Hello,
I am trying to connect Square’s hosted MCP server to Google Gemini Spark using:
https://mcp.squareup.com/mcp
Client: Google Gemini Spark custom connected app
OAuth redirect URI:
https://oauth-redirect.googleusercontent.com/r/user_bound_custom-mcp-107303354335300565420-mcp_squareup_com
I created a Square production developer application, configured the redirect URI, and entered the Production Application ID and Application Secret into Gemini.
The OAuth flow reaches Google’s MCP connection screen, but after continuing it returns:
Internal Server Error
Can Google Gemini Spark please be added to the Square MCP client allowlist, or can you confirm whether any additional OAuth configuration is required?
Thank you.