Vercel MCP OAuth fails from Cursor cloud-agents dashboard

Vercel MCP OAuth fails from Cursor cloud-agents dashboard: "The app redirect URL is invalid" Attempting to authenticate the Vercel MCP (https://mcp.vercel.com) for Cursor cloud agents from cursor.com/dashboard/integrations fails on Vercel's authorize page with "App configuration error — The app redirect URL is invalid", before the callback returns to Cursor. Authorize URL shows client_id=cl_eD921KDq5R4BhfW5pRKJ6KHgY7d0JycM, code_challenge_method=S256. Reproduced 2026-07-20 in a fresh incognito session, two different accounts, and after removing/re-adding the MCP server. Cloud agents/automations use the https://www.cursor.com/agents/mcp/oauth/callback redirect — please confirm it's registered on the Vercel OAuth client used by the MCP integration (same class of issue as forum thread 159005 and the Linear case in 158845, where the fix was provider-side registration of Cursor's callback).

Confirming the same issue on 2026-08-15 from a Miami Web AI Pro account.

Cursor Cloud / Agents / Automations sends https://www.cursor.com/agents/mcp/oauth/callback
Vercel OAuth client is cl_eD921KDq5R4BhfW5pRKJ6KHgY7d0JycM
Vercel stops before consent with “App configuration error — The app redirect URL is invalid”
The official Vercel MCP remains Offline/Needs Authentication in Cursor Cloud
Cursor Desktop 3.16.17 connects to the same official MCP locally, so the failure is isolated to the Cloud callback path

Reproduced after fresh Cursor and Vercel sign-ins, browser retry, Cursor restart, and disabling/re-enabling the MCP. An existing desktop OAuth grant does not authenticate Cloud Agents. This blocks scheduled Automations that depend on Vercel MCP.

I also tried Vercel Support, but selecting AI → Vercel MCP says the Beta is supported exclusively through this Community, so no private case can be submitted.

Please route this to the Vercel MCP / OAuth integration team to register the Cursor Cloud callback above, or coordinate the fix with Cursor. No token or full OAuth state/code-challenge URL is included.