Consider an alternative approach: chunk up and embed your entire codebase (dramatically cheaper) and insert it into a vector store. when you go to send a query, search the store and retrieve the most relevant chunks, and those are what you send with your query.

Optionally send other specific code alongside it.

This should be similar in quality and dramatically cheaper. It's quite doable with langchain, and you can use Chroma + DuckDB to avoid having to pay for Pinecone.

You could even maintain there vector store using git diffs to only update chunks that have changed.