Stitch MCP not working with API key

Stitch
1

Tried to setup MCP server on antigravity and gemini cli both failed:
antigravity : error bad request. connection closed
gemini cli :
MCP tool ‘list_projects’ reported tool error for function call: {“name”:“list_projects”,“args”:{}} │
│ with response: [{“functionResponse”:{“name”:“list_projects”,“response”:{“error”:{“message”:"Streamable │
│ HTTP error: Error POSTing to endpoint: │
│ {“id”:2,“jsonrpc”:“2.0”,“result”:{“content”:[{“text”:"API keys are not supported by this │
│ API. Expected OAuth2 access token or other authentication credentials that assert a principal. See │
│ https://cloud.google.com/docs/authentication\“,\“type\”:\“text\”}],\“isError\”:true}}”,“isError”:true} │
│ }}}]

2

I’m facing the same problem. I’m using Cursor.

3

Facing the same problem, can’t use with antigravity.

4

I have just encountered this issue