Agent skill · software engineering · agentmail-to
agentmail-mcp
Configure or troubleshoot the hosted AgentMail MCP server for Codex, Claude Code, Cursor, or another Streamable HTTP MCP client. Use for installation, OAuth, API-key headers, connection failures, or MCP tool discovery. Do not use when the connection already works and the user just wants to send, check, or manage mail — use the sibling action skills for that.
Why this skill is useful
Provides specific configuration patterns and troubleshooting steps for the AgentMail MCP server that the AI wouldn't reliably generate on its own.
What it needs
Requires npm, python installed locally. About 2k tokens when loaded. Last updated 2026-07-21. 21 stars on the source repository.
What this skill does
AgentMail MCP Prefer the hosted Streamable HTTP server: 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. Claude Code can also install it directly: 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/claudedesktopconfig.json (macOS) or %APPDATA%/Claude/claudedesktopconfig.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 AGENTMAILAPIKEY and send it as a header: 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. Stdio Compatibility For a stdio-only client, use the supported npm or PyPI agentmail-mcp package. Both are thin stdio bridges to the same hosted runtime: they discover tools dynamically and carry no separate AgentMail tool logic of their own. Verify 1. …
How to use it
Reference it in AdaL, Claude Code, Cursor or any coding agent — nothing to install:
@skills agentmail-to/agentmail-mcp