Understand the developer API

The developer API lets your server-side application request supported ChatterMate capabilities using an API key. It is separate from signing in through the browser.

The existing in-product API documentation is the current public entry point. Use it to check the current request format and available capabilities.

Core API endpoints

Method	Path	Purpose
GET	/api/chat/models	Discover text-chat model choices
POST	/api/chat/estimate	Estimate a proposed chat request
POST	/api/chat/stream	Stream a response

Send the key in the X-API-Key header. The reviewed key format begins with cm_live_. Model discovery and estimates reflect account access; use an allowed returned model identifier rather than guessing one.

Use the API base URL shown in the public API documentation. Keep your API key on your server.

Continue with API keys, First request, and Streaming and errors.