Materialize an API chat

Surface an API-created chat into chat history and return a shareable deep link.

Chats created through POST /chat/completions stay out of chat history (both the GC AI web app and chat search) until you materialize them. Use the chat_id from a completed completion response. The endpoint is idempotent. Calling it again on an already-materialized chat returns the same link without side effects.

Pass project_id to file the chat into a project at the same time, so it is browsable under GET /projects/{id}/chats. This requires write access to the project and files a chat that is already materialized.

Authorization: User-scoped keys can only materialize chats they created. Organization-scoped keys can only materialize chats created by other organization-scoped keys.

Who can use the chat afterwards: An organization-scoped key shares the chat with the whole organization, and every member can continue it in the web app. A user-scoped key keeps the chat owned by that user, so teammates reach it only through the normal sharing rules.

See Chat Visibility for how this works.