Mailhook Trigger

mh-x7k2m9qf4a3vbn8c@mailhook.spojit.com

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Mailhook vs. Email trigger

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Setup

1. Select the trigger node, set Trigger Type to Mailhook.
2. Optional: enter an Address prefix (see below). Leave it empty for the default mh.
3. Click Generate email address. The address appears immediately with a copy button.
4. Point mail at it: add it to a vendor’s notification settings, create a forwarding rule in your mail client, or use it directly as a “send results here” address in another system.
5. Optional: add a From allowlist or Subject regex filter, then Save workflow.

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The address

• The random part is 16 characters of cryptographically random base32. This is what makes the address unguessable; treat it like a capability. Anyone who knows the full address can start the workflow (subject to your filters).
• The prefix is cosmetic and yours to choose: 1 to 24 lowercase letters, digits, or hyphens. invoices, support-intake, crm-sync. Defaults to mh. A recognizable prefix makes forwarding rules and audit logs easier to read.

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Filters

• From allowlist: comma-separated patterns. @acme.com matches any sender at acme.com; orders@vendor.com matches the exact address. Multiple patterns are OR’d.
• Subject regex: a JavaScript-flavor regular expression. The message fires only if the subject matches.

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Rotating the address

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Workflow input

{
  "provider": "resend",
  "emailId": "4ef9a417-02e9-4d39-ad75-9aa401bb7d2a",
  "messageId": "<CAOg7P2Vy@mail.example.com>",
  "from": "Alice Chen <alice@acme.com>",
  "to": ["mh-x7k2m9qf4a3vbn8c@mailhook.spojit.com"],
  "cc": [],
  "replyTo": ["alice@acme.com"],
  "subject": "Invoice INV-2041",
  "text": "Hi, attached is this month's invoice...",
  "html": "<p>Hi, attached is...</p>",
  "truncated": false,
  "receivedAt": "2026-06-12T03:14:11.000Z",
  "attachments": [
    { "id": "att_1", "filename": "INV-2041.pdf", "contentType": "application/pdf" }
  ]
}

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Behavior notes

• Always asynchronous. The sender gets no response; there is no sync mode for mailhooks. Use a Send Email node in the workflow if you want to reply to {{ input.replyTo }}.
• Deduplicated per message. If the inbound provider retries delivery of the same message, the workflow still runs once.
• Any recipient field counts. The mailhook fires whether its address is in To, Cc, or Bcc.
• One email, many mailhooks. A single message addressed to the mailhook addresses of several workflows fires each of them independently.
• Unknown addresses are accepted silently. Mail to a rotated or deleted address is discarded without bouncing, so a leaked old address reveals nothing about whether it’s still live.

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Tips

• Use one mailhook per source. Separate addresses for “vendor A invoices” and “vendor B invoices” cost nothing and keep filters simple, and you can rotate one without disturbing the other.
• Pair a mailhook with a forwarding rule in your mail client to mirror a slice of a real inbox into a workflow without connecting the mailbox at all.
• Prefer the subject regex over a broad allowlist when the same sender emails you for multiple reasons.
• For testing, email the address from your own account and watch the run appear in Monitoring.