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

🚀 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 ap-manager@example.com 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

kumar@smartflowcraft.com

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