How to Build a Price Monitoring Agent with Pydantic AI and ZenRows

Short summary

This tutorial demonstrates building a price monitoring agent using ZenRows for retrieval and Pydantic AI for structured extraction. It addresses two silent failure modes: retrieval failures where protected sites return block pages instead of product data, and extraction failures where LLM output drifts between data types across runs. The guide walks through a two-step pipeline from single-page scraping to multi-site monitoring across Amazon and Walmart.

• •Two silent failure modes in price monitoring: retrieval blocks and LLM extraction drift
• •ZenRows handles anti-bot retrieval with 99.93% success rate on protected sites
• •Pydantic AI validates LLM output against a schema to prevent downstream database write failures

Generated with AI, which can make mistakes.