- ChatGPT: custom OAuth MCP connections require Developer mode and account/workspace permission. A personal key alone cannot add HTTP tools to a chat.
- Cursor: Settings → MCP → Add Server with the endpoint above, or paste the setup prompt and Cursor configures itself.
- Grok / Grok Build / Grok Bot: Bring-Your-Own-MCP where supported, otherwise the REST API with a bearer key. Grok Bot takes the key in its task instructions.
Whatever the client, it's the same account, credits, and rules: exploring is free, spending is explicit.