Warm Inbox MCP Server

by warminbox Your server? Claim it

answering

Warm Inbox is answering right now. Last checked 7 min ago. Last commit 1 Nov 2026.

Email warm-up for AI builders: check deliverability, connect mailboxes, pause or tune warm-ups.

Uptime history 51 hours of history

51 hours agonow

100.0%

Uptime 24h

91 of 91 checks

—

Tools

hidden behind auth

234 ms

Response time

average over 24h

Stars

last commit 1 Nov 2026

Nothing serious here today

Today is the operative word: we check Warm Inbox every 15 minutes and re-read its code on every release. Watch it and you find out the day that stops being true.

Connect this server

Endpoint below is the one we actually reach during checks — not the one copied from a README. Last verified 7 min ago.

Claude Code Claude Desktop Codex Cursor VS Code

run in your terminal

claude mcp add mcp --transport http https://mcp.warminbox.org/mcp

Settings → Connectors → Add custom connector, then paste this address

https://mcp.warminbox.org/mcp

~/.codex/config.toml

[mcp_servers.mcp]
url = "https://mcp.warminbox.org/mcp"

.cursor/mcp.json

{
  "mcpServers": {
    "mcp": {
      "url": "https://mcp.warminbox.org/mcp"
    }
  }
}

.vscode/mcp.json

{
  "servers": {
    "mcp": {
      "type": "http",
      "url": "https://mcp.warminbox.org/mcp"
    }
  }
}

This endpoint answered with an authorization challenge. The server is running, but you need an API key from its owner to call it.

Endpoints

URL	Transport	State	Latency	Checked
https://mcp.warminbox.org/mcp	streamable-http	needs key	72 ms	7 min ago

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Warm Inbox — questions

Answers built from our own checks of this server.

Why is there no tool list for Warm Inbox?

The server answered our handshake with an authorization challenge, so it is running — but it will not describe its tools to an anonymous client. To see them you need to connect with your own credentials. We record it as alive, not as broken: 100.0% of checks in the last 24 hours got a reply.

Is Warm Inbox working right now?

We send a real MCP handshake every 15 minutes. Over the last 24 hours 91 of 91 checks got a reply (100.0%), average response time 234 ms. The bar chart above shows every period we have measured.

How do I connect Warm Inbox?

Copy the ready config from this page. We generate it for Claude Code, Claude Desktop, Codex, Cursor and VS Code, each in the form that client actually reads. It is a remote server, so there is nothing to install — the client connects to the address. You will need your own key: it refuses anonymous clients.

Does Warm Inbox need an API key?

Yes. Every time we knock, Warm Inbox answers with an authorization challenge instead of its tool list — that is how we know it is running and gated rather than broken. Bring your own credentials and it will talk.

How fast is Warm Inbox?

It answers our handshake in 234 ms on average, which is faster than 60% of all working MCP servers we measure. The comparison comes from our own checks across the whole registry, every 15 minutes.

Is Warm Inbox open source?

The code is open source: it is published under the MIT licence, written in TypeScript and 0 stars on GitHub. The licence covers the code in the repository, not the hosted service at mcp.warminbox.org, which runs on its operator's own terms.