Transaction Agent - Email-to-Sheets Pipeline

AI Agent (Python + LangGraph)

About

Enterprise-grade LangGraph workflow that automatically extracts financial transactions from Gmail, classifies emails using LLM, extracts structured data, and writes to Google Sheets. 7-node pipeline with error tracking.

My Role

Designed and built the complete pipeline: Gmail OAuth2, email classification, LLM-powered transaction extraction, Sheets write-back, and workflow visualization.

Core Capabilities

• 7-node workflow: fetch, classify, extract, write, mark, finalize
• Gmail API with OAuth2 for secure email access
• LLM-powered classification and structured data extraction
• Google Sheets integration for automated bookkeeping
• Error tracking and reporting at every stage

Architecture

• LangGraph state machine with TypedDict states
• OpenAI GPT-4o-mini for classification and extraction
• Gmail API + Google Sheets API integration
• Workflow graph visualization output

Tech Stack