Google currently offers free API access to the Gemini 1.5 Pro model. This is the most capable free model to use with aider, with code editing capability that’s comparable to GPT-3.5. You’ll need a Gemini API key.

pip install aider-chat

export GEMINI_API_KEY=<key> # Mac/Linux
setx   GEMINI_API_KEY <key> # Windows

aider --model gemini/gemini-1.5-pro-latest

# List models available from Gemini
aider --models gemini/