Codebase AI Assistant and AI Codebase Explainer for GitHub Teams

A codebase AI assistant is an AI tool that answers questions about your specific source code. It indexes the repository, finds the files that relate to your question and passes them to a language model that writes the answer. The difference from a general chatbot is the index: without it, the model only sees what you paste in.

The good ones show their work. Every answer should point to file paths and line ranges, because an explanation you cannot check is not much use when you are about to change production code.

Yes, within limits. No model reads a large repository in one go, so the assistant indexes every file and retrieves the most relevant chunks for each question. That works well for questions about flows, rules and structure. It works less well for questions that need every file at once, such as "list every place that touches the users table", where a keyword search is still the better tool.

CodeIndex handles both sides. Search mode returns up to 50 matching chunks with file, lines and score, and explain and architecture modes turn those chunks into a written answer.

Give it an index, not a prompt. Copying files into a chat window works for one function and breaks down for a real repository. A codebase AI assistant connects to GitHub, indexes the branch you choose and refreshes the index when you reindex, so every question starts from the current code.

Then ask specific questions. "How does billing work" gets a vague answer from any tool. "What happens when a Stripe webhook for a failed invoice arrives" gets the handler, the retry rule and the email it sends.

It is as safe as the vendor's access model, so check three things before you connect a repository: which repositories the tool can read, who on your team can query them, and what happens to the index when you delete a repository or cancel. In CodeIndex you choose the repositories when you connect GitHub, only members of your team can query them, and API keys can be revoked at any time.

If your security team needs SSO and a long audit trail, those are on the Enterprise plan, with audit logs kept for 365 days.

An AI coding assistant such as Copilot or Cursor is built to write code inside an editor, and it is priced per developer seat. A codebase AI assistant is built to explain and find code for anyone who needs to understand it, and the useful pricing for that is per team.

Many teams run both. Developers keep their coding assistant, and the shared codebase assistant covers onboarding, QA, support and product questions that would otherwise need a seat each or an engineer's time.