Three prompts you can paste to Copilot/ChatGPT:

1) Candidate finder: 'Scan this file and list 8–12 extraction candidates (start/end lines). For each list used locals, side effects, and minimal safe-extract rationale.'

2) Extractor: 'Convert lines X–Y into a function: signature, docstring, explicit inputs/outputs, required refactors, and a one-line patch to replace original code.'

3) Verifier: 'Generate pytest cases and snapshot tests that compare return values, stdout, mutated globals, and performance before/after extraction.'

Verification steps: create a branch, run tests, run mypy/flake8, inspect git diff, run integration snapshots and perf check.

Try GitHub Copilot for in-editor extraction suggestions: Compare GitHub Copilot and Cursor