Send email from Claude, Cursor & your agents.
send16-mcp is a Model Context Protocol server with 79 tools for email — send, segment, template, automate, and report. Point any MCP client at it and your agent can run the whole platform. No glue code.
{
"mcpServers": {
"send16": {
"command": "npx",
"args": ["-y", "send16-mcp"],
"env": { "SEND16_API_KEY": "sk_live_..." }
}
}
}Same three lines for Cursor (.cursor/mcp.json), Windsurf, VS Code & Claude Code.
The part nobody else does
An agent's first email, with zero DNS.
Every other email API blocks an unattended agent on step one: verify a domain first. Send16 ships a sandbox sender — a blind agent can send a real, delivered email in three calls, no human, no setup.
whoami
The agent asks who it is. Send16 returns the workspace and a sandbox_recipient — the one address it can send to with no setup.
send
It sends from [email protected] to that address. No domain, no DNS, no DKIM — it just delivers.
verify
It checks delivery status by log id: sent → delivered. A real email, in the inbox, unattended.
79 tools, one server
Everything your agent needs to run email.
Send
Transactional and marketing email — single, batch, scheduled, with attachments and templates. One call, one log row.
Contacts & audiences
Create, search, import and segment contacts. Manage audiences, tags, custom fields and subscription topics.
Campaigns & automations
Draft campaigns, send tests, run broadcasts, and drive automations — the whole marketing layer over MCP.
Deliverability
List domains, check SPF/DKIM/DMARC health, track IP warming and sending capacity before you scale a send.
Inbox & webhooks
Read and manage transactional replies; create, list and rotate HMAC-signed outgoing webhook endpoints.
AI templates
Generate on-brand HTML email from a prompt — type, style, brand colour and company name in, ready template out.
No install? Use the hosted endpoint.
For clients that only speak remote MCP — Claude web connectors, custom GPTs — point them at the hosted server and authenticate with your key. It's multi-tenant, so your key scopes every call to your workspace.
Get a key and connect.
Free tier covers 1,000 emails/month. No credit card. First send in under a minute.