Extract invoice data from Slack PDFs to Google Sheets with GPT-4o
Ready for 3.0Ready for 3.0. This template uses no nodes that n8n 3.0 removes. No removed nodes, versions or helpers found. Static check, last run 2026-10-19.
What this workflow does
This AI workflow has 8 nodes and runs on Slack events. Along the way it connects Google Sheets, Slack and OpenAI Chat Model.
How it runs
Trigger: On Slack events.
- Fetch the pdf (HTTP Request): calls an HTTP API
- Extract information from pdf (Extract from File): extracts data from a file (pdf)
- Extract invoice information (AI Agent): runs an AI agent, with model: AI model; output parser: Structure Output
- Append row in sheet (Google Sheets): append
- Send a message (Slack): uses Slack
Services it uses
Before you upgrade to n8n 3.0
Nothing in this workflow is removed in n8n 3.0, so it should import and run after the upgrade.
- Still check Slack Trigger requires a signing secret on the Slack API credential (Receive invoice pdf).
Nodes used (8)
- Google Sheets
n8n-nodes-base.googleSheets - Slack
n8n-nodes-base.slack - Structured Output Parser
@n8n/n8n-nodes-langchain.outputParserStructured - OpenAI Chat Model
@n8n/n8n-nodes-langchain.lmChatOpenAi - Slack Trigger
n8n-nodes-base.slackTrigger - HTTP Request
n8n-nodes-base.httpRequest - Extract from File
n8n-nodes-base.extractFromFile - AI Agent
@n8n/n8n-nodes-langchain.agent
From the author
Managing invoices manually can be time-consuming and error-prone. This workflow automates the process by extracting key invoice details from PDFs shared in Slack, structuring the information with AI, saving it to Google Sheets, and sending a confirmation back…