MCP not calling the correct Project name

[Pollinate_IQ]

Where does the bug appear (feature/product)?

Cursor IDE

Describe the Bug

Hi Cursor, Team I have been noticing this issue with Cursor IDE I will ask it to check to look up my Supabase backend and it will always most the of time use a project id that is made up, this can be problem especially when you use plan mode the agent needs to a full analysis and getting the incorrect ProjectID this causes the Context to be filled up because the agent has to fall back to search through the files in the code

Steps to Reproduce

Just set Supabase a MCP start create project ask the model to look into the MCP server do it many times you notice then you see the bug

Operating System

Windows 10/11

Current Cursor Version (Menu → About Cursor → Copy)

Version: 2.3.15 (user setup)
VSCode Version: 1.105.1
Date: 2025-12-30T20:30:37.151Z
Electron: 37.7.0
Chromium: 138.0.7204.251
Node.js: 22.20.0
V8: 13.8.258.32-electron.0
OS: Windows_NT x64 10.0.26220

For AI issues: which model did you use?

All Claude models, Composer, GPT, and Gemini, even API GLM 4.7

Does this stop you from using Cursor

No - Cursor works, but with this issue

[sanjeed5 (Sanjeed)]

Hi @Pollinate_IQ, thanks for the detailed report.

This sounds like AI model hallucination rather than an MCP bug - the models are guessing project IDs instead of retrieving them from Supabase. The best fix is to add a cursor rule (.cursor/rules file) that includes your actual project ID:

My Supabase project ID is: abc123xyz
Always use this project ID for all Supabase operations. Never guess or assume a different project ID.

See the Rules documentation for setup details. This way the model has the correct ID directly in context and won’t hallucinate.

Alternatively, you can be more explicit in prompts - e.g., “First, use the MCP server to get my Supabase project ID, then…”

Let me know if that helps!