Free prompt optimiser
Coding Prompt Optimiser
Turn a vague coding request into a prompt with a stated language, constraints, edge cases and expected output — for any AI coding assistant.
Runs with Local Rules, free, in your browser — no sign-up needed.
What this optimiser checks
- Whether the language, runtime or framework is specified
- Whether inputs, outputs and edge cases are described
- Whether performance, style or dependency constraints are given
- Whether the requested output format (code only, with tests, with explanation) is stated
- Whether there's a way to verify correctness, such as example inputs and expected results
Example prompt
Write a function that validates an email address.
"Write a function that validates an email address" doesn't say which language, what counts as valid, or whether you want tests. Every AI model will answer it — with a different language, a different regex, and different edge-case handling every time you ask.
Local Rules rewrites coding prompts to name the language and runtime, list concrete edge cases (empty input, multiple @ symbols, internationalised domains), and specify whether you want the function alone, with unit tests, or with an explanation. Expert mode adds a validation section so the model states how its own answer should be checked.
Frequently asked questions
- Does this write the code for me?
- No — Local Rules improves the prompt you send to a coding assistant; it doesn't generate or execute code itself. Use the optimised prompt in ChatGPT, Claude, Gemini, or your own model of choice.
- Will it know my project's existing code style?
- No, because it never sees your codebase — it only sees the prompt text you paste. Mention your language, framework and style constraints in the prompt and the rewrite will fold them into the Requirements section.
- Can I use this for debugging prompts, not just new code?
- Yes. Paste the error and what you've tried; the Coding task type checks for the same structural gaps (language, expected vs. actual behaviour, constraints) whether you're generating or debugging.
Free — no sign-up needed. Bring your own key for direct AI analysis, or stay local.