SendSoon AI MCP

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Use SendSoon email, IP lookup, and file-to-Markdown capabilities from Codex, Claude, Cursor, and other AI agents.

Configure it once, then describe tasks in natural language. You usually do not need to mention SendSoon in every prompt.

What you can do

Related MCP server: Gmail & Google Docs MCP Server

Try it in Google Colab

Skip local setup and try ip_lookup, markitdown_convert, and send_email in the browser.

The notebook calls the same SendSoon HTTP APIs used by these MCP tools. To use them from Cursor, Claude, or Codex, continue with the local MCP setup below.

Step 1: Check the requirements

• Node.js 20 or later

• Codex, Claude, Cursor, or another client that supports local stdio MCP servers

There is nothing to install by hand. Every configuration below starts the server with npx, which downloads @sendsoon/ai on first use and reuses the cached copy afterwards.

If you prefer to run from a local checkout, see Build from source.

Step 2: Prepare the configuration

All clients use the same environment variables:

Never commit a real Key to Git or share it with anyone.

Get an API Key

1. Sign up or sign in on the SendSoon registration page.

2. Open Profile and generate a Key in the API Key section.

3. Copy the one-time ssk_live_... Key immediately and enter it as SENDSOON_API_KEY in your MCP configuration.

4. Save the configuration and restart your MCP client. Requests with a valid Key do not use the anonymous IP daily quota.

If the anonymous quota is exhausted, send_email will tell you to register and configure a Key. An invalid or revoked Key is rejected and does not fall back to the anonymous quota.

Step 3: Choose your client

Cursor

Open Settings > Tools & MCP in Cursor and add an MCP server. You can also save the following configuration as .cursor/mcp.json in your project or ~/.cursor/mcp.json in your user directory:

{
  "mcpServers": {
    "sendsoon": {
      "command": "npx",
      "args": ["-y", "@sendsoon/ai"],
      "env": {
        "SENDSOON_EMAIL_RECIPIENT": "<YOUR_EMAIL>",
        "SENDSOON_API_KEY": ""
      }
    }
  }
}

Use only one top-level mcpServers object. Save the file, reopen Cursor, and confirm that sendsoon is enabled.

Codex

Open the user configuration file at ~/.codex/config.toml and add:

[mcp_servers.sendsoon]
command = "npx"
args = ["-y", "@sendsoon/ai"]

[mcp_servers.sendsoon.env]
SENDSOON_EMAIL_RECIPIENT = "<YOUR_EMAIL>"
SENDSOON_API_KEY = ""

Save the file and reopen Codex. Use /mcp to confirm that sendsoon is connected. In the desktop app, you can also check Settings > MCP servers.

Claude Code

Replace the placeholder and run:

claude mcp add --transport stdio --scope user --env SENDSOON_EMAIL_RECIPIENT=<YOUR_EMAIL> sendsoon -- npx -y @sendsoon/ai

Run /mcp in Claude Code and confirm that sendsoon is connected. To use an API Key, add --env SENDSOON_API_KEY=<SENDSOON_API_KEY> before the sendsoon server name.

Claude Desktop

Open the configuration file from Settings > Developer and add:

{
  "mcpServers": {
    "sendsoon": {
      "command": "npx",
      "args": ["-y", "@sendsoon/ai"],
      "env": {
        "SENDSOON_EMAIL_RECIPIENT": "<YOUR_EMAIL>",
        "SENDSOON_API_KEY": ""
      }
    }
  }
}

Save the file, fully quit and restart Claude Desktop, and confirm that sendsoon appears in the tool list.

Other MCP clients

For Windsurf, Cline, Continue, or another client that supports local stdio MCP servers, enter:

Confirm that it works

Restart the client, open a new conversation, and enter:

Look up the location and ISP for 8.8.8.8.

The MCP connection works if the agent calls ip_lookup and returns the result.

To test email, enter:

Send a test email to <YOUR_EMAIL> with the subject “SendSoon MCP test” and the body “Configuration successful.”

The address must exactly match SENDSOON_EMAIL_RECIPIENT. Your client may ask for permission the first time a tool runs; approve it to continue.

Everyday examples

Look up information about 1.1.1.1.

Convert <YOUR_FILE_PATH> to Markdown and summarize the key points.

Send an email to <YOUR_EMAIL> with the subject “Meeting reminder” and the body “The meeting starts at 3 PM today.”

If the agent does not select a tool automatically, say:

Use the sendsoon MCP to complete this task.

You usually need this explicit instruction only on the first use.

Agent Skills

This repository also ships Agent Skills that teach agents when to reach for each tool and how to handle its error codes. In Claude Code, install them as a plugin:

/plugin marketplace add sendsoon/ai
/plugin install sendsoon-skills@sendsoon

You can also copy any folder under skills/ into .claude/skills/ in your project or ~/.claude/skills/ in your user directory.

Build from source

Only needed if you want to modify the server or run an unreleased revision. Requires pnpm 11.

git clone https://github.com/sendsoon/ai.git
cd ai
pnpm install
pnpm run build
pnpm run bundle

Then point your client at the built entry file instead of npx, using the absolute path printed by:

(Resolve-Path .\mcp\bin\sendsoon-mcp.mjs).Path.Replace('\', '/')

realpath ./mcp/bin/sendsoon-mcp.mjs

Use "command": "node" with that absolute path as the only argument. Run pnpm run check to lint and test your changes.

Official references

• OpenAI Codex: Model Context Protocol

• Anthropic: Claude Code MCP

• Cursor: Model Context Protocol

• Model Context Protocol

License

See LICENSE.