Classify invoices and route them to Google Drive with easybits and Slack

Description

What This Workflow Does
Upload a document (PDF, PNG, JPEG) via a web form and let easybits Extractor classify it into one of your defined categories. Based on the classification result and a confidence score, the document is automatically sorted into the correct Google Drive folder. Low-confidence or unrecognized documents are flagged for manual review via Slack.

How It Works
User uploads a file through the hosted web form
The binary file is converted to base64 and sent to easybits
easybits returns a document_type and confidence_score
The classification result is merged with the original file binary
If confidence > 0.5 → routed to the matching Google Drive folder
If confidence ≤ 0.5 or no category match → uploaded to Needs Review folder + Slack alert

Supported categories:
medical_invoice · restaurant_invoice · hotel_invoice · trades_invoice · telecom_invoice

Setup Guide

1. Set Up Your easybits Extractor Pipeline
Go to extractor.easybits.tech and create a new pipeline
Add two fields to the mapping: document_class and confidence_score
In each field's description, paste the corresponding classification or confidence prompt that tells the model how to analyze the document
The classification prompt should return exactly one category label – or null if uncertain
The confidence prompt should return a decimal number between 0.0 and 1.0
Save & test the pipeline, then copy your Pipeline ID and API Key

2. Set Up Google Drive
Create a folder in Google Drive for each category: Medical, Restaurant, Hotel, Trades, Telecom, and Needs Review
In n8n, go to Settings → Credentials and create a Google Drive OAuth2 credential
This requires a Client ID and Client Secret from the Google Cloud Console (APIs & Services → Credentials → OAuth 2.0 Client ID)
Make sure the Google Drive API is enabled in your Google Cloud project
Open each of the 6 Google Drive upload nodes in this workflow and select the correct target folder

3. Set Up Slack
In n8n, go to Settings → Credentials and create a Slack API credential
You'll need a Slack Bot Token – create a Slack App at api.slack.com/apps, add the chat:write scope, and install it to your workspace
Create a channel for review notifications (e.g. #n8n-invoice-review)
Invite the bot to that channel
Open the Review Message node and select the correct channel

4. Connect the easybits Node
Open the easybits Extractor (Classification) node
Replace the pipeline URL with your own: https://extractor.easybits.tech/api/pipelines/YOUR_PIPELINE_ID
Create a Bearer Auth credential using your easybits API Key and assign it to the node

5. Activate & Test
Click Active in the top-right corner of n8n
Open the form URL and upload a test document
Check the execution log to verify the classification result
Confirm the file lands in the correct Google Drive folder
Test with an unrecognized document to verify the Slack notification fires