Non-interactive mode lets you run Codex from scripts (for example, continuous integration (CI) jobs) without opening the interactive TUI.
You invoke it with codex exec.
For flag-level details, see codex exec.
When to use codex exec
Use codex exec when you want Codex to:
- Run as part of a pipeline (CI, pre-merge checks, scheduled jobs).
- Produce output you can pipe into other tools (for example, to generate release notes or summaries).
- Run with explicit, pre-set sandbox and approval settings.
Basic usage
Pass a task prompt as a single argument:
codex exec "summarize the repository structure and list the top 5 risky areas"
While codex exec runs, Codex streams progress to stderr and prints only the final agent message to stdout. This makes it straightforward to redirect or pipe the final result:
codex exec "generate release notes for the last 10 commits" | tee release-notes.md
Permissions and safety
By default, codex exec runs in a read-only sandbox. In automation, set the least permissions needed for the workflow:
- Allow edits:
codex exec --full-auto "<task>" - Allow broader access:
codex exec --sandbox danger-full-access "<task>"
Use danger-full-access only in a controlled environment (for example, an isolated CI runner or container).
Make output machine-readable
To consume Codex output in scripts, use JSON Lines output:
codex exec --json "summarize the repo structure" | jq
When you enable --json, stdout becomes a JSON Lines (JSONL) stream so you can capture every event Codex emits while it’s running. Event types include thread.started, turn.started, turn.completed, turn.failed, item.*, and error.
Item types include agent messages, reasoning, command executions, file changes, MCP tool calls, web searches, and plan updates.
Sample JSON stream (each line is a JSON object):
{"type":"thread.started","thread_id":"0199a213-81c0-7800-8aa1-bbab2a035a53"}
{"type":"turn.started"}
{"type":"item.started","item":{"id":"item_1","type":"command_execution","command":"bash -lc ls","status":"in_progress"}}
{"type":"item.completed","item":{"id":"item_3","type":"agent_message","text":"Repo contains docs, sdk, and examples directories."}}
{"type":"turn.completed","usage":{"input_tokens":24763,"cached_input_tokens":24448,"output_tokens":122}}
If you only need the final message, write it to a file with -o <path>/--output-last-message <path>. This writes the final message to the file and still prints it to stdout (see codex exec for details).
Create structured outputs with a schema
If you need structured data for downstream steps, use --output-schema to request a final response that conforms to a JSON Schema.
This is useful for automated workflows that need stable fields (for example, job summaries, risk reports, or release metadata).
schema.json
{
"type": "object",
"properties": {
"project_name": { "type": "string" },
"programming_languages": {
"type": "array",
"items": { "type": "string" }
}
},
"required": ["project_name", "programming_languages"],
"additionalProperties": false
}
Run Codex with the schema and write the final JSON response to disk:
codex exec "Extract project metadata" \
--output-schema ./schema.json \
-o ./project-metadata.json
Example final output (stdout):
{
"project_name": "Codex CLI",
"programming_languages": ["Rust", "TypeScript", "Shell"]
}
Authenticate in CI
codex exec reuses saved CLI authentication by default. In CI, it’s common to provide credentials explicitly:
- Set
CODEX_API_KEYas a secret environment variable for the job. - Keep prompts and tool output in mind: they can include sensitive code or data.
To use a different API key for a single run, set CODEX_API_KEY inline:
CODEX_API_KEY=<api-key> codex exec --json "triage open bug reports"
CODEX_API_KEY is only supported in codex exec.
Resume a non-interactive session
If you need to continue a previous run (for example, a two-stage pipeline), use the resume subcommand:
codex exec "review the change for race conditions"
codex exec resume --last "fix the race conditions you found"
You can also target a specific session ID with codex exec resume <SESSION_ID>.
Git repository required
Codex requires commands to run inside a Git repository to prevent destructive changes. Override this check with codex exec --skip-git-repo-check if you’re sure the environment is safe.
Common automation patterns
Example: Autofix CI failures in GitHub Actions
You can use codex exec to automatically propose fixes when a CI workflow fails. The typical pattern is:
- Trigger a follow-up workflow when your main CI workflow completes with an error.
- Check out the failing commit SHA.
- Install dependencies and run Codex with a narrow prompt and minimal permissions.
- Re-run the test command.
- Open a pull request with the resulting patch.
Minimal workflow using the Codex CLI
The example below shows the core steps. Adjust the install and test commands to match your stack.
name: Codex auto-fix on CI failure
on:
workflow_run:
workflows: ["CI"]
types: [completed]
permissions:
contents: write
pull-requests: write
jobs:
auto-fix:
if: ${{ github.event.workflow_run.conclusion == 'failure' }}
runs-on: ubuntu-latest
env:
OPENAI_API_KEY: ${{ secrets.OPENAI_API_KEY }}
FAILED_HEAD_SHA: ${{ github.event.workflow_run.head_sha }}
FAILED_HEAD_BRANCH: ${{ github.event.workflow_run.head_branch }}
steps:
- uses: actions/checkout@v4
with:
ref: ${{ env.FAILED_HEAD_SHA }}
fetch-depth: 0
- uses: actions/setup-node@v4
with:
node-version: "20"
- name: Install dependencies
run: |
if [ -f package-lock.json ]; then npm ci; else npm i; fi
- name: Install Codex
run: npm i -g @openai/codex
- name: Authenticate Codex
run: codex login --api-key "$OPENAI_API_KEY"
- name: Run Codex
run: |
codex exec --full-auto --sandbox workspace-write \
"Read the repository, run the test suite, identify the minimal change needed to make all tests pass, implement only that change, and stop. Do not refactor unrelated files."
- name: Verify tests
run: npm test --silent
- name: Create pull request
if: success()
uses: peter-evans/create-pull-request@v6
with:
branch: codex/auto-fix-${{ github.event.workflow_run.run_id }}
base: ${{ env.FAILED_HEAD_BRANCH }}
title: "Auto-fix failing CI via Codex"
Alternative: Use the Codex GitHub Action
If you want to avoid installing the CLI yourself, you can run codex exec through the Codex GitHub Action and pass the prompt as an input.