Simon Willison’s Weblog

AI-powered Git Commit Function (via) Andrej Karpathy built a shell alias, gcm, which passes your staged Git changes to an LLM via my LLM tool, generates a short commit message and then asks you if you want to "(a)ccept, (e)dit, (r)egenerate, or (c)ancel?".

Here's the incantation he's using to generate that commit message:

git diff --cached | llm "
Below is a diff of all staged changes, coming from the command:
\`\`\`
git diff --cached
\`\`\`
Please generate a concise, one-line commit message for these changes."

This pipes the data into LLM (using the default model, currently gpt-4o-mini unless you set it to something else) and then appends the prompt telling it what to do with that input.