Attach an already-uploaded file to a project. The file remains in its current folder; this only records the project link.
Requires a user-scoped API key (u:gcai_...) with write access to the project and read access to the file.
Documentation Index
Fetch the complete documentation index at: https://docs.gc.ai/llms.txt
Use this file to discover all available pages before exploring further.
API key for authentication. Format: gcai_xxxxxxxxx
Create API keys in the GC AI app under Settings → API.
The project ID
ID of an already-uploaded file to attach to the project
File attached (idempotent, repeat calls are no-ops)