Build an Invoice Approval Agent That Drafts, But Never Pays

Description and use

An automated agent processes invoices, validates them against policies, and creates a review object that requires human approval, but never triggers payment.

Problem

Automate invoice processing while ensuring no automatic payments are made, requiring human review for approval.

Outcome

The agent reliably extracts invoice data, applies policy checks, and produces a review object that requires human approval before payment, eliminating accidental automated payments.

Workflow

• 1. Install EngageLab Email CLI and set up a read‑only test mailbox. 2. Poll inbound emails via engagelab-email-cli emails receiving listen. 3. Persist cursor after committing review record. 4. For each event, fetch the full thread with engagelab-email-cli threads messages. 5. Extract invoice fields (amount, vendor, PO, attachment name). 6. Run evaluateInvoice to compare against policy (allowlisted vendors, expected PO, threshold, PDF attachment). 7. Generate a review object with recommendation (approve_after_human_review or needs_more_review) and reasons. 8. Store or forward the review object for human finance review; no payment is initiated automatically.

Evidence

The agent should not treat the PDF, the sender address, or a sentence in the email as authorization to pay.

Source

The safe shape is: inbound invoice -> complete thread -> validated extraction -> policy checks -> review object X no automatic payment

Source