Price Monitor

Monitor website prices, inventory, and content changes using browser automation. Use when tracking e-commerce prices, competitor monitoring, stock alerts, or any web content change detection. Supports scheduled checks, price history logging, and alert notifications.

Overview

Automated price and content monitoring skill using agent-browser. Tracks price changes, stock availability, and content updates on any website with configurable alerts and history logging.

Quick Start

bash

# Monitor a product price
agent-browser open "https://example.com/product/123"
agent-browser snapshot -i
agent-browser get text @e1  # Get price element

Core Workflows

1. Single Product Price Check

Use case: Check current price of a specific product

bash

# Navigate to product page
agent-browser open "<product-url>"

# Get page snapshot to find price element
agent-browser snapshot -i

# Extract price (use appropriate ref from snapshot)
agent-browser get text @e1

# Optional: Save to history log
echo "$(date), $(price)" >> price-history.csv

2. Multi-Product Monitoring

Use case: Track prices across multiple products/competitors

Create a products.csv with URLs and price selectors:

csv

url,selector,name
https://site-a.com/product1,.price-tag,Product A
https://site-b.com/item2,#price,Product B

Run monitoring script:

bash

python scripts/monitor_prices.py products.csv

3. Stock/Inventory Alerts

Use case: Get notified when out-of-stock items become available

bash

agent-browser open "<product-url>"
agent-browser snapshot -i
agent-browser get text @e1  # Check for "In Stock" or "Out of Stock"

4. Price History Tracking

Use case: Build historical price data for analysis

Script automatically logs:

• Timestamp
• Product name/URL
• Current price
• Stock status

Output: price-history.csv or JSON format

Scripts

monitor_prices.py

Main monitoring script that:

• Reads product list from CSV
• Navigates to each URL
• Extracts price using CSS selector
• Logs results with timestamp
• Detects price changes
• Optional: Send alerts on significant changes

Usage:

bash

python scripts/monitor_prices.py products.csv [--alert-threshold 10]

Arguments:

• products.csv - Product list with URLs and selectors
• --alert-threshold - Percentage change to trigger alert (default: 10%)

Configuration

Product List Format (CSV)

csv

url,selector,name,min_price,max_price
https://amazon.com/dp/B08N5WRWNW,.a-price-whole,Sony Headphones,50,150
https://bestbuy.com/site/12345,.priceView-hero-price,TV,200,500

Alert Options

• Email alerts - Configure SMTP settings
• Discord webhook - Post to Discord channel
• File logging - Append to CSV/JSON
• Console output - Print changes to terminal

Best Practices

1. Rate limiting - Add delays between requests (30s+ recommended)
2. Error handling - Handle page load failures gracefully
3. Selector stability - Use stable CSS selectors, avoid dynamic classes
4. Headless mode - Run browser in headless mode for automation
5. Schedule wisely - Check prices during business hours for accuracy

Example: Daily Price Check Cron

bash

# Run every day at 9 AM
0 9 * * * cd /path/to/skill && python scripts/monitor_prices.py products.csv

Troubleshooting

• Element not found: Re-run snapshot to get updated refs
• Price format issues: Adjust selector or parse with regex
• Page load timeout: Increase timeout or add wait condition
• Blocked by site: Add delays, rotate user agents, or use residential proxy