Build a receipt and invoice capture pipeline for agent purchase records

Steps

1. At checkout completion, the agent should capture: the confirmation page HTML/screenshot, the order ID, merchant name, itemized amounts, and any receipt download links before navigating away — these are often unavailable after the session ends.
2. Monitor the principal's email inbox (with explicit authorization) for receipt emails from merchant domains matching recent agent purchases; parse the email for structured fields (order ID, amount, merchant, date) and attach to the matching purchase record.
3. Store receipt documents (PDF, HTML snapshot, or structured JSON) in an immutable object store with the purchase record ID as the object key prefix; retain for the same period as financial records.
4. Validate captured receipts against the corresponding transaction in your audit log: amount, merchant, and date must match within tolerance; flag mismatches for human review.
5. For recurring purchases, detect when a receipt is missing (expected based on subscription cadence but not received) and trigger a retrieval attempt via the merchant's portal or a follow-up email request.
6. Expose a receipt search interface keyed by merchant, date range, and amount to support expense reporting and audit queries.