Cursor·Fixpromptingintermediate

Cursor Using APIs That Don't Exist

Quick Answer

The AI generates code based on patterns from training data, not your actual codebase. Without proper context, it guesses — and sometimes guesses wrong. Start with "Include source files with @file" before making broader code changes.

You're in the right place if...

  • !Generated code calls functions that don't exist
  • !Import references modules you never created
  • !TypeScript shows 'Property does not exist' errors

Why this happens

The AI generates code based on patterns from training data, not your actual codebase. Without proper context, it guesses — and sometimes guesses wrong.

Fix

1

Include source files with @file

Before asking Cursor to use a function, include the file where it's defined: '@src/lib/utils.ts use the formatDate function in the dashboard'.

2

Run TypeScript check

After generation, run:

npx tsc --noEmit
# Every hallucinated import shows as a TypeScript error
3

Tell Cursor to verify

After generating code, ask: 'Check that every function call in this file actually exists in the codebase. List any that might be hallucinated.'

Prevent this next time

Always include relevant files with @file. Use @codebase for complex tasks. Run npx tsc --noEmit after every generation.

Frequently Asked Questions

It generates based on training patterns, not your actual code. Without context, it guesses plausible-looking function names.

Always use @file to include relevant source files. Hallucinations drop by 90% with proper context.

Related fixes

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