Kairo

Semantic code intelligence for AI agents — an MCP server powered by Tantivy.

Kairo fills the gaps that AI coding agents (Claude Code, Copilot, etc.) can't cover natively:

• Concept search — find code by meaning, not just keywords (BM25 + vector hybrid)
• Dependency graph — understand module dependencies, detect cycles, trace import paths
• Impact analysis — predict what breaks when you change a file (transitive propagation)
• File watcher — real-time incremental indexing as you edit

Install

# From source (requires Rust toolchain)
cargo install --git https://github.com/Meshyarn/kairo.git

# Or clone and build
git clone https://github.com/Meshyarn/kairo.git
cd kairo
cargo build --release
# Binary: target/release/kairo

MCP Configuration

Claude Code

Add to .claude/settings.json (project) or ~/.claude/settings.json (global):

{
  "mcpServers": {
    "kairo": {
      "command": "kairo",
      "args": []
    }
  }
}

Claude Desktop

Add to claude_desktop_config.json:

{
  "mcpServers": {
    "kairo": {
      "command": "/path/to/kairo",
      "args": ["/path/to/your/project"]
    }
  }
}

Kairo indexes your project on first use. No further configuration needed.

Optional: Vector Embeddings

Kairo includes a bundled bge-small-en-v1.5 model for hybrid search. If installed from source without Git LFS, enable it with:

kairo_status(action: "download-model")
kairo_status(action: "reindex")

Tools

kairo_search

Hybrid semantic search (BM25 + vector, fused with RRF). Use when Grep misses results.

kairo_search(query: "retry logic with backoff")
kairo_search(query: "authentication middleware", scope: "code")
kairo_search(query: "API rate limiting", limit: 5)

kairo_graph

Query the project dependency graph.

kairo_graph(operation: "deps", file: "src/mcp/mod.rs")
kairo_graph(operation: "dependents", file: "src/common/fs.rs")
kairo_graph(operation: "cycles")
kairo_graph(operation: "path", file: "src/main.rs", target: "src/common/fs.rs")
kairo_graph(operation: "impact", file: "src/common/fs.rs")

kairo_status

Check index health, trigger rebuilds, or download the embedding model.

kairo_status()
kairo_status(action: "reindex")
kairo_status(action: "download-model")

Supported Languages

Import extraction and dependency graph support:

Search indexing covers 35+ file extensions (all major languages, config files, docs).

Architecture

Single Rust binary (~26MB). No runtime dependencies.

• Search: Tantivy BM25F + bge-small-en-v1.5 vectors (384-dim), RRF fusion (k=60)
• Graph: regex-based import extraction, adjacency list, BFS/DFS
• Watcher: notify v7, 150ms debounce, incremental index + graph updates
• Protocol: rmcp 0.16, JSON-RPC 2.0 over stdio

License

MIT