Today's Agent Skill: Inbox-to-Invoice Reconciler
What It Does
Vendor invoices land in email, get forwarded around, and quietly fall out of sync with what's actually in your accounting system. By the time someone notices, it's a duplicate payment or a missed net-30. This skill closes that gap every morning before anyone opens a spreadsheet.
How It Works
The agent scans a defined mailbox label for invoice attachments and body text, extracts vendor, invoice number, amount, currency, and due date, then compares each record against a ledger export you supply. It flags four states — matched, amount mismatch, missing from ledger, and possible duplicate — and never writes to the accounting system itself.
How to Deploy It
Drop the SKILL.md below into your agent's skills directory (for Claude Code, `~/.claude/skills/invoice-reconciler/SKILL.md`) and give the agent read access to your mail tool plus a ledger CSV path. Run it manually first against a week of known invoices to calibrate the fuzzy vendor matching before putting it on a daily schedule.
SKILL.md — Ready to Deploy
# Invoice Reconciler
## Description
Reconciles vendor invoices arriving by email against an accounting ledger export. Produces a triage report of matched, mismatched, missing, and duplicate invoices. Read-only — it never posts entries or sends payment.
## Trigger
Invoke on: `reconcile invoices`, `invoice check`, `match invoices to ledger`, `AP reconciliation`, `did we pay this invoice`. Also triggers on a daily schedule if configured, or when the user forwards an invoice and asks whether it's already been recorded.
## Input
- `mailbox_label` (required): mail label or folder holding invoices, e.g. `AP/Incoming`
- `ledger_path` (required): CSV export with columns `vendor,invoice_number,amount,currency,date_posted`
- `lookback_days` (optional, default 30)
- `amount_tolerance` (optional, default 0.01)
## Steps
1. Read the ledger CSV. Normalize vendor names: lowercase, strip punctuation, drop legal suffixes (inc, llc, ltd, gmbh).
2. Fetch messages in `mailbox_label` from the last `lookback_days`. Include PDF and image attachments.
3. For each message, extract vendor, invoice number, total amount, currency, due date. Prefer attachment text over body text when both are present.
4. If Copy the full SKILL.md and drop it into your agent's skills directory to activate this skill.