Atomic Mail vs MCP Hey

In-depth architectural comparison of the Atomic Mail and MCP Hey MCP servers. Compare execution transports, security boundaries, tool capabilities, quality scores, and ready-to-paste client installation snippets for Claude, Cursor, Windsurf, and VS Code.

Which MCP Server Should You Choose?

Choose Atomic Mail when:

• You need dedicated capabilities in the Communication domain.
• You prefer local stdio subprocess transport architecture.
• Your security boundary fits: No auth required (Free / Open Source).
• Primary tools included: PoW-based inbox registration, JMAP email operations, MCP stdio transport.

Explore Atomic Mail Details

Choose MCP Hey when:

• You need dedicated capabilities in the Communication domain.
• You prefer local stdio subprocess transport architecture.
• Your security boundary fits: other (Free / Open Source).
• Primary tools included: Read email across Hey mailbox areas, Search with a local SQLite full-text index, Send, reply to, and forward messages.

Explore MCP Hey Details

Feature & Specification Comparison

Specification	Atomic Mail Communication	MCP Hey Sealjay Communication
Summary	Programmable email inbox for AI agents — JMAP, PoW auth, stdio MCP server.	Local MCP server for Hey.com email. Read, search, send, reply, and manage the screener via locally cached session from Hey's webview auth.
Category & Scope	Communication	Communication

Tools & Capabilities Breakdown

Ready-to-Paste Client Configurations

Paste either (or both) of these JSON server blocks into your client config file (e.g. claude_desktop_config.json or ~/.cursor/mcp.json).

{
  "mcpServers": {
    "atomic-mail": {
      "command": "npx",
      "args": [
        "-y",
        "--package=@atomicmail/agent-skill-github",
        "atomicmail"
      ]
    }
  }
}

{
  "mcpServers": {
    "sealjay-mcp-hey": {
      "command": "npx",
      "args": [
        "-y",
        "sealjay-mcp-hey"
      ]
    }
  }
}

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