The Composer Prompt Template That Actually Works

The difference between Composer producing exactly what you wanted and producing vague, wrong code comes down to how you write the prompt. Here is the exact template that experienced Cursor users rely on.

Most disappointment with Composer traces back to one cause: the prompt was too vague. Composer is extraordinarily capable when you tell it precisely what you want, and frustratingly hit-or-miss when you leave it to guess. The good news is that writing effective Composer prompts is a learnable skill with a clear structure.

The Five-Part Template

The template that consistently produces good results has five parts: state the goal, reference the files, specify the pattern to follow, add the constraints, and define how to verify success. Filling each slot explicitly almost always beats a free-form request.

The full pattern looks like this: "[Goal] in [target files]. Use [existing pattern or dependency]. With [specific constraints]. Verify by [verification method]." Each part eliminates a category of guesswork the AI would otherwise have to do, and every piece of guesswork is a chance to get it wrong.

Part 1: State the Goal Explicitly

"Make X better" is not a goal; it is a wish. "Add rate limiting to the login route" is a goal. The clearer and more concrete the goal, the better Composer performs. Vague goals force the AI to interpret what you want, and its interpretation may not match yours.

Part 2: Reference the Files with @

Do not make Composer guess which files matter. Use @ to point directly at them: "@auth/login.ts and @middleware/rateLimit.ts". This both focuses the AI's attention and ensures it reads the actual current content of those files rather than assuming what they contain.

Part 3: Specify the Pattern to Follow

Most codebases have established patterns. Point Composer at them: "use the existing rate-limit middleware pattern from @middleware/rateLimit.ts." This keeps new code consistent with your conventions instead of introducing a different style the AI happens to prefer.

Part 4: Add Concrete Constraints

Specifics matter. "Limit to 5 attempts per minute per IP, return a 429 status with a Retry-After header." Without constraints, the AI picks defaults that may not match your requirements. With them, you get exactly the behaviour you specified.

Part 5: Define Verification

End with how success is measured: "add tests in @tests/auth/login.test.ts covering the rate limit behaviour." This tells Composer not just to implement but to make the implementation verifiable, and it gives you an immediate way to confirm the change works.

A Complete Example

Putting it together: "Add rate limiting to the login endpoint in @auth/login.ts. Use the existing rate-limit middleware from @middleware/rateLimit.ts. Limit to 5 attempts per minute per IP, return a 429 status with a Retry-After header when the limit is hit. Add tests in @tests/auth/login.test.ts." Composer can execute this end-to-end because nothing is left to guesswork. Save your best prompts; Cursor remembers recent ones, and they become reusable templates for similar future tasks.