"National Rail" matching MCP connectors:

PhoboMail gives AI agents their own @phobomail.com email address with zero human involvement. Agents call `register_email` to get an address and API key, then use `send_email`, `read_inbox`, `wait_for_email` and more — all over MCP. Ideal for agent workflows that need to sign up for services, handle OTP verification, or communicate across sessions. Hosted on Cloudflare.

AI-native settlement rail + intelligence oracle for autonomous agents. x402, Base mainnet, 81 tools.

Agentic rails for complex workflows with receipts, fees, and MCP tool access.

A paid remote MCP for OpenAI Codex agent coordination MCP, built to return verdicts, receipts, usage