call_id: string

An identifier used to map this custom tool call to a tool call output.

input: string

The input for the custom tool call generated by the model.

name: string

The name of the custom tool being called.

type: "custom_tool_call"

The type of the custom tool call. Always custom_tool_call.

id?: string

The unique ID of the custom tool call in the OpenAI platform.

async?: boolean

Whether the custom tool call runs asynchronously.

caller?: Direct { type } | Program { caller_id, type } | null

The execution context that produced this tool call.

One of the following:

Direct { type }

type: "direct"

Program { caller_id, type }

caller_id: string

The call ID of the program item that produced this tool call.

type: "program"

namespace?: string

The namespace of the custom tool being called.