You're right that you can chat with files using Gemini or a codegen'd RAG pipeline, and that does work well for a lot of teams.

The problem that Captain really addresses comes when production pipelines need to run continuously over large file corpora with fast, incremental indexing, and reliable latency. The maintenance required in these situations is often quite significant.

Captain focuses specifically on making sure the retrieval layer can operate smoothly so folks don't have to scale & maintain the infrastructure themselves.