Colombian Invoices Processing

This workflow is ideal for:

• Small Business Owners who deal with electronic invoices and need to automate the processing of invoices received via email.
• Freelancers who want to streamline their invoicing process and keep track of their expenses efficiently.
• Accountants looking to save time on data entry and ensure accurate record-keeping of invoices.
• Individuals who want to manage personal invoices without manual effort.

This workflow addresses the challenges of:

• Manual Invoice Processing: Automates the extraction and organization of invoices, reducing the time spent on manual entry.
• Data Accuracy: Ensures that the extracted data is validated and accurate, minimizing errors in financial records.
• Storage and Organization: Automatically uploads invoices to Google Drive and keeps a structured record in Google Sheets, making retrieval easy and organized.
• Compliance: Follows DIAN requirements for electronic invoices in Colombia, ensuring that users remain compliant with local regulations.

1. Email Trigger: Checks Gmail every 30 minutes for emails with .zip attachments containing invoices.
2. ZIP File Handling: Extracts files from the ZIP and filters for PDF and XML formats for further processing.
3. Data Extraction: Uses LangChain Agent + OpenAI (GPT-4o-mini) to extract key invoice information:
   • Document Type (Invoice / Credit Note)
   • Invoice Number
   • Issue Date (format: YYYY-MM-DD)
   • Issuer's NIT and Receiver's NIT (without verification digit)
   • Issuer's Business Name
   • Subtotal, VAT, Total Amount
   • CUFE
   • Purchase Summary (max 20 words, grammatically formatted)
4. Validation: Confirms that Total = Subtotal + VAT using a calculator node to ensure accuracy.
5. Storage: Uploads the original PDF to Google Drive with the new name format: YYYY-MM-DD-NUMERO_FACTURA.pdf and updates Google Sheets with invoice details, using a unique key to prevent duplication.