CustomToolCallItem - Python SDK

CustomToolCallItem method reference

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A call to a custom (freeform-grammar) tool created by the model — distinct from function_call. Used for tools like Codex CLI’s apply_patch whose payload is opaque text rather than JSON arguments.

Fields

Field	Type	Required	Description
call_id	str	:heavy_check_mark:	N/A
id	Optional[str]	:heavy_minus_sign:	N/A
input	str	:heavy_check_mark:	N/A
name	str	:heavy_check_mark:	N/A
namespace	Optional[str]	:heavy_minus_sign:	Namespace qualifier for tools registered as part of a namespace tool group (e.g. an MCP server)
type	components.CustomToolCallItemType	:heavy_check_mark:	N/A