Callimachus MCP server

Callimachus is a local helper that keeps a searchable copy of your past conversations with coding assistants like Claude Code, Codex, and Cursor. Once it is connected, your AI can look back through that history when you ask it something. It is handy if you keep re-explaining the same project or forget how you solved a problem last month.

What this MCP server does

You ask your AI a question about your past work, like whether you have dealt with a certain error before. The AI sends that question to the Callimachus helper running on your computer. The helper searches its local index of your old conversations, using both keywords and meaning-based matching. It sends back the matching threads, decisions, or notes. Your AI then turns that into an answer for you in the chat.

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What you can do with it

• Search your past coding conversations by keyword or topic
• Find threads that touched a specific file path
• Recall decisions and gotchas recorded for a project
• List open TODOs from your history
• Ask a question and get a cited answer from your own threads
• Check whether a decision was already settled before you change it
• Save a snapshot of a session so you can pick it up later

Try asking your AI

• “Have I solved this database migration problem before?”
• “What did we decide about the vector index setup?”
• “Show me threads that touched embed/mod.rs”
• “What open TODOs do I have in this project?”

What it gives back to you

You get back a list of matching threads with short details, or a written answer with citations pointing to the threads it used. It can also return lists of decisions, gotchas, TODOs, or snapshots. Everything shows up right in your chat as text you can read and copy.

Before you start

Who it's for

Developers and anyone who works with coding assistants daily and wants their AI to remember past sessions.