langobs-mcp

MCP server for LangObs — zero-code observability for any MCP-compatible agent (Claude Desktop, Cursor, Windsurf, etc.).

Any agent that supports MCP can send traces to LangObs without installing the Python or TypeScript SDK.

Install

pip install langobs-mcp

Prerequisites

Start the LangObs server:

pip install langobs-server
langobs-server

Configure in your MCP client

Claude Desktop (~/Library/Application Support/Claude/claude_desktop_config.json)

{
  "mcpServers": {
    "langobs": {
      "command": "langobs-mcp"
    }
  }
}

Cursor / Windsurf

Add to your MCP server config:

{
  "langobs": {
    "command": "langobs-mcp"
  }
}

Tools Exposed

Once connected, your MCP agent can call these tools:

How It Works

The MCP server receives tool calls from your agent and forwards them to the LangObs HTTP server (http://localhost:8766). Events appear in the dashboard in real-time.

Agent → MCP call → langobs-mcp server → HTTP POST → LangObs server → Dashboard

Example Usage (inside a Claude conversation)

Once the MCP server is connected, Claude can instrument its own tasks:

1. Call langobs_start_session → get session_id
2. For each tool call: langobs_report_trace(session_id, event_type="tool_call", ...)
3. For each LLM decision: langobs_report_trace(session_id, event_type="decision", ...)

Open http://localhost:5173 to watch the trace build in real time.

License

MIT