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+
+## PO email intake
+
+Purchase orders that arrive by email in `ai@megainfra.co.za` are filed into the dashboard by the
+n8n workflow **MEGA - PO Email Intake (Microsoft Outlook)** (`gpKjNsXoqNUzsMb4`).
+
+Two rules that must not be dropped:
+
+1. **Check for a duplicate before filing anything.** Two checks: the same document at the same
+   site (file hash + site → archive the mail, file nothing), and the PO number already in the
+   system (read from the attachment filename or subject, e.g. `MEGCPO9524.pdf` → tag
+   `PO Duplicate` and leave it for a human). The app re-checks both after OCR in
+   `/api/purchase-orders/process-batch` (`po_number_conflict`).
+2. **Move processed mail out of the inbox.** A successful filing is tagged `PO Ingested` and
+   moved to Archive; `PO Duplicate` and `PO Needs Review` stay in the inbox for review and are
+   skipped on later runs.
+
+Full runbook and workflow source: `docs/n8n/po-email-intake.md` and
+`docs/n8n/po-email-intake.workflow.js`.