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Devin

Connect Devin to MailBlastr over MCP so the agent can send emails, manage contacts, and run campaigns.

Devin is an autonomous AI software engineer that can connect to external services through MCP (Model Context Protocol) servers. Adding MailBlastr's MCP server gives Devin native access to send emails, manage contacts and campaigns, verify domains, and more. For the full list of capabilities, see the MCP server overview.

Prerequisites

A Devin account with access to the Settings menu.
A MailBlastr API key.
A verified domain.

1. Open Connections > MCP Servers

In Devin, open Settings from your account dropdown. In the sidebar click Connections, select the MCP Servers tab, then click Add a custom MCP.

2. Add the MailBlastr MCP configuration

Click Import JSON and paste the following configuration into the modal:

{
  "mcpServers": {
    "mailblastr": {
      "command": "npx",
      "args": ["-y", "mailblastr-mcp"],
      "env": {
        "MAILBLASTR_API_KEY": "mb_xxxxxxxxx",
        "SENDER_EMAIL_ADDRESS": "hello@yourdomain.com"
      }
    }
  }
}

3. Update the environment variables

MAILBLASTR_API_KEY — delete the inline value and add it as a secret instead (next step).
SENDER_EMAIL_ADDRESS — set this to a sender address on a domain you've verified.

4. Add the API key as a secret

Add MAILBLASTR_API_KEY as a Devin secret and click Save secret to confirm. You can create a new API key any time in the dashboard.

Store the API key as a secret rather than inline in the MCP config so it isn't exposed in plaintext.

5. Enable and test

Add a description, click Install and Enable, and confirm in the dialog. Devin installs the server and marks it connected. Then ask Devin to send a test email:

Send a test email to delivered@example.com using the MailBlastr MCP server.
Subject: "Hello from Devin".

Devin calls the MailBlastr MCP server and confirms the send.