Basic Examples

Single-File Refactor

# Before: utils.py
def process_data(input):
    result = []
    for item in input:
        result.append(item*2)
    return result

gptdiff "Convert loop to list comprehension" utils.py --apply

# After: utils.py
def process_data(input):
    return [item*2 for item in input]

Multi-File Rename

gptdiff "Rename UserController to AccountController" \
    app/controllers/user_controller.py \
    test/controllers/test_user_controller.py \
    docs/api.md --apply

Full-Stack Type Safety

gptdiff "Add Python type hints throughout codebase" \
    --model deepseek-reasoner \
    --temperature 0.3 \
    --apply

Legacy Modernization

gptdiff "Convert string formatting to f-strings" src/ --apply

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Ready for More?

These examples show what GPTDiff can do with a single command. But the real power comes from running it continuously.

while true; do
  gptdiff "Improve code quality" --apply
  sleep 5
done

Let GPTDiff work on your codebase while you sleep. Each cycle finds the next improvement, applies it, and continues—test coverage expands, tech debt shrinks, security hardens automatically.

See Agent Loops Guide → for ready-to-use automation recipes.