Route difficult negative invoice lines to Claude while code handles predictable entries and matching
An automation builder describes processing Japanese Google Ads invoices with n8n, code and Claude, then sending matched records through Sheets to a client's internal API.
Evidence: The author reports this. We have not checked it beyond reading the source.
The business problem
An advertising agency was missing negative invoice lines during slow manual entry.
What was tried
Process predictable positive lines with code and send complex negative lines to Claude 3.5 Sonnet for extraction. Fuzzy-match project names against internal records, format data in Google Sheets and submit rows through HTTP calls to the client's Board API. In comments, the author describes Telegram notifications for a person to inspect invoices in Gmail, especially negative-only documents.
What was reported (positive)
The builder claims processing takes minutes rather than hours, with near-perfect accuracy. No sample size or measured error rate is supplied.
Limitations
The post and comments differ on the parser's role. The headline's $2,000 monthly figure is described as value, not established revenue. Only Google invoices were supported at the time.
What you need
n8n, Claude, Google Sheets, access to the client's API and a reviewer using Telegram/Gmail.
Sources
- u/gleb_ai_automation on r/n8n ↗ Community discussion, publication date unknown
Source published: unknown. Last reviewed here: October 19, 2026. Spot a mistake? Tell us.
Tools in this workflow
- Claude: Extracts difficult negative linesTry Claude
- Google Sheets: Formats extracted recordsTry Google Sheets
- n8n: Coordinates invoice processingTry n8n
- Telegram: Alerts a human reviewerTry Telegram
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