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Change Detection

Learn how Diffy detects and classifies changes.

How It Works

Diffy uses a multi-step process to detect changes:

  1. Crawling - Periodically fetch page content
  2. Extraction - Parse relevant content (ignoring ads, navigation, etc.)
  3. Comparison - Compare with previous snapshot
  4. Classification - Determine change type and severity

Change Types

TypeDescriptionExample
Price ChangePricing amounts modified"$99/mo" → "$129/mo"
Feature AddedNew capability listedNew feature in comparison table
Feature RemovedCapability removedFeature no longer listed
Terms UpdateLegal/policy changesUpdated privacy policy
Content ChangeGeneral text modificationsUpdated product description

Severity Classification

Changes are automatically classified by severity:

Critical

  • Pricing increases > 20%
  • Terms of service changes
  • Feature deprecation notices

High

  • Any pricing change
  • New major features
  • Significant content updates

Medium

  • Minor feature updates
  • FAQ changes
  • Documentation updates

Low

  • Typo fixes
  • Minor rewording
  • Style changes

Noise Reduction

Diffy filters out noise to focus on meaningful changes:

  • Ignores dynamic content (timestamps, session IDs)
  • Filters navigation and footer changes
  • Excludes ads and promotional banners
  • Normalizes whitespace differences