author: string

The sending agent identity.

content: Array<BetaResponseInputTextContent { text, type, prompt_cache_breakpoint } | BetaResponseInputImageContent { type, detail, file_id, 2 more } | EncryptedContent { encrypted_content, type } >

Plaintext, image, or encrypted content sent between agents.

One of the following:
BetaResponseInputTextContent { text, type, prompt_cache_breakpoint }

A text input to the model.

text: string

The text input to the model.

maxLength10485760
type: "input_text"

The type of the input item. Always input_text.

prompt_cache_breakpoint?: PromptCacheBreakpoint | null

Marks the exact end of a reusable prompt prefix. The breakpoint inherits its TTL from the request’s prompt_cache_options.ttl; the boundary is not rounded to a token block.

mode: "explicit"

The breakpoint mode. Always explicit.

BetaResponseInputImageContent { type, detail, file_id, 2 more }

An image input to the model. Learn about image inputs

type: "input_image"

The type of the input item. Always input_image.

detail?: BetaImageDetail | null

The detail level of the image to be sent to the model. One of high, low, auto, or original. Defaults to auto.

One of the following:
"low"
"high"
"auto"
"original"
file_id?: string | null

The ID of the file to be sent to the model.

image_url?: string | null

The URL of the image to be sent to the model. A fully qualified URL or base64 encoded image in a data URL.

maxLength20971520
formaturi
prompt_cache_breakpoint?: PromptCacheBreakpoint | null

Marks the exact end of a reusable prompt prefix. The breakpoint inherits its TTL from the request’s prompt_cache_options.ttl; the boundary is not rounded to a token block.

mode: "explicit"

The breakpoint mode. Always explicit.

EncryptedContent { encrypted_content, type }

Opaque encrypted content that Responses API decrypts inside trusted model execution.

encrypted_content: string

Opaque encrypted content.

maxLength10485760
type: "encrypted_content"

The type of the input item. Always encrypted_content.

recipient: string

The destination agent identity.

type: "agent_message"

The item type. Always agent_message.

id?: string | null

The unique ID of this agent message item.

agent?: Agent | null

The agent that produced this item.

agent_name: string

The canonical name of the agent that produced this item.