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Kai Viertel for SendSeven

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One REST API for 8 messaging channels: now with MCP access for AI agents

Every messaging channel has its own API, its own SDK, its own webhook format. Wire up WhatsApp, then SMS, then email, then Instagram… and you've built four integrations that all behave differently.

We built SendSeven so you don't have to: one REST API for 8 channels — WhatsApp, SMS, email, Instagram, Messenger, Live Chat, Telegram and Browser Push.

Send on any channel

curl -X POST https://api.sendseven.com/api/v1/messages \
  -H "Authorization: Bearer $SENDSEVEN_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{
    "channel_id": "b1f2c3d4-…",
    "to": "+4915112345678",
    "message_type": "text",
    "text": "Hi Anna! Your order #4821 has shipped."
  }'
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That channel_id points at one channel you connected (here a WhatsApp number). Want to send over Telegram or SMS instead? Change that one field. Every channel gets its own id — one endpoint, one payload shape, eight channels.

Two-way by default: webhooks

Sending is half the story. Every inbound message and status change is pushed to your endpoint in real time:

  • message.received · message.sent
  • message.delivered · message.read · message.failed
  • channel.created · channel.updated (health & alerting)

So you build real conversations — auto-replies, routing, your own bot — not just fire-and-forget.

The fun part: hand it to an AI agent over MCP

Here's what we most want you to try: SendSeven ships an MCP server at mcp.sendseven.com. Point any MCP-compatible client — Claude, Cursor, your own agent — at it, authorize over OAuth, and your agent can send and handle messages across every channel as a first-class tool. EU-hosted.

"Message the customer on WhatsApp that their order shipped." → your agent just does it. No glue code.

Built for people who ship

  • OpenAPI 3.0 spec + real-time webhooks
  • Multi-tenant Tenants API — isolated workspaces per customer, ideal for embedding SendSeven into your own product
  • Zapier & n8n when you'd rather not write code
  • EU-hosted (Frankfurt), GDPR-compliant, made in Germany
  • No per-seat fees, unlimited users, inbound is free

Try it

API Only starts at €9/channel/month, with a 14-day free trial — 100 test messages, no credit card. Grab a token and send your first cross-channel message in minutes:

What would you wire an AI agent up to first? Tell us in the comments — we'd love to see what you build (or break).

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