MCP

Sir Bone is a generic Model Context Protocol client. It spawns MCP servers over stdio at startup, in the background, and registers their tools before the first turn.

Where servers are declared

• Global — mcpServers in ~/.sirbone/config.json
• Per-project — ./.mcp.json

The two are merged per server name; on a name collision the per-project entry wins.

{
  "mcpServers": {
    "filesystem": {
      "command": "npx",
      "args": ["-y", "@modelcontextprotocol/server-filesystem", "/path/to/project"]
    }
  }
}

Naming

Each remote tool is registered as mcp__<server>__<tool> so it never collides with a built-in tool. From the agent’s perspective it’s just another tool, subject to the same permission pipeline.

Lifecycle

Servers are launched asynchronously at startup so they don’t block the first prompt; their tools become available once the handshake completes (before the first turn runs).