[UmGuys]

I'm not familiar with Claude's architecture, but I'd be surprised if it doesn't index your codebase for semantic search with the explore feature it has. How else would they find context? They already have a semantic search tool -- which is rag.

[simonw]

Claude Code doesn't do anything with semantic search or embeddings out of the box. They use a simple grep tool instead.

Neither does OpenAI's Codex CLI - you can confirm that by looking at the source code https://github.com/openai/codex

Cursor and Windsurf both use semantic search via embeddings.

You can get semantic search in Claude Code using this unofficial plugin: https://github.com/zilliztech/claude-context - it's built by and uses a managed vector database called Zilliz Cloud.

[UmGuys]

That's shocking to me. Although it does make sense from a UX perspective as indexing can take minutes depending on the setup.