MCP servers

Every project can have its own MCP servers — a task tracker, a database, a browser. blu passes them to the agent when it opens a session; the agent itself starts and talks to them, with your login shell’s environment, so npx and uvx are found.

Adding a server

Project editor ▸ MCP servers ▸ Add an MCP server… (shown for real agents only). A server is either:

• a command with arguments and environment variables, for example npx -y some-mcp-server;
• a URL (Streamable HTTP) with headers, for example https://example.com/mcp.

The identifier becomes the tools’ prefix for the agent (mcp__<id>__…) and can’t be changed later.

Note

A remote server is passed only to an agent that supports HTTP MCP servers; otherwise the task’s progress says so.

Secrets

Mark a value as secret (Keep the value in this Mac’s Keychain) and it goes to the macOS Keychain, not to the project settings, which may sync through iCloud. A missing secret doesn’t block the server: the task’s progress names the value that’s missing.

Changing the list of servers reopens the agent’s session with the new list; the conversation’s history stays.