kairn — Claude Code MCP server: what it does, how to install
A local knowledge engine for AI agents. It stores connected facts and routes useful context into new sessions.
Open on GitHubWhat kairn does
kairn keeps agent knowledge in a local graph with typed links, source tracking, and FTS5 full-text search. Its context router starts with compact summaries and expands into details when the task calls for them. Stored experiences fade over time, while frequently used ones can become lasting knowledge.
The MCP server exposes 22 tools, including kn_judge for relationship decisions and kn_doctor for read-only health checks. Each workspace uses its own SQLite store. Team deployments can use JWT authentication and the owner, maintainer, contributor, and reader roles.
The PyPI route requires Python: run pip install kairn-ai, then register the server with claude mcp add kairn -- kairn serve --init ~/brain. Claude Desktop users can instead open the .mcpb bundle, which avoids a separate Python setup.
What it helps with
- carry decisions across agent sessions
- model dependencies as connected graph nodes
- retrieve context by topic and relevance
- keep workspace data isolated
- inspect the health of a local knowledge store
Example prompts for the agent
- Recall decisions and dependencies related to authentication.
- Check the health of this workspace’s knowledge store.
How to install kairn
Install
The MCP registry has no launch command for it: see the repository README
Step by step, with commands for each platform: How to add an MCP server to Claude Code, Codex, Cursor, VS Code, Gemini CLI and more
Questions about kairn
How do I install kairn in Claude Code?
Run pip install kairn-ai, then register the server with claude mcp add kairn -- kairn serve --init ~/brain. The first start creates the workspace and database.
What does kairn do?
It gives an AI agent a local knowledge graph, relationship search through FTS5, and staged context retrieval. Older experiences fade while frequently used knowledge can be retained.
Does kairn require Python?
Python is required for the PyPI installation route. Claude Desktop can use the .mcpb bundle without a separate Python setup.
