n8n Email API for AI Agents

Where This Integration Stands

Straight answer first: there is no native Dead Simple Email node in n8n as of August 2026 — a native node is on our roadmap. But n8n's generic nodes cover the whole surface today, with no compromises: the HTTP Request node calls any endpoint of our REST API, the Webhook node receives our HMAC-signed inbound-email events, and the MCP Client Tool node gives AI Agent workflows the full 14-tool email toolset. The three recipes below are copy-paste ready.

Recipe 1: Create Inboxes and Send Email (HTTP Request Node)

Set up one reusable credential: in the HTTP Request node choose Generic Credential Type → Header Auth, name the header Authorization, and set the value to Bearer dse_your_api_key.

Create an inbox — each agent or workflow gets its own address:

Method:         POST
URL:            https://api.deadsimple.email/v1/inboxes
Authentication: Header Auth (Authorization: Bearer dse_your_api_key)
Body (JSON):
{
  "display_name": "n8n-agent"
}

The response includes inbox_id and the inbox's email address. Send an email from it in a second HTTP Request node, referencing the previous node with an n8n expression:

Method:         POST
URL:            https://api.deadsimple.email/v1/inboxes/{{ $json.inbox_id }}/messages
Authentication: Header Auth (same credential)
Body (JSON):
{
  "to": ["user@example.com"],
  "subject": "Your report is ready",
  "text_body": "The nightly workflow finished. Summary attached below."
}

Every other endpoint — replies, threads, bulk inbox creation, domains — works the same way; see the API reference.

Recipe 2: Trigger Workflows on Inbound Email (Webhook Node)

Turn any inbound email into a workflow run:

1. Add a Webhook node, method POST, and copy its production URL. Enable the Raw Body option — you'll need the exact bytes for signature verification.
2. Register the URL with one API call (or a one-off HTTP Request node):

curl -X POST https://api.deadsimple.email/v1/webhooks \
  -H "Authorization: Bearer dse_your_api_key" \
  -H "Content-Type: application/json" \
  -d '{
    "url": "https://your-n8n.example.com/webhook/abc123",
    "events": ["message.received"],
    "description": "n8n inbound email trigger"
  }'

The response includes a signing secret — shown once. Store it as an n8n environment variable (e.g. DSE_WEBHOOK_SECRET). From then on, every inbound email to any of your inboxes starts the workflow with the full message as JSON.

Verify the signature

Deliveries carry X-DSE-Webhook-Timestamp and X-DSE-Webhook-Signature headers, where the signature is sha256= followed by HMAC-SHA256 over timestamp.body. Drop a Code node right after the Webhook node:

const crypto = require('crypto');

const headers = $json.headers;
const rawBody = $json.body; // string — requires "Raw Body" enabled

const expected = 'sha256=' + crypto
  .createHmac('sha256', $env.DSE_WEBHOOK_SECRET)
  .update(`${headers['x-dse-webhook-timestamp']}.${rawBody}`)
  .digest('hex');

if (expected !== headers['x-dse-webhook-signature']) {
  throw new Error('Invalid webhook signature — dropping event');
}

return [{ json: JSON.parse(rawBody) }];

Anything downstream of this node is guaranteed to be a genuine Dead Simple Email event. Inbound messages are also scanned for prompt injection before delivery, with a risk level on the message object — useful if an AI Agent node acts on the content.

Recipe 3: Email Tools for AI Agent Nodes (MCP Client Tool)

n8n's AI Agent workflows can consume MCP servers directly through the MCP Client Tool node — no HTTP wiring per tool:

Endpoint:       https://api.deadsimple.email/mcp
Transport:      HTTP Streamable
Authentication: Bearer — your dse_ API key

Attach it to an AI Agent node and the agent discovers 14 tools: create_inbox, list_inboxes, delete_inbox, send_email, read_messages, read_message, reply_to_message, forward_message, wait_for_email, get_verification_code, get_verification_link, list_threads, read_thread, and get_usage. Use the node's tool filter to expose only what the agent should touch.

Frequently Asked Questions