MCP Server

kb-mcp runs as an MCP server when invoked with no arguments. It communicates over stdio using the JSON-RPC protocol.

Registration

Add to your project’s .mcp.json:

{
  "mcpServers": {
    "kb": {
      "command": "kb-mcp",
      "args": []
    }
  }
}

The binary must be in your PATH (install via just install-server or cargo install --path crates/kb-mcp-server).

Startup

On startup, kb-mcp:

1. Loads collections.ron (see Configuration)
2. Scans all collection directories for .md files
3. Builds the BM25 search index in memory
4. Starts the MCP stdio transport

Logs go to stderr. Startup typically takes <1s for ~200 documents.

Agent Workflow

A typical agent session:

1. Call list_sections to see what’s available
2. Call search to find relevant documents
3. Call kb_context on promising results to scan frontmatter + summary
4. Call get_document only on documents worth reading in full
5. Call kb_write to capture new knowledge (writable collections only)
6. Call reindex after creating new files mid-session