Extract & Classify Invoices & Receipts with Gmail, OpenAI and Google Drive

Who is it for?

Anyone who wants to automatically aggregate their invoices or receipts. Main beneficiaries: small business owners and freelancers.

How it works

1. Creates a folder in Google Drive for uploading invoices and receipts. Responds (Webhook response) with URL to the created folder.
2. Gets all emails with attachments from a Gmail mailbox.
3. (Optional) Filters emails, eg exclude emails sent to specific address.
4. Filters only PDF attachments.
5. Classifies all PDF attachment contents with an AI model (is it a receipt or an invoice?).
6. Uploads receipts and invoices to the created Google Drive folder and optionally sends an email with the attachments to, eg, your accountant.

Preconditions/Requirements

• Gmail and Google Drive accounts
• A Google Cloud OAuth 2.0 Client ID or a service account with Google Drive and Gmail APIs enabled
• OpenAI API account and API key

Setup steps

1. Provide credentials for the nodes: Gmail, Google Drive, OpenAI.
2. Configure parameters in the "Configure" node. Most importantly:
   • " sendInvoicesTo " for the email address where invoices/receipts should be sent.
3. It uses a Webhook node trigger. It expects a body with a schema such as:

 {
 "name": "getInvoicesAndReceiptsFromEmails",
 "description": "Finds and uploads to Google Drive all receipts and invoices from emails within a specified date range.",
 "parameters": {
 "type": "object",
 "properties": {
 "startDate": {
 "type": "string",
 "format": "date-time", 
"description": "The start date of the range to search for emails. Must be in ISO 8601 format."
 },
 "endDate": {
 "type": "string",
 "format": "date-time",
 "description": "The end date of the range to search for emails. Must be in ISO 8601 format."
 },
 "sendEmail": {
 "type": "boolean",
 "description": "Indicates whether to send an email with all receipts and invoices after processing. Must be true or false."
 }
 },
 "required": [
 "startDate",
 "endDate"
 ]
 }
 }

Example body:

 {
 "startDate": "2025-03-01T00:00:00Z",
 "endDate": "2025-04-01T00:00:00Z",
 "sendEmail": true
 }

How to use with AI chat

You can trigger the workflow with an AI chat that supports tool use, such as BrowseWiz . For setup instructions, read the blog post .