How do I install Mailbuttons?

Copy the http config for Cursor, Claude Desktop, Claude Code, or VS Code on this page. It uses the publisher's install, not a PlugMCP proxy.

Does Mailbuttons need an API key?

The publisher lists these environment variables: MAILBUTTONS_API_KEY, MAILBUTTONS_API_URL.

What transport does Mailbuttons use?

Mailbuttons is reached over HTTP.

When was Mailbuttons last checked?

Last checked 2026-11-08. Governed email for AI agents: a sandbox inbox to read and send from, human approval to go external.

Mailbuttons MCP server

Power your agent

Add this server

The publisher's own URL. Not a PlugMCP endpoint.

Add to Cursor Add in Claude Add to VS Code Run on PlugMCP

Host a copy with our keys and logs.

Server URL

https://mailbuttons.com/api/v1/mcp/rpc

Credentials from the publisher

MAILBUTTONS_API_KEY — A scoped Mailbuttons MCP token (mb_sandbox_...). Sandbox-by-default; external send requires human promotion.
MAILBUTTONS_API_URL — Backend base URL. Defaults to https://mailbuttons.com; set for self-hosted or local.

The Claude button above opens Claude with the name and URL filled in. You still confirm it there.

shClaude Code

1claude mcp add --transport http com.mailbuttons-mcp-server https://mailbuttons.com/api/v1/mcp/rpc

Run in a terminal.

jsonClaude Desktop

1{2  "mcpServers": {3    "com.mailbuttons-mcp-server": {4      "command": "npx",5      "args": [6        "-y",7        "mcp-remote",8        "https://mailbuttons.com/api/v1/mcp/rpc"9      ]10    }11  }12}

claude_desktop_config.json

Remote · HTTPPublisher installStep-by-step: add this in Claude

Remote URL or a command on your machine? How the two installs differ

Run on PlugMCP

Host a copy with our keys and logs.

A new server you create. It is not this listing's official endpoint. Use the publisher install when you want their URL and their credentials.

Launch

Server facts

Remote

Transport: http
Version

Tools

No tool list yet. Remote servers get one after the first health check.

FAQ

Questions

Mailbuttons MCP server

Governed email for AI agents, over the Model Context Protocol. Give an agent a scoped mailbox where the server enforces the guardrails, not the prompt: sandbox-by-default inboxes, a policy gate on every send, and a tamper-evident audit log. External sending and scope changes are human-approved, never granted by the agent itself.

Use it

Hosted (recommended) — a streamable-HTTP endpoint served by the platform:

https://mailbuttons.com/api/v1/mcp/rpc Authorization: Bearer <your Mailbuttons MCP token> # mb_sandbox_... (or mb_prod_...)

Local (stdio) — run the npm package and let your agent launch it:

{ "mcpServers": { "mailbuttons": { "command": "npx", "args": ["-y", "@mailbuttons/mcp-server"], "env": { "MAILBUTTONS_API_KEY": "mb_sandbox_..." } } } }

Get a scoped token from the dashboard or POST /api/v1/mcp/sandbox-inboxes. Sandbox tokens can never send externally until a human promotes them.

What the server enforces

Inbound — a per-mailbox sender policy, fail-closed: mail from strangers bounces by default, so nobody can prompt-inject your agent just by emailing it.

Outbound — a recipient blocklist the agent can read but not change; a blocked send returns a normal {"status":"blocked"} result, not an error.

Caps + audit — per-account send caps and a hash-chained audit log that records refusals too.

Escalation — sending externally or widening scope is propose-only; a named human approves. The agent cannot approve its own request.

Install as an agent skill

This repo ships a root SKILL.md, so any skills-aware agent can add it:

npx skills add mailbuttons/mcp-server

Docs

Mailbuttons is a trading name of Code Cutter Limited (UK, no. 08453060). MIT licensed.

Add this server

Host a copy with our keys and logs.

Server facts

Tools

Questions

How do I install Mailbuttons?

Does Mailbuttons need an API key?

What transport does Mailbuttons use?

When was Mailbuttons last checked?

Documentation