Personal finance tracker with Telegram Bot, Google Gemini Vision, and Sheets

Personal Finance AI Agent – Telegram Bot (n8n Workflow)

A fully automated Telegram-based personal finance tracker that: - Accepts receipts as images, PDFs, or plain text - Uses Google Gemini Vision for OCR & intelligent extraction - Logs every expense into Google Sheets - Stores receipt images/PDFs in Google Drive - Answers natural-language spending questions ("How much did I spend on food last month?", "Compare this month vs last month", etc.)

Built entirely with n8n – 100% self-hostable, no-code/low-code.

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How It Works (Overview)

1. You send a message to your Telegram bot → Photo of a receipt, PDF, or just text like "Nov 10 – 2500 NGN – Uber"

2. Switch node detects the message type: - Photo → Branch 0 - Document (PDF/other) → Branch 1 - Pure text → Branch 2 (goes straight to query agent)

3. Receipt Processing Path (Images & PDFs) - Files downloaded from Telegram → uploaded to Google Drive ("Monthly receipts" folder) - Images → OCR with Gemini Vision PDFs → native PDF text extraction - Extracted text + Drive link → merged → sent to Gemini AI Agent - AI extracts: Date (YYYY-MM-DD) • Amount (NGN) • Description • Category (food, transportation, subscriptions, takeouts, entertainment, gift, electricity, repairs, other stuffs) - Clean JSON → appended to Google Sheets → friendly confirmation sent back