Auto-log every emailed invoice into a sheet

Goal: Never type an invoice into a spreadsheet again at tax time.
Setup: agents used in source: n8n; tools/MCPs stated: Gmail, Google Sheets, Telegram.
Steps:
1. Point the workflow at one billing@ address and forward invoices from other addresses there.
2. Watch Gmail for unread emails with attachments and filter out junk files.
3. Classify “is this an invoice?” and extract the fields in the same call.
4. Look the invoice number up in the sheet before appending, so re-sends never create duplicates.
5. Append new invoices to Google Sheets and send a Telegram alert for each.
Rules: ask me before anything irreversible (sending, posting, paying, deleting); don’t invent data, results or tools I haven’t given you; tell me what you couldn’t verify.
Based on: /u/easybits_ai — https://www.reddit.com/r/n8n/comments/1wuxey9/tax_season_is_coming_the_n8n_workflow_i_built_to/

Steps are from the source. Includes a “Based on” credit line.