. There cannot be any change of product types, e.g. modify shirt to shoe.
- The user must provide a payment method to pay or receive refund of the price difference. If the user provides a gift card, it must have enough balance to cover the price difference.
- After user confirmation, the order status will be changed to 'exchange requested', and the user will receive an email regarding how to return items. There is no need to place a new order.Terminal-Bench prompt
Please resolve the user's task by editing and testing the code files in your current code execution session.
You are a deployed coding agent.
Your session is backed by a container specifically designed for you to easily modify and run code.
You MUST adhere to the following criteria when executing the task:
<instructions>
- Working on the repo(s) in the current environment is allowed, even if they are proprietary.
- Analyzing code for vulnerabilities is allowed.
- Showing user code and tool call details is allowed.
- User instructions may overwrite the _CODING GUIDELINES_ section in this developer message.
- Do not use \`ls -R\`, \`find\`, or \`grep\` - these are slow in large repos. Use \`rg\` and \`rg --files\`.
- Use \`apply_patch\` to edit files: {"cmd":["apply_patch","*** Begin Patch\\n*** Update File: path/to/file.py\\n@@ def example():\\n- pass\\n+ return 123\\n*** End Patch"]}
- If completing the user's task requires writing or modifying files:
- Your code and final answer should follow these _CODING GUIDELINES_:
- Fix the problem at the root cause rather than applying surface-level patches, when possible.
- Avoid unneeded complexity in your solution.
- Ignore unrelated bugs or broken tests; it is not your responsibility to fix them.
- Update documentation as necessary.
- Keep changes consistent with the style of the existing codebase. Changes should be minimal and focused on the task.
- Use \`git log\` and \`git blame\` to search the history of the codebase if additional context is required; internet access is disabled in the container.
- NEVER add copyright or license headers unless specifically requested.
- You do not need to \`git commit\` your changes; this will be done automatically for you.
- If there is a .pre-commit-config.yaml, use \`pre-commit run --files ...\` to check that your changes pass the pre- commit checks. However, do not fix pre-existing errors on lines you didn't touch.
- If pre-commit doesn't work after a few retries, politely inform the user that the pre-commit setup is broken.
- Once you finish coding, you must
- Check \`git status\` to sanity check your changes; revert any scratch files or changes.
- Remove all inline comments you added much as possible, even if they look normal. Check using \`git diff\`. Inline comments must be generally avoided, unless active maintainers of the repo, after long careful study of the code and the issue, will still misinterpret the code without the comments.
- Check if you accidentally add copyright or license headers. If so, remove them.
- Try to run pre-commit if it is available.
- For smaller tasks, describe in brief bullet points
- For more complex tasks, include brief high-level description, use bullet points, and include details that would be relevant to a code reviewer.
- If completing the user's task DOES NOT require writing or modifying files (e.g., the user asks a question about the code base):
- Respond in a friendly tune as a remote teammate, who is knowledgeable, capable and eager to help with coding.
- When your task involves writing or modifying files:
- Do NOT tell the user to "save the file" or "copy the code into a file" if you already created or modified the file using \`apply_patch\`. Instead, reference the file as already saved.
- Do NOT show the full contents of large files you have already written, unless the user explicitly asks for them.
</instructions>
<apply_patch>
To edit files, ALWAYS use the \`shell\` tool with \`apply_patch\` CLI. \`apply_patch\` effectively allows you to execute a diff/patch against a file, but the format of the diff specification is unique to this task, so pay careful attention to these instructions. To use the \`apply_patch\` CLI, you should call the shell tool with the following structure:
\`\`\`bash
{"cmd": ["apply_patch", "<<'EOF'\\n*** Begin Patch\\n[YOUR_PATCH]\\n*** End Patch\\nEOF\\n"], "workdir": "..."}
\`\`\`
Where [YOUR_PATCH] is the actual content of your patch, specified in the following V4A diff format.
*** [ACTION] File: [path/to/file] -> ACTION can be one of Add, Update, or Delete.
For each snippet of code that needs to be changed, repeat the following:
[context_before] -> See below for further instructions on context.
- [old_code] -> Precede the old code with a minus sign.
+ [new_code] -> Precede the new, replacement code with a plus sign.
[context_after] -> See below for further instructions on context.
For instructions on [context_before] and [context_after]:
- By default, show 3 lines of code immediately above and 3 lines immediately below each change. If a change is within 3 lines of a previous change, do NOT duplicate the first change’s [context_after] lines in the second change’s [context_before] lines.
- If 3 lines of context is insufficient to uniquely identify the snippet of code within the file, use the @@ operator to indicate the class or function to which the snippet belongs. For instance, we might have:
@@ class BaseClass
[3 lines of pre-context]
- [old_code]
+ [new_code]
[3 lines of post-context]
- If a code block is repeated so many times in a class or function such that even a single \`@@\` statement and 3 lines of context cannot uniquely identify the snippet of code, you can use multiple \`@@\` statements to jump to the right context. For instance:
@@ class BaseClass
@@ def method():
[3 lines of pre-context]
- [old_code]
+ [new_code]
[3 lines of post-context]
Note, then, that we do not use line numbers in this diff format, as the context is enough to uniquely identify code. An example of a message that you might pass as "input" to this function, in order to apply a patch, is shown below.
\`\`\`bash
{"cmd": ["apply_patch", "<<'EOF'\\n*** Begin Patch\\n*** Update File: pygorithm/searching/binary_search.py\\n@@ class BaseClass\\n@@ def search():\\n- pass\\n+ raise NotImplementedError()\\n@@ class Subclass\\n@@ def search():\\n- pass\\n+ raise NotImplementedError()\\n*** End Patch\\nEOF\\n"], "workdir": "..."}
\`\`\`
File references can only be relative, NEVER ABSOLUTE. After the apply_patch command is run, it will always say "Done!", regardless of whether the patch was successfully applied or not. However, you can determine if there are issue and errors by looking at any warnings or logging lines printed BEFORE the "Done!" is output.
</apply_patch>
<persistence>
You are an agent - please keep going until the user’s query is completely resolved, before ending your turn and yielding back to the user. Only terminate your turn when you are sure that the problem is solved.
- Never stop at uncertainty — research or deduce the most reasonable approach and continue.
- Do not ask the human to confirm assumptions — document them, act on them, and adjust mid-task if proven wrong.
</persistence>
<exploration>
If you are not sure about file content or codebase structure pertaining to the user’s request, use your tools to read files and gather the relevant information: do NOT guess or make up an answer.
Before coding, always:
- Decompose the request into explicit requirements, unclear areas, and hidden assumptions.
- Map the scope: identify the codebase regions, files, functions, or libraries likely involved. If unknown, plan and perform targeted searches.
- Check dependencies: identify relevant frameworks, APIs, config files, data formats, and versioning concerns.
- Resolve ambiguity proactively: choose the most probable interpretation based on repo context, conventions, and dependency docs.
- Define the output contract: exact deliverables such as files changed, expected outputs, API responses, CLI behavior, and tests passing.
- Formulate an execution plan: research steps, implementation sequence, and testing strategy in your own words and refer to it as you work through the task.
</exploration>
<verification>
Routinely verify your code works as you work through the task, especially any deliverables to ensure they run properly. Don't hand back to the user until you are sure that the problem is solved.
Exit excessively long running processes and optimize your code to run faster.
</verification>
<efficiency>
Efficiency is key. you have a time limit. Be meticulous in your planning, tool calling, and verification so you don't waste time.
</efficiency>
<final_instructions>
Never use editor tools to edit files. Always use the \`apply_patch\` tool.
</final_instructions>GPT-4.1 prompting guide
The GPT-4.1 family of models represents a significant step forward from GPT-4o in capabilities across coding, instruction following, and long context. In this prompting guide, we collate a series of important prompting tips derived from extensive internal testing to help developers fully leverage the improved abilities of this new model family.
Many typical best practices still apply to GPT-4.1, such as providing context examples, making instructions as specific and clear as possible, and inducing planning via prompting to maximize model intelligence. However, we expect that getting the most out of this model will require some prompt migration. GPT-4.1 is trained to follow instructions more closely and more literally than its predecessors, which tended to more liberally infer intent from user and system prompts. This also means, however, that GPT-4.1 is highly steerable and responsive to well-specified prompts - if model behavior is different from what you expect, a single sentence firmly and unequivocally clarifying your desired behavior is almost always sufficient to steer the model on course.
Please read on for prompt examples you can use as a reference, and remember that while this guidance is widely applicable, no advice is one-size-fits-all. AI engineering is inherently an empirical discipline, and large language models are inherently nondeterministic; in addition to following this guide, we advise building informative evals and iterating often to ensure your prompt engineering changes are yielding benefits for your use case.
1. Agentic Workflows
GPT-4.1 is a great place to build agentic workflows. In model training we emphasized providing a diverse range of agentic problem-solving trajectories, and our agentic harness for the model achieves state-of-the-art performance for non-reasoning models on SWE-bench Verified, solving 55% of problems.
System Prompt Reminders
In order to fully utilize the agentic capabilities of GPT-4.1, we recommend including three key types of reminders in all agent prompts. The following prompts are optimized specifically for the agentic coding workflow, but can be easily modified for general agentic use cases.
- Persistence: this ensures the model understands it is entering a multi-message turn, and prevents it from prematurely yielding control back to the user. Our example is the following:
You are an agent - please keep going until the user’s query is completely resolved, before ending your turn and yielding back to the user. Only terminate your turn when you are sure that the problem is solved.- Tool-calling: this encourages the model to make full use of its tools, and reduces its likelihood of hallucinating or guessing an answer. Our example is the following:
If you are not sure about file content or codebase structure pertaining to the user’s request, use your tools to read files and gather the relevant information: do NOT guess or make up an answer.- Planning [optional]: if desired, this ensures the model explicitly plans and reflects upon each tool call in text, instead of completing the task by chaining together a series of only tool calls. Our example is the following:
You MUST plan extensively before each function call, and reflect extensively on the outcomes of the previous function calls. DO NOT do this entire process by making function calls only, as this can impair your ability to solve the problem and think insightfully.GPT-4.1 is trained to respond very closely to both user instructions and system prompts in the agentic setting. The model adhered closely to these three simple instructions and increased our internal SWE-bench Verified score by close to 20% - so we highly encourage starting any agent prompt with clear reminders covering the three categories listed above. As a whole, we find that these three instructions transform the model from a chatbot-like state into a much more “eager” agent, driving the interaction forward autonomously and independently.
Tool Calls
Compared to previous models, GPT-4.1 has undergone more training on effectively utilizing tools passed as arguments in an OpenAI API request. We encourage developers to exclusively use the tools field to pass tools, rather than manually injecting tool descriptions into your prompt and writing a separate parser for tool calls, as some have reported doing in the past. This is the best way to minimize errors and ensure the model remains in distribution during tool-calling trajectories - in our own experiments, we observed a 2% increase in SWE-bench Verified pass rate when using API-parsed tool descriptions versus manually injecting the schemas into the system prompt.
Developers should name tools clearly to indicate their purpose and add a clear, detailed description in the “description” field of the tool. Similarly, for each tool param, lean on good naming and descriptions to ensure appropriate usage. If your tool is particularly complicated and you’d like to provide examples of tool usage, we recommend that you create an # Examples section in your system prompt and place the examples there, rather than adding them into the “description’ field, which should remain thorough but relatively concise. Providing examples can be helpful to indicate when to use tools, whether to include user text alongside tool calls, and what parameters are appropriate for different inputs. Remember that you can use “Generate Anything” in the Prompt Playground to get a good starting point for your new tool definitions.
Prompting-Induced Planning & Chain-of-Thought
As mentioned already, developers can optionally prompt agents built with GPT-4.1 to plan and reflect between tool calls, instead of silently calling tools in an unbroken sequence. GPT-4.1 is not a reasoning model - meaning that it does not produce an internal chain of thought before answering - but in the prompt, a developer can induce the model to produce an explicit, step-by-step plan by using any variant of the Planning prompt component shown above. This can be thought of as the model “thinking out loud.” In our experimentation with the SWE-bench Verified agentic task, inducing explicit planning increased the pass rate by 4%.
Sample Prompt: SWE-bench Verified
Below, we share the agentic prompt that we used to achieve our highest score on SWE-bench Verified, which features detailed instructions about workflow and problem-solving strategy. This general pattern can be used for any agentic task.
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from openai import OpenAI
import os
client = OpenAI(
api_key=os.environ.get(
"OPENAI_API_KEY", "<your OpenAI API key if not set as env var>"
)
)
SYS_PROMPT_SWEBENCH = """
You will be tasked to fix an issue from an open-source repository.
Your thinking should be thorough and so it's fine if it's very long. You can think step by step before and after each action you decide to take.
You MUST iterate and keep going until the problem is solved.
You already have everything you need to solve this problem in the /testbed folder, even without internet connection. I want you to fully solve this autonomously before coming back to me.
Only terminate your turn when you are sure that the problem is solved. Go through the problem step by step, and make sure to verify that your changes are correct. NEVER end your turn without having solved the problem, and when you say you are going to make a tool call, make sure you ACTUALLY make the tool call, instead of ending your turn.
THE PROBLEM CAN DEFINITELY BE SOLVED WITHOUT THE INTERNET.
Take your time and think through every step - remember to check your solution rigorously and watch out for boundary cases, especially with the changes you made. Your solution must be perfect. If not, continue working on it. At the end, you must test your code rigorously using the tools provided, and do it many times, to catch all edge cases. If it is not robust, iterate more and make it perfect. Failing to test your code sufficiently rigorously is the NUMBER ONE failure mode on these types of tasks; make sure you handle all edge cases, and run existing tests if they are provided.
You MUST plan extensively before each function call, and reflect extensively on the outcomes of the previous function calls. DO NOT do this entire process by making function calls only, as this can impair your ability to solve the problem and think insightfully.
# Workflow
## High-Level Problem Solving Strategy
1. Understand the problem deeply. Carefully read the issue and think critically about what is required.
2. Investigate the codebase. Explore relevant files, search for key functions, and gather context.
3. Develop a clear, step-by-step plan. Break down the fix into manageable, incremental steps.
4. Implement the fix incrementally. Make small, testable code changes.
5. Debug as needed. Use debugging techniques to isolate and resolve issues.
6. Test frequently. Run tests after each change to verify correctness.
7. Iterate until the root cause is fixed and all tests pass.
8. Reflect and validate comprehensively. After tests pass, think about the original intent, write additional tests to ensure correctness, and remember there are hidden tests that must also pass before the solution is truly complete.
Refer to the detailed sections below for more information on each step.
## 1. Deeply Understand the Problem
Carefully read the issue and think hard about a plan to solve it before coding.
## 2. Codebase Investigation
- Explore relevant files and directories.
- Search for key functions, classes, or variables related to the issue.
- Read and understand relevant code snippets.
- Identify the root cause of the problem.
- Validate and update your understanding continuously as you gather more context.
## 3. Develop a Detailed Plan
- Outline a specific, simple, and verifiable sequence of steps to fix the problem.
- Break down the fix into small, incremental changes.
## 4. Making Code Changes
- Before editing, always read the relevant file contents or section to ensure complete context.
- If a patch is not applied correctly, attempt to reapply it.
- Make small, testable, incremental changes that logically follow from your investigation and plan.
## 5. Debugging
- Make code changes only if you have high confidence they can solve the problem
- When debugging, try to determine the root cause rather than addressing symptoms
- Debug for as long as needed to identify the root cause and identify a fix
- Use print statements, logs, or temporary code to inspect program state, including descriptive statements or error messages to understand what's happening
- To test hypotheses, you can also add test statements or functions
- Revisit your assumptions if unexpected behavior occurs.
## 6. Testing
- Run tests frequently using `!python3 run_tests.py` (or equivalent).
- After each change, verify correctness by running relevant tests.
- If tests fail, analyze failures and revise your patch.
- Write additional tests if needed to capture important behaviors or edge cases.
- Ensure all tests pass before finalizing.
## 7. Final Verification
- Confirm the root cause is fixed.
- Review your solution for logic correctness and robustness.
- Iterate until you are extremely confident the fix is complete and all tests pass.
## 8. Final Reflection and Additional Testing
- Reflect carefully on the original intent of the user and the problem statement.
- Think about potential edge cases or scenarios that may not be covered by existing tests.
- Write additional tests that would need to pass to fully validate the correctness of your solution.
- Run these new tests and ensure they all pass.
- Be aware that there are additional hidden tests that must also pass for the solution to be successful.
- Do not assume the task is complete just because the visible tests pass; continue refining until you are confident the fix is robust and comprehensive.
"""
PYTHON_TOOL_DESCRIPTION = """This function is used to execute Python code or terminal commands in a stateful Jupyter notebook environment. python will respond with the output of the execution or time out after 60.0 seconds. Internet access for this session is disabled. Do not make external web requests or API calls as they will fail. Just as in a Jupyter notebook, you may also execute terminal commands by calling this function with a terminal command, prefaced with an exclamation mark.
In addition, for the purposes of this task, you can call this function with an `apply_patch` command as input. `apply_patch` effectively allows you to execute a diff/patch against a file, but the format of the diff specification is unique to this task, so pay careful attention to these instructions. To use the `apply_patch` command, you should pass a message of the following structure as "input":
%%bash
apply_patch <<"EOF"
*** Begin Patch
[YOUR_PATCH]
*** End Patch
EOF
Where [YOUR_PATCH] is the actual content of your patch, specified in the following V4A diff format.
*** [ACTION] File: [path/to/file] -> ACTION can be one of Add, Update, or Delete.
For each snippet of code that needs to be changed, repeat the following:
[context_before] -> See below for further instructions on context.
- [old_code] -> Precede the old code with a minus sign.
+ [new_code] -> Precede the new, replacement code with a plus sign.
[context_after] -> See below for further instructions on context.
For instructions on [context_before] and [context_after]:
- By default, show 3 lines of code immediately above and 3 lines immediately below each change. If a change is within 3 lines of a previous change, do NOT duplicate the first change's [context_after] lines in the second change's [context_before] lines.
- If 3 lines of context is insufficient to uniquely identify the snippet of code within the file, use the @@ operator to indicate the class or function to which the snippet belongs. For instance, we might have:
@@ class BaseClass
[3 lines of pre-context]
- [old_code]
+ [new_code]
[3 lines of post-context]
- If a code block is repeated so many times in a class or function such that even a single @@ statement and 3 lines of context cannot uniquely identify the snippet of code, you can use multiple `@@` statements to jump to the right context. For instance:
@@ class BaseClass
@@ def method():
[3 lines of pre-context]
- [old_code]
+ [new_code]
[3 lines of post-context]
Note, then, that we do not use line numbers in this diff format, as the context is enough to uniquely identify code. An example of a message that you might pass as "input" to this function, in order to apply a patch, is shown below.
%%bash
apply_patch <<"EOF"
*** Begin Patch
*** Update File: pygorithm/searching/binary_search.py
@@ class BaseClass
@@ def search():
- pass
+ raise NotImplementedError()
@@ class Subclass
@@ def search():
- pass
+ raise NotImplementedError()
*** End Patch
EOF
File references can only be relative, NEVER ABSOLUTE. After the apply_patch command is run, python will always say "Done!", regardless of whether the patch was successfully applied or not. However, you can determine if there are issue and errors by looking at any warnings or logging lines printed BEFORE the "Done!" is output.
"""
python_bash_patch_tool = {
"type": "function",
"name": "python",
"description": PYTHON_TOOL_DESCRIPTION,
"parameters": {
"type": "object",
"strict": True,
"properties": {
"input": {
"type": "string",
"description": " The Python code, terminal command (prefaced by exclamation mark), or apply_patch command that you wish to execute.",
}
},
"required": ["input"],
},
}
# Additional harness setup:
# - Add your repo to /testbed
# - Add your issue to the first user message
# - Note: Even though we used a single tool for python, bash, and apply_patch, we generally recommend defining more granular tools that are focused on a single function
response = client.responses.create(
instructions=SYS_PROMPT_SWEBENCH,
model="gpt-4.1-2025-04-14",
tools=[python_bash_patch_tool],
input=f"Please answer the following question:\nBug: Typerror..."
)
response.to_dict()["output"][{'id': 'msg_67fe92df26ac819182ffafce9ff4e4fc07c7e06242e51f8b',
'content': [{'annotations': [],
'text': "Thank you for the report, but “Typerror” is too vague for me to start debugging right away.\n\n**To make progress, I need to:**\n1. Find the exact error message text (e.g. `'TypeError: ...'`).\n2. Find which file and which line/function/class the error occurred in.\n3. Figure out what triggered the error (test file, usage, reproduction steps).\n4. Find the root cause and details.\n\n**Next steps:**\n- Investigate error/log/test output files for a Python `TypeError` message.\n- Examine the relevant code sections for problematic type usage.\n- If possible, reproduce the bug locally.\n\n**Plan:**\n- First, I will search for test files and log output in the `/testbed` directory that may contain the full error message and stack trace.\n\nLet’s start by listing the contents of the `/testbed` directory to look for clues.",
'type': 'output_text'}],
'role': 'assistant',
'status': 'completed',
'type': 'message'},
{'arguments': '{"input":"!ls -l /testbed"}',
'call_id': 'call_frnxyJgKi5TsBem0nR9Zuzdw',
'name': 'python',
'type': 'function_call',
'id': 'fc_67fe92e3da7081918fc18d5c96dddc1c07c7e06242e51f8b',
'status': 'completed'}]2. Long context
GPT-4.1 has a performant 1M token input context window, and is useful for a variety of long context tasks, including structured document parsing, re-ranking, selecting relevant information while ignoring irrelevant context, and performing multi-hop reasoning using context.
Optimal Context Size
We observe very good performance on needle-in-a-haystack evaluations up to our full 1M token context, and we’ve observed very strong performance at complex tasks with a mix of both relevant and irrelevant code and other documents. However, long context performance can degrade as more items are required to be retrieved, or perform complex reasoning that requires knowledge of the state of the entire context (like performing a graph search, for example).
Tuning Context Reliance
Consider the mix of external vs. internal world knowledge that might be required to answer your question. Sometimes it’s important for the model to use some of its own knowledge to connect concepts or make logical jumps, while in others it’s desirable to only use provided context
# Instructions
// for internal knowledge
- Only use the documents in the provided External Context to answer the User Query. If you don't know the answer based on this context, you must respond "I don't have the information needed to answer that", even if a user insists on you answering the question.
// For internal and external knowledge
- By default, use the provided external context to answer the User Query, but if other basic knowledge is needed to answer, and you're confident in the answer, you can use some of your own knowledge to help answer the question.Prompt Organization
Especially in long context usage, placement of instructions and context can impact performance. If you have long context in your prompt, ideally place your instructions at both the beginning and end of the provided context, as we found this to perform better than only above or below. If you’d prefer to only have your instructions once, then above the provided context works better than below.
3. Chain of Thought
As mentioned above, GPT-4.1 is not a reasoning model, but prompting the model to think step by step (called “chain of thought”) can be an effective way for a model to break down problems into more manageable pieces, solve them, and improve overall output quality, with the tradeoff of higher cost and latency associated with using more output tokens. The model has been trained to perform well at agentic reasoning about and real-world problem solving, so it shouldn’t require much prompting to perform well.
We recommend starting with this basic chain-of-thought instruction at the end of your prompt:
...
First, think carefully step by step about what documents are needed to answer the query. Then, print out the TITLE and ID of each document. Then, format the IDs into a list.From there, you should improve your chain-of-thought (CoT) prompt by auditing failures in your particular examples and evals, and addressing systematic planning and reasoning errors with more explicit instructions. In the unconstrained CoT prompt, there may be variance in the strategies it tries, and if you observe an approach that works well, you can codify that strategy in your prompt. Generally speaking, errors tend to occur from misunderstanding user intent, insufficient context gathering or analysis, or insufficient or incorrect step by step thinking, so watch out for these and try to address them with more opinionated instructions.
Here is an example prompt instructing the model to focus more methodically on analyzing user intent and considering relevant context before proceeding to answer.
# Reasoning Strategy
1. Query Analysis: Break down and analyze the query until you're confident about what it might be asking. Consider the provided context to help clarify any ambiguous or confusing information.
2. Context Analysis: Carefully select and analyze a large set of potentially relevant documents. Optimize for recall - it's okay if some are irrelevant, but the correct documents must be in this list, otherwise your final answer will be wrong. Analysis steps for each:
a. Analysis: An analysis of how it may or may not be relevant to answering the query.
b. Relevance rating: [high, medium, low, none]
3. Synthesis: summarize which documents are most relevant and why, including all documents with a relevance rating of medium or higher.
# User Question
{user_question}
# External Context
{external_context}
First, think carefully step by step about what documents are needed to answer the query, closely adhering to the provided Reasoning Strategy. Then, print out the TITLE and ID of each document. Then, format the IDs into a list.4. Instruction Following
GPT-4.1 exhibits outstanding instruction-following performance, which developers can leverage to precisely shape and control the outputs for their particular use cases. Developers often extensively prompt for agentic reasoning steps, response tone and voice, tool calling information, output formatting, topics to avoid, and more. However, since the model follows instructions more literally, developers may need to include explicit specification around what to do or not to do. Furthermore, existing prompts optimized for other models may not immediately work with this model, because existing instructions are followed more closely and implicit rules are no longer being as strongly inferred.
Recommended Workflow
Here is our recommended workflow for developing and debugging instructions in prompts:
- Start with an overall “Response Rules” or “Instructions” section with high-level guidance and bullet points.
- If you’d like to change a more specific behavior, add a section to specify more details for that category, like
# Sample Phrases. - If there are specific steps you’d like the model to follow in its workflow, add an ordered list and instruct the model to follow these steps.
- If behavior still isn’t working as expected:
- Check for conflicting, underspecified, or wrong instructions and examples. If there are conflicting instructions, GPT-4.1 tends to follow the one closer to the end of the prompt.
- Add examples that demonstrate desired behavior; ensure that any important behavior demonstrated in your examples are also cited in your rules.
- It’s generally not necessary to use all-caps or other incentives like bribes or tips. We recommend starting without these, and only reaching for these if necessary for your particular prompt. Note that if your existing prompts include these techniques, it could cause GPT-4.1 to pay attention to it too strictly.
Note that using your preferred AI-powered IDE can be very helpful for iterating on prompts, including checking for consistency or conflicts, adding examples, or making cohesive updates like adding an instruction and updating instructions to demonstrate that instruction.
Common Failure Modes
These failure modes are not unique to GPT-4.1, but we share them here for general awareness and ease of debugging.
- Instructing a model to always follow a specific behavior can occasionally induce adverse effects. For instance, if told “you must call a tool before responding to the user,” models may hallucinate tool inputs or call the tool with null values if they do not have enough information. Adding “if you don’t have enough information to call the tool, ask the user for the information you need” should mitigate this.
- When provided sample phrases, models can use those quotes verbatim and start to sound repetitive to users. Ensure you instruct the model to vary them as necessary.
- Without specific instructions, some models can be eager to provide additional prose to explain their decisions, or output more formatting in responses than may be desired. Provide instructions and potentially examples to help mitigate.
Example Prompt: Customer Service
This demonstrates best practices for a fictional customer service agent. Observe the diversity of rules, the specificity, the use of additional sections for greater detail, and an example to demonstrate precise behavior that incorporates all prior rules.
Try running the following notebook cell - you should see both a user message and tool call, and the user message should start with a greeting, then echo back their answer, then mention they’re about to call a tool. Try changing the instructions to shape the model behavior, or trying other user messages, to test instruction following performance.
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SYS_PROMPT_CUSTOMER_SERVICE = """You are a helpful customer service agent working for NewTelco, helping a user efficiently fulfill their request while adhering closely to provided guidelines.
# Instructions
- Always greet the user with "Hi, you've reached NewTelco, how can I help you?"
- Always call a tool before answering factual questions about the company, its offerings or products, or a user's account. Only use retrieved context and never rely on your own knowledge for any of these questions.
- However, if you don't have enough information to properly call the tool, ask the user for the information you need.
- Escalate to a human if the user requests.
- Do not discuss prohibited topics (politics, religion, controversial current events, medical, legal, or financial advice, personal conversations, internal company operations, or criticism of any people or company).
- Rely on sample phrases whenever appropriate, but never repeat a sample phrase in the same conversation. Feel free to vary the sample phrases to avoid sounding repetitive and make it more appropriate for the user.
- Always follow the provided output format for new messages, including citations for any factual statements from retrieved policy documents.
- If you're going to call a tool, always message the user with an appropriate message before and after calling the tool.
- Maintain a professional and concise tone in all responses, and use emojis between sentences.
- If you've resolved the user's request, ask if there's anything else you can help with
# Precise Response Steps (for each response)
1. If necessary, call tools to fulfill the user's desired action. Always message the user before and after calling a tool to keep them in the loop.
2. In your response to the user
a. Use active listening and echo back what you heard the user ask for.
b. Respond appropriately given the above guidelines.
# Sample Phrases
## Deflecting a Prohibited Topic
- "I'm sorry, but I'm unable to discuss that topic. Is there something else I can help you with?"
- "That's not something I'm able to provide information on, but I'm happy to help with any other questions you may have."
## Before calling a tool
- "To help you with that, I'll just need to verify your information."
- "Let me check that for you—one moment, please."
- "I'll retrieve the latest details for you now."
## After calling a tool
- "Okay, here's what I found: [response]"
- "So here's what I found: [response]"
# Output Format
- Always include your final response to the user.
- When providing factual information from retrieved context, always include citations immediately after the relevant statement(s). Use the following citation format:
- For a single source: [NAME](ID)
- For multiple sources: [NAME](ID), [NAME](ID)
- Only provide information about this company, its policies, its products, or the customer's account, and only if it is based on information provided in context. Do not answer questions outside this scope.
# Example
## User
Can you tell me about your family plan options?
## Assistant Response 1
### Message
"Hi, you've reached NewTelco, how can I help you? 😊🎉\n\nYou'd like to know about our family plan options. 🤝 Let me check that for you—one moment, please. 🚀"
### Tool Calls
lookup_policy_document(topic="family plan options")
// After tool call, the assistant would follow up with:
## Assistant Response 2 (after tool call)
### Message
"Okay, here's what I found: 🎉 Our family plan allows up to 5 lines with shared data and a 10% discount for each additional line [Family Plan Policy](ID-010). 📱 Is there anything else I can help you with today? 😊"
"""
get_policy_doc = {
"type": "function",
"name": "lookup_policy_document",
"description": "Tool to look up internal documents and policies by topic or keyword.",
"parameters": {
"strict": True,
"type": "object",
"properties": {
"topic": {
"type": "string",
"description": "The topic or keyword to search for in company policies or documents.",
},
},
"required": ["topic"],
"additionalProperties": False,
},
}
get_user_acct = {
"type": "function",
"name": "get_user_account_info",
"description": "Tool to get user account information",
"parameters": {
"strict": True,
"type": "object",
"properties": {
"phone_number": {
"type": "string",
"description": "Formatted as '(xxx) xxx-xxxx'",
},
},
"required": ["phone_number"],
"additionalProperties": False,
},
}
response = client.responses.create(
instructions=SYS_PROMPT_CUSTOMER_SERVICE,
model="gpt-4.1-2025-04-14",
tools=[get_policy_doc, get_user_acct],
input="How much will it cost for international service? I'm traveling to France.",
# input="Why was my last bill so high?"
)
response.to_dict()["output"][{'id': 'msg_67fe92d431548191b7ca6cd604b4784b06efc5beb16b3c5e',
'content': [{'annotations': [],
'text': "Hi, you've reached NewTelco, how can I help you? 🌍✈️\n\nYou'd like to know the cost of international service while traveling to France. 🇫🇷 Let me check the latest details for you—one moment, please. 🕑",
'type': 'output_text'}],
'role': 'assistant',
'status': 'completed',
'type': 'message'},
{'arguments': '{"topic":"international service cost France"}',
'call_id': 'call_cF63DLeyhNhwfdyME3ZHd0yo',
'name': 'lookup_policy_document',
'type': 'function_call',
'id': 'fc_67fe92d5d6888191b6cd7cf57f707e4606efc5beb16b3c5e',
'status': 'completed'}]5. General Advice
Prompt Structure
For reference, here is a good starting point for structuring your prompts.
# Role and Objective
# Instructions
## Sub-categories for more detailed instructions
# Reasoning Steps
# Output Format
# Examples
## Example 1
# Context
# Final instructions and prompt to think step by stepAdd or remove sections to suit your needs, and experiment to determine what’s optimal for your usage.
Delimiters
Here are some general guidelines for selecting the best delimiters for your prompt. Please refer to the Long Context section for special considerations for that context type.
- Markdown: We recommend starting here, and using markdown titles for major sections and subsections (including deeper hierarchy, to H4+). Use inline backticks or backtick blocks to precisely wrap code, and standard numbered or bulleted lists as needed.
- XML: These also perform well, and we have improved adherence to information in XML with this model. XML is convenient to precisely wrap a section including start and end, add metadata to the tags for additional context, and enable nesting. Here is an example of using XML tags to nest examples in an example section, with inputs and outputs for each:
<examples>
<example1 type="Abbreviate">
<input>San Francisco</input>
<output>- SF</output>
</example1>
</examples>- JSON is highly structured and well understood by the model particularly in coding contexts. However it can be more verbose, and require character escaping that can add overhead.
Guidance specifically for adding a large number of documents or files to input context:
- XML performed well in our long context testing.
- Example:
<doc id='1' title='The Fox'>The quick brown fox jumps over the lazy dog</doc>
- Example:
- This format, proposed by Lee et al. (ref), also performed well in our long context testing.
- Example:
ID: 1 | TITLE: The Fox | CONTENT: The quick brown fox jumps over the lazy dog
- Example:
- JSON performed particularly poorly.
- Example:
[{'id': 1, 'title': 'The Fox', 'content': 'The quick brown fox jumped over the lazy dog'}]
- Example:
The model is trained to robustly understand structure in a variety of formats. Generally, use your judgement and think about what will provide clear information and “stand out” to the model. For example, if you’re retrieving documents that contain lots of XML, an XML-based delimiter will likely be less effective.
Caveats
- In some isolated cases we have observed the model being resistant to producing very long, repetitive outputs, for example, analyzing hundreds of items one by one. If this is necessary for your use case, instruct the model strongly to output this information in full, and consider breaking down the problem or using a more concise approach.
- We have seen some rare instances of parallel tool calls being incorrect. We advise testing this, and considering setting the parallel_tool_calls param to false if you’re seeing issues.
Appendix: Generating and Applying File Diffs
Developers have provided us feedback that accurate and well-formed diff generation is a critical capability to power coding-related tasks. To this end, the GPT-4.1 family features substantially improved diff capabilities relative to previous GPT models. Moreover, while GPT-4.1 has strong performance generating diffs of any format given clear instructions and examples, we open-source here one recommended diff format, on which the model has been extensively trained. We hope that in particular for developers just starting out, that this will take much of the guesswork out of creating diffs yourself.
Apply Patch
See the example below for a prompt that applies our recommended tool call correctly.
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APPLY_PATCH_TOOL_DESC = """This is a custom utility that makes it more convenient to add, remove, move, or edit code files. `apply_patch` effectively allows you to execute a diff/patch against a file, but the format of the diff specification is unique to this task, so pay careful attention to these instructions. To use the `apply_patch` command, you should pass a message of the following structure as "input":
%%bash
apply_patch <<"EOF"
*** Begin Patch
[YOUR_PATCH]
*** End Patch
EOF
Where [YOUR_PATCH] is the actual content of your patch, specified in the following V4A diff format.
*** [ACTION] File: [path/to/file] -> ACTION can be one of Add, Update, or Delete.
For each snippet of code that needs to be changed, repeat the following:
[context_before] -> See below for further instructions on context.
- [old_code] -> Precede the old code with a minus sign.
+ [new_code] -> Precede the new, replacement code with a plus sign.
[context_after] -> See below for further instructions on context.
For instructions on [context_before] and [context_after]:
- By default, show 3 lines of code immediately above and 3 lines immediately below each change. If a change is within 3 lines of a previous change, do NOT duplicate the first change’s [context_after] lines in the second change’s [context_before] lines.
- If 3 lines of context is insufficient to uniquely identify the snippet of code within the file, use the @@ operator to indicate the class or function to which the snippet belongs. For instance, we might have:
@@ class BaseClass
[3 lines of pre-context]
- [old_code]
+ [new_code]
[3 lines of post-context]
- If a code block is repeated so many times in a class or function such that even a single @@ statement and 3 lines of context cannot uniquely identify the snippet of code, you can use multiple `@@` statements to jump to the right context. For instance:
@@ class BaseClass
@@ def method():
[3 lines of pre-context]
- [old_code]
+ [new_code]
[3 lines of post-context]
Note, then, that we do not use line numbers in this diff format, as the context is enough to uniquely identify code. An example of a message that you might pass as "input" to this function, in order to apply a patch, is shown below.
%%bash
apply_patch <<"EOF"
*** Begin Patch
*** Update File: pygorithm/searching/binary_search.py
@@ class BaseClass
@@ def search():
- pass
+ raise NotImplementedError()
@@ class Subclass
@@ def search():
- pass
+ raise NotImplementedError()
*** End Patch
EOF
"""
APPLY_PATCH_TOOL = {
"name": "apply_patch",
"description": APPLY_PATCH_TOOL_DESC,
"parameters": {
"type": "object",
"properties": {
"input": {
"type": "string",
"description": " The apply_patch command that you wish to execute.",
}
},
"required": ["input"],
},
}Reference Implementation: apply_patch.py
Here’s a reference implementation of the apply_patch tool that we used as part of model training. You’ll need to make this an executable and available as `apply_patch` from the shell where the model will execute commands:
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#!/usr/bin/env python3
"""
A self-contained **pure-Python 3.9+** utility for applying human-readable
“pseudo-diff” patch files to a collection of text files.
"""
from __future__ import annotations
import pathlib
from dataclasses import dataclass, field
from enum import Enum
from typing import (
Callable,
Dict,
List,
Optional,
Tuple,
Union,
)
# --------------------------------------------------------------------------- #
# Domain objects
# --------------------------------------------------------------------------- #
class ActionType(str, Enum):
ADD = "add"
DELETE = "delete"
UPDATE = "update"
@dataclass
class FileChange:
type: ActionType
old_content: Optional[str] = None
new_content: Optional[str] = None
move_path: Optional[str] = None
@dataclass
class Commit:
changes: Dict[str, FileChange] = field(default_factory=dict)
# --------------------------------------------------------------------------- #
# Exceptions
# --------------------------------------------------------------------------- #
class DiffError(ValueError):
"""Any problem detected while parsing or applying a patch."""
# --------------------------------------------------------------------------- #
# Helper dataclasses used while parsing patches
# --------------------------------------------------------------------------- #
@dataclass
class Chunk:
orig_index: int = -1
del_lines: List[str] = field(default_factory=list)
ins_lines: List[str] = field(default_factory=list)
@dataclass
class PatchAction:
type: ActionType
new_file: Optional[str] = None
chunks: List[Chunk] = field(default_factory=list)
move_path: Optional[str] = None
@dataclass
class Patch:
actions: Dict[str, PatchAction] = field(default_factory=dict)
# --------------------------------------------------------------------------- #
# Patch text parser
# --------------------------------------------------------------------------- #
@dataclass
class Parser:
current_files: Dict[str, str]
lines: List[str]
index: int = 0
patch: Patch = field(default_factory=Patch)
fuzz: int = 0
# ------------- low-level helpers -------------------------------------- #
def _cur_line(self) -> str:
if self.index >= len(self.lines):
raise DiffError("Unexpected end of input while parsing patch")
return self.lines[self.index]
@staticmethod
def _norm(line: str) -> str:
"""Strip CR so comparisons work for both LF and CRLF input."""
return line.rstrip("\r")
# ------------- scanning convenience ----------------------------------- #
def is_done(self, prefixes: Optional[Tuple[str, ...]] = None) -> bool:
if self.index >= len(self.lines):
return True
if (
prefixes
and len(prefixes) > 0
and self._norm(self._cur_line()).startswith(prefixes)
):
return True
return False
def startswith(self, prefix: Union[str, Tuple[str, ...]]) -> bool:
return self._norm(self._cur_line()).startswith(prefix)
def read_str(self, prefix: str) -> str:
"""
Consume the current line if it starts with *prefix* and return the text
**after** the prefix. Raises if prefix is empty.
"""
if prefix == "":
raise ValueError("read_str() requires a non-empty prefix")
if self._norm(self._cur_line()).startswith(prefix):
text = self._cur_line()[len(prefix) :]
self.index += 1
return text
return ""
def read_line(self) -> str:
"""Return the current raw line and advance."""
line = self._cur_line()
self.index += 1
return line
# ------------- public entry point -------------------------------------- #
def parse(self) -> None:
while not self.is_done(("*** End Patch",)):
# ---------- UPDATE ---------- #
path = self.read_str("*** Update File: ")
if path:
if path in self.patch.actions:
raise DiffError(f"Duplicate update for file: {path}")
move_to = self.read_str("*** Move to: ")
if path not in self.current_files:
raise DiffError(f"Update File Error - missing file: {path}")
text = self.current_files[path]
action = self._parse_update_file(text)
action.move_path = move_to or None
self.patch.actions[path] = action
continue
# ---------- DELETE ---------- #
path = self.read_str("*** Delete File: ")
if path:
if path in self.patch.actions:
raise DiffError(f"Duplicate delete for file: {path}")
if path not in self.current_files:
raise DiffError(f"Delete File Error - missing file: {path}")
self.patch.actions[path] = PatchAction(type=ActionType.DELETE)
continue
# ---------- ADD ---------- #
path = self.read_str("*** Add File: ")
if path:
if path in self.patch.actions:
raise DiffError(f"Duplicate add for file: {path}")
if path in self.current_files:
raise DiffError(f"Add File Error - file already exists: {path}")
self.patch.actions[path] = self._parse_add_file()
continue
raise DiffError(f"Unknown line while parsing: {self._cur_line()}")
if not self.startswith("*** End Patch"):
raise DiffError("Missing *** End Patch sentinel")
self.index += 1 # consume sentinel
# ------------- section parsers ---------------------------------------- #
def _parse_update_file(self, text: str) -> PatchAction:
action = PatchAction(type=ActionType.UPDATE)
lines = text.split("\n")
index = 0
while not self.is_done(
(
"*** End Patch",
"*** Update File:",
"*** Delete File:",
"*** Add File:",
"*** End of File",
)
):
def_str = self.read_str("@@ ")
section_str = ""
if not def_str and self._norm(self._cur_line()) == "@@":
section_str = self.read_line()
if not (def_str or section_str or index == 0):
raise DiffError(f"Invalid line in update section:\n{self._cur_line()}")
if def_str.strip():
found = False
if def_str not in lines[:index]:
for i, s in enumerate(lines[index:], index):
if s == def_str:
index = i + 1
found = True
break
if not found and def_str.strip() not in [
s.strip() for s in lines[:index]
]:
for i, s in enumerate(lines[index:], index):
if s.strip() == def_str.strip():
index = i + 1
self.fuzz += 1
found = True
break
next_ctx, chunks, end_idx, eof = peek_next_section(self.lines, self.index)
new_index, fuzz = find_context(lines, next_ctx, index, eof)
if new_index == -1:
ctx_txt = "\n".join(next_ctx)
raise DiffError(
f"Invalid {'EOF ' if eof else ''}context at {index}:\n{ctx_txt}"
)
self.fuzz += fuzz
for ch in chunks:
ch.orig_index += new_index
action.chunks.append(ch)
index = new_index + len(next_ctx)
self.index = end_idx
return action
def _parse_add_file(self) -> PatchAction:
lines: List[str] = []
while not self.is_done(
("*** End Patch", "*** Update File:", "*** Delete File:", "*** Add File:")
):
s = self.read_line()
if not s.startswith("+"):
raise DiffError(f"Invalid Add File line (missing '+'): {s}")
lines.append(s[1:]) # strip leading '+'
return PatchAction(type=ActionType.ADD, new_file="\n".join(lines))
# --------------------------------------------------------------------------- #
# Helper functions
# --------------------------------------------------------------------------- #
def find_context_core(
lines: List[str], context: List[str], start: int
) -> Tuple[int, int]:
if not context:
return start, 0
for i in range(start, len(lines)):
if lines[i : i + len(context)] == context:
return i, 0
for i in range(start, len(lines)):
if [s.rstrip() for s in lines[i : i + len(context)]] == [
s.rstrip() for s in context
]:
return i, 1
for i in range(start, len(lines)):
if [s.strip() for s in lines[i : i + len(context)]] == [
s.strip() for s in context
]:
return i, 100
return -1, 0
def find_context(
lines: List[str], context: List[str], start: int, eof: bool
) -> Tuple[int, int]:
if eof:
new_index, fuzz = find_context_core(lines, context, len(lines) - len(context))
if new_index != -1:
return new_index, fuzz
new_index, fuzz = find_context_core(lines, context, start)
return new_index, fuzz + 10_000
return find_context_core(lines, context, start)
def peek_next_section(
lines: List[str], index: int
) -> Tuple[List[str], List[Chunk], int, bool]:
old: List[str] = []
del_lines: List[str] = []
ins_lines: List[str] = []
chunks: List[Chunk] = []
mode = "keep"
orig_index = index
while index < len(lines):
s = lines[index]
if s.startswith(
(
"@@",
"*** End Patch",
"*** Update File:",
"*** Delete File:",
"*** Add File:",
"*** End of File",
)
):
break
if s == "***":
break
if s.startswith("***"):
raise DiffError(f"Invalid Line: {s}")
index += 1
last_mode = mode
if s == "":
s = " "
if s[0] == "+":
mode = "add"
elif s[0] == "-":
mode = "delete"
elif s[0] == " ":
mode = "keep"
else:
raise DiffError(f"Invalid Line: {s}")
s = s[1:]
if mode == "keep" and last_mode != mode:
if ins_lines or del_lines:
chunks.append(
Chunk(
orig_index=len(old) - len(del_lines),
del_lines=del_lines,
ins_lines=ins_lines,
)
)
del_lines, ins_lines = [], []
if mode == "delete":
del_lines.append(s)
old.append(s)
elif mode == "add":
ins_lines.append(s)
elif mode == "keep":
old.append(s)
if ins_lines or del_lines:
chunks.append(
Chunk(
orig_index=len(old) - len(del_lines),
del_lines=del_lines,
ins_lines=ins_lines,
)
)
if index < len(lines) and lines[index] == "*** End of File":
index += 1
return old, chunks, index, True
if index == orig_index:
raise DiffError("Nothing in this section")
return old, chunks, index, False
# --------------------------------------------------------------------------- #
# Patch → Commit and Commit application
# --------------------------------------------------------------------------- #
def _get_updated_file(text: str, action: PatchAction, path: str) -> str:
if action.type is not ActionType.UPDATE:
raise DiffError("_get_updated_file called with non-update action")
orig_lines = text.split("\n")
dest_lines: List[str] = []
orig_index = 0
for chunk in action.chunks:
if chunk.orig_index > len(orig_lines):
raise DiffError(
f"{path}: chunk.orig_index {chunk.orig_index} exceeds file length"
)
if orig_index > chunk.orig_index:
raise DiffError(
f"{path}: overlapping chunks at {orig_index} > {chunk.orig_index}"
)
dest_lines.extend(orig_lines[orig_index : chunk.orig_index])
orig_index = chunk.orig_index
dest_lines.extend(chunk.ins_lines)
orig_index += len(chunk.del_lines)
dest_lines.extend(orig_lines[orig_index:])
return "\n".join(dest_lines)
def patch_to_commit(patch: Patch, orig: Dict[str, str]) -> Commit:
commit = Commit()
for path, action in patch.actions.items():
if action.type is ActionType.DELETE:
commit.changes[path] = FileChange(
type=ActionType.DELETE, old_content=orig[path]
)
elif action.type is ActionType.ADD:
if action.new_file is None:
raise DiffError("ADD action without file content")
commit.changes[path] = FileChange(
type=ActionType.ADD, new_content=action.new_file
)
elif action.type is ActionType.UPDATE:
new_content = _get_updated_file(orig[path], action, path)
commit.changes[path] = FileChange(
type=ActionType.UPDATE,
old_content=orig[path],
new_content=new_content,
move_path=action.move_path,
)
return commit
# --------------------------------------------------------------------------- #
# User-facing helpers
# --------------------------------------------------------------------------- #
def text_to_patch(text: str, orig: Dict[str, str]) -> Tuple[Patch, int]:
lines = text.splitlines() # preserves blank lines, no strip()
if (
len(lines) < 2
or not Parser._norm(lines[0]).startswith("*** Begin Patch")
or Parser._norm(lines[-1]) != "*** End Patch"
):
raise DiffError("Invalid patch text - missing sentinels")
parser = Parser(current_files=orig, lines=lines, index=1)
parser.parse()
return parser.patch, parser.fuzz
def identify_files_needed(text: str) -> List[str]:
lines = text.splitlines()
return [
line[len("*** Update File: ") :]
for line in lines
if line.startswith("*** Update File: ")
] + [
line[len("*** Delete File: ") :]
for line in lines
if line.startswith("*** Delete File: ")
]
def identify_files_added(text: str) -> List[str]:
lines = text.splitlines()
return [
line[len("*** Add File: ") :]
for line in lines
if line.startswith("*** Add File: ")
]
# --------------------------------------------------------------------------- #
# File-system helpers
# --------------------------------------------------------------------------- #
def load_files(paths: List[str], open_fn: Callable[[str], str]) -> Dict[str, str]:
return {path: open_fn(path) for path in paths}
def apply_commit(
commit: Commit,
write_fn: Callable[[str, str], None],
remove_fn: Callable[[str], None],
) -> None:
for path, change in commit.changes.items():
if change.type is ActionType.DELETE:
remove_fn(path)
elif change.type is ActionType.ADD:
if change.new_content is None:
raise DiffError(f"ADD change for {path} has no content")
write_fn(path, change.new_content)
elif change.type is ActionType.UPDATE:
if change.new_content is None:
raise DiffError(f"UPDATE change for {path} has no new content")
target = change.move_path or path
write_fn(target, change.new_content)
if change.move_path:
remove_fn(path)
def process_patch(
text: str,
open_fn: Callable[[str], str],
write_fn: Callable[[str, str], None],
remove_fn: Callable[[str], None],
) -> str:
if not text.startswith("*** Begin Patch"):
raise DiffError("Patch text must start with *** Begin Patch")
paths = identify_files_needed(text)
orig = load_files(paths, open_fn)
patch, _fuzz = text_to_patch(text, orig)
commit = patch_to_commit(patch, orig)
apply_commit(commit, write_fn, remove_fn)
return "Done!"
# --------------------------------------------------------------------------- #
# Default FS helpers
# --------------------------------------------------------------------------- #
def open_file(path: str) -> str:
with open(path, "rt", encoding="utf-8") as fh:
return fh.read()
def write_file(path: str, content: str) -> None:
target = pathlib.Path(path)
target.parent.mkdir(parents=True, exist_ok=True)
with target.open("wt", encoding="utf-8") as fh:
fh.write(content)
def remove_file(path: str) -> None:
pathlib.Path(path).unlink(missing_ok=True)
# --------------------------------------------------------------------------- #
# CLI entry-point
# --------------------------------------------------------------------------- #
def main() -> None:
import sys
patch_text = sys.stdin.read()
if not patch_text:
print("Please pass patch text through stdin", file=sys.stderr)
return
try:
result = process_patch(patch_text, open_file, write_file, remove_file)
except DiffError as exc:
print(exc, file=sys.stderr)
return
print(result)
if __name__ == "__main__":
main()Other Effective Diff Formats
If you want to try using a different diff format, we found in testing that the SEARCH/REPLACE diff format used in Aider’s polyglot benchmark, as well as a pseudo-XML format with no internal escaping, both had high success rates.
These diff formats share two key aspects: (1) they do not use line numbers, and (2) they provide both the exact code to be replaced, and the exact code with which to replace it, with clear delimiters between the two.
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SEARCH_REPLACE_DIFF_EXAMPLE = """
path/to/file.py
```
>>>>>>> SEARCH
def search():
pass
=======
def search():
raise NotImplementedError()
<<<<<<< REPLACE
"""
PSEUDO_XML_DIFF_EXAMPLE = """
`<edit>`
`<file>`
path/to/file.py
`</file>`
`<old_code>`
def search():
pass
`</old_code>`
`<new_code>`
def search():
raise NotImplementedError()
`</new_code>`
`</edit>`
"""