Send and track Slack invoice requests with Gemini, Google Sheets and Gmail
UnknownUnknown. This template uses community nodes we can't verify statically. Uses community nodes that can't be verified statically (unverified community packages are off by default in 3.0). Static check, last run 2026-10-19.
What this workflow does
This AI workflow has 25 nodes and runs on Slack events. Along the way it connects Slack, Google Sheets, Google Gemini Chat Model and Gmail and 1 more.
How it runs
Trigger: On Slack events.
- Intent Classifier Agent (AI Agent): runs an AI agent, with model: Gemini Chat Model; output parser: Parse Structured Output
- Check Intent Found (If): checks a condition and branches into true / false
- Route by Intent (Switch): routes items into 3 branches
- Read Client Bill Sheet (Google Sheets): uses Google Sheets
- Read Client Invoices Sheet (Google Sheets): uses Google Sheets
- Read Archived Invoices Sheet (Google Sheets): uses Google Sheets
- Check If Email Exists (If): checks a condition and branches into true / false
- Check Invoice Email Exists (If): checks a condition and branches into true / false
- Check Archive Email Exists (If): checks a condition and branches into true / false
- Format Invoice Data (Code): runs custom JavaScript code
…plus 11 more steps. See the full node list below.
Services it uses
Before you upgrade to n8n 3.0
We can't fully verify this one: it relies on 1 community package, and n8n 3.0 turns unverified community packages off by default (N8N_UNVERIFIED_PACKAGES_ENABLED=false).
- Check that n8n-nodes-pdfbro is verified or supports 3.0 (used in Generate PDF Invoice, Generate Invoice PDF).
- Also check Slack Trigger requires a signing secret on the Slack API credential.
Nodes used (11)
- Slack Trigger
n8n-nodes-base.slackTrigger - Switch
n8n-nodes-base.switch - Google Sheets
n8n-nodes-base.googleSheets - AI Agent
@n8n/n8n-nodes-langchain.agent - Google Gemini Chat Model
@n8n/n8n-nodes-langchain.lmChatGoogleGemini - Structured Output Parser
@n8n/n8n-nodes-langchain.outputParserStructured - If
n8n-nodes-base.if - Slack
n8n-nodes-base.slack - Pdf Bro
n8n-nodes-pdfbro.pdfBro - Gmail
n8n-nodes-base.gmail - Code
n8n-nodes-base.code
From the author
Quick overview Youtube Video: https://youtu.be/42-oHh9w9Eo This workflow listens for Slack @mentions, uses Google Gemini to classify the request and extract invoice details, then reads and updates Google Sheets, generates invoice PDFs with PdfBro, sends…