{"product_id":"n8n-invoice-drafts-from-chat-or-forms-w-claude-google-workspace","title":"n8n Invoice Drafts from Chat or Forms w\/ Claude \u0026 Google Workspace","description":"\u003ch3\u003eGenerate polished invoice drafts in minutes—automatically from Chat or Forms (Claude + Google Workspace)\u003c\/h3\u003e\n\u003cp\u003eThis n8n workflow turns an invoice request from \u003cb\u003en8n Form\u003c\/b\u003e or \u003cb\u003eGoogle Chat\u003c\/b\u003e into a \u003cb\u003ePDF invoice\u003c\/b\u003e using a \u003cb\u003eGoogle Docs template\u003c\/b\u003e, then creates a \u003cb\u003eGmail draft\u003c\/b\u003e with the PDF attached. It also logs each invoice in \u003cb\u003eGoogle Sheets\u003c\/b\u003e for traceability.\u003c\/p\u003e\n\n\u003ch3\u003eWhat this workflow does\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cb\u003eReceives an invoice request\u003c\/b\u003e via an n8n Form submission or a Google Chat webhook event.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cb\u003eValidates Google Chat access\u003c\/b\u003e by checking the sender email against an allowlist—responding with help text or an access error if unauthorized.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cb\u003eExtracts customer and month\u003c\/b\u003e by loading the \u003cb\u003eCustomers\u003c\/b\u003e, \u003cb\u003eItems\u003c\/b\u003e, and \u003cb\u003eInvoices\u003c\/b\u003e tabs from Google Sheets and sending the customer list plus the request text to \u003cb\u003eAnthropic Claude\u003c\/b\u003e.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cb\u003eVerifies extracted details\u003c\/b\u003e, then calculates invoice lines, totals, tax, due date, and an invoice number using the Google Sheets data.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cb\u003ePrevents bad outputs\u003c\/b\u003e by stopping with an error if required data is missing, amounts are invalid, there are too many lines, or the invoice number already exists (unless marked void).\u003c\/li\u003e\n  \u003cli\u003e\n\u003cb\u003eCreates the invoice PDF\u003c\/b\u003e by copying a Google Docs template in Google Drive, replacing placeholders via the Google Docs API, exporting to PDF, and preparing the final document.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cb\u003eDrafts the email\u003c\/b\u003e in \u003cb\u003eGmail\u003c\/b\u003e to the customer with the PDF attached, and returns a form completion page or a Google Chat reply including the document link.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cb\u003eLogs the invoice\u003c\/b\u003e by appending a row to the \u003cb\u003eInvoices\u003c\/b\u003e tab in Google Sheets.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eUse cases\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003eSaaS and service teams generating recurring invoices from customer requests without manual document edits.\u003c\/li\u003e\n  \u003cli\u003eOperations workflows where staff message requests in Google Chat and receive an invoice link and email draft automatically.\u003c\/li\u003e\n  \u003cli\u003eAutomated invoicing for businesses that maintain customer, item, and invoice numbering in Google Sheets.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eTechnical details\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003eIntegrations include \u003cb\u003eGoogle Workspace\u003c\/b\u003e (Google Sheets, Google Drive, Google Docs, Gmail) and \u003cb\u003eAnthropic Claude\u003c\/b\u003e.\u003c\/li\u003e\n  \u003cli\u003en8n nodes\/features referenced: \u003cb\u003eif\u003c\/b\u003e, \u003cb\u003eset\u003c\/b\u003e, \u003cb\u003ecode\u003c\/b\u003e, \u003cb\u003eform\u003c\/b\u003e, \u003cb\u003egmail\u003c\/b\u003e, \u003cb\u003ewebhook\u003c\/b\u003e.\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"N8N Commerce","offers":[{"title":"Default Title","offer_id":46248868511923,"sku":"N8N-21254","price":19.99,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0749\/6279\/6723\/files\/bmehL1FesttwFzYsyyRWG_sTN4JZWk.png?v=1792487066","url":"https:\/\/buyflowscripts.com\/products\/n8n-invoice-drafts-from-chat-or-forms-w-claude-google-workspace","provider":"N8N Commerce","version":"1.0","type":"link"}