Changelog

New features, fixes, and API updates, shipped continuously.
January 6, 2026

GPT-5.2 is now supported

Added GPT-5.2 support for agents.

EndpointTitle
POST /assistantsCreate an agent
PUT /assistants/:model_idUpdate an agent
$"agent": {
>   "llm": "gpt-5.2"
> }

New parameter: message_before_action_starts for custom actions

Custom actions now support an optional message_before_action_starts parameter that allows you to specify a message the agent will speak before the action is triggered.

What is it? This optional string parameter lets you set a custom message that the agent will say before executing a custom action, providing better user experience and context during action execution.

EndpointTitle
POST /actionsCreate an action
PUT /actions/{action_id}Update an action
$"CUSTOM_ACTION": {
>   "http_mode": "GET",
>   "url": "https://example.com/api",
>   "message_before_action_starts": "Let me check that for you"
> }