Claude Code
Best for: Serious work on real repos
Anthropic's agent for your terminal, IDE and desktop. Reads the whole repo, runs commands and tests, and handles large multi-file changes well.
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Refactor code safely with an AI agent
“This code works but it's a mess, and I'm scared to touch it.”
Give the agent a measurable goal, a test baseline and a stopping rule. It makes one small change at a time and keeps only what passes.
Fix it yourself in 3 steps
- Make sure tests (or at least a run script) pass before you start, and commit.
- Give the agent a specific goal and the loop prompt below.
- Review the diff and the agent's list of what it tried and rejected before merging.
Copy this prompt
Refactor [file/module] to [measurable goal, e.g. 'split the 600-line function into units under 80 lines']. First run the tests and record the baseline. Then make one small change at a time without changing public behavior, rerunning the same tests after each. Keep only changes that pass. Stop after 5 rounds, when the goal is met, or if a change needs my approval. Finish with the diff summary, test results, and what you tried and rejected.
Fill in the [brackets]. Each prompt says when the AI should stop, so it doesn't wander off.
Inspired by real examples collected at signals.forwardfuture.com.
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