Flag duplicate and risky AP invoices with Gmail, OpenAI and Supabase

Description

🚀 How it works

Monitors your AP inbox for incoming invoices, extracts structured data
with AI, runs duplicate and vendor history checks against Supabase, then
scores each invoice for fraud risk — routing suspicious ones to Slack
and your AP team before any payment is processed.

📬 Gmail Trigger monitors your accounts payable inbox in real time
🤖 AI Agent extracts invoice number, vendor, amount, currency, dates
and line items into structured JSON — no manual data entry
🔍 Checks Supabase for duplicate invoice numbers already in the system
🏢 Checks vendor payment history — flags unknown vendors and amount
deviations above 50% from the vendor's historical average
🧠 Second AI Agent scores fraud risk: low / medium / high / critical
with specific fraud indicators and a recommended action
🚨 High/critical risk — posts a detailed Slack alert to #invoice-alerts
and emails your AP manager with a hold notice
🗄️ Logs every processed invoice to Supabase with risk score and status

🛠️ Set up steps

Estimated setup time: ~20 minutes

Gmail Trigger — connect Gmail OAuth2; point it at your AP inbox
OpenAI — connect OpenAI API credential (used by both AI Agent nodes)
Supabase — connect Supabase API credential; create two tables:
invoices (invoice_number, vendor_name, amount, status, risk_level, created_at)
and vendors (vendor_name, avg_amount, total_invoices, flagged)
Slack — connect Slack OAuth2; update the channel name #invoice-alerts
Gmail (Send) — connect Gmail OAuth2; replace [email protected]
Follow the sticky notes inside the workflow for per-node guidance

📋 Prerequisites

Gmail account receiving invoices
OpenAI API key (GPT-4o)
Supabase project with invoices and vendors tables
Slack workspace with an alerts channel
Custom Workflow Request with Personal Dashboard

[email protected]

https://www.smartflowcraft.com/contact

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