agentmail-mcp

AgentMail MCP

Prefer the hosted Streamable HTTP server:

https://mcp.agentmail.to/mcp

It avoids a local Node.js process and the slower release cadence of the published local MCP package.

Claude Code, Codex, and Cursor

Use OAuth. Do not put an empty API key in the configuration.

{
  "mcpServers": {
    "agentmail": {
      "type": "http",
      "url": "https://mcp.agentmail.to/mcp"
    }
  }
}

Claude Code can also install it directly:

claude mcp add --transport http agentmail https://mcp.agentmail.to/mcp

Complete the browser sign-in on first connection. Multi-organization OAuth sessions can use the server's organization-selection tools.

Per-client configuration

Add the same type: http server entry to the client's MCP config file:

• Cursor: .cursor/mcp.json
• VS Code: .vscode/mcp.json
• Windsurf: its MCP config file
• Claude Desktop: ~/Library/Application Support/Claude/claude_desktop_config.json (macOS) or %APPDATA%/Claude/claude_desktop_config.json (Windows)

Auth options

• OAuth — browser-based sign-in, for clients that support remote MCP OAuth. Use the bare URL with no credentials.
• x-api-key header — recommended for clients without OAuth support (see below).
• Authorization: Bearer <am_...> header — an alternative header form some clients require.
• apiKey query param — supported but not recommended; prefer a header so the key doesn't end up in logs or history.

For a Streamable HTTP client that cannot complete OAuth, export AGENTMAIL_API_KEY and send it as a header:

{
  "mcpServers": {
    "agentmail": {
      "type": "http",
      "url": "https://mcp.agentmail.to/mcp",
      "headers": {
        "x-api-key": "${env:AGENTMAIL_API_KEY}"
      }
    }
  }
}

Avoid query-string credentials when header authentication is available.

Tool Discovery

MCP clients get the tool catalog and schemas live from the hosted runtime; do not rely on a copied tool count. The same generated contract is published at https://github.com/agentmail-to/agentmail-mcp/blob/main/mcp-manifest.json — treat the hosted runtime plus that manifest as the authoritative catalog. OAuth sessions can surface extra organization-selection tools beyond the base set.