{"uid":"cap_BQsLLKiNRIxq9K6Nr3ErV","slug":"fetchwerk-diff-content-change-detection-17a2842a","name":"fetchwerk Diff — Content Change Detection","description":"Compare a page against its last stored state, or two supplied documents, and report only the content changes.","url":"https://fetch.halowerk.com/diff","method":"POST","headers":{},"bodySchema":{"type":"object","properties":{"url":{"type":"string","format":"uri","description":"Page to fetch and compare against its last stored state."},"after":{"type":"string","description":"Later document as HTML or Markdown."},"since":{"type":"string","format":"date-time","description":"ISO timestamp. Picks the stored state at or before this moment instead of the newest one."},"before":{"type":"string","description":"Earlier document as HTML or Markdown. No network access is used."},"after_fetched_at":{"type":"string","format":"date-time","description":"Optional, echoed back for inline comparisons."},"before_fetched_at":{"type":"string","format":"date-time","description":"Optional, echoed back for inline comparisons."}}},"responseSchema":null,"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.003","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"probe","requiresHandshake":false,"reviewCount":0,"rating":{"score":"0.00","successRate":"0.00","reviews":0,"stars":null,"state":"unrated"},"availabilityStatus":"unknown","priceObserved":null,"sessionDeposit":null,"pricing":{"kind":"static","summary":"$0.003/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.003","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.003","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_b8SjiYzfVq2c8Xhr4p-T7","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.003","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Compares a web page against its last stored snapshot, or two supplied documents, and returns only the content that has changed.","exampleAgentPrompt":"Can you check what's changed on https://example.com/pricing since yesterday — compare the current version against its last stored snapshot and just show me what's different?","exampleUseCases":[{"title":"Track competitor pricing page updates","prompt":"Check https://acmecorp.com/pricing against its last stored snapshot and tell me exactly what content changed — I want to know if they've updated their plan tiers or prices."},{"title":"Verify article edits between two drafts","prompt":"Here are two versions of our blog post — the before version is the original HTML and the after version is the revised draft. Can you diff them and show me only what's changed?"},{"title":"Monitor regulatory page for new rules","prompt":"I need to know if https://sec.gov/rules/final.htm has changed since January 1st 2025 — pull the snapshot from that date and compare it to the current version, then report only the new or removed content."}],"resultDescription":"A structured diff report highlighting only the content that changed between two document versions — removed text, added text, and modified sections — along with optional echoed timestamps for provenance tracking.","failureModes":["URL not yet stored in the system (no prior snapshot available to compare against)","Invalid or unreachable URL returns a fetch error","Malformed HTML or Markdown in before/after fields causes parsing failure","'since' timestamp predates any stored snapshot, returning no baseline","Both url and before/after fields omitted, leaving the comparison target ambiguous","Rate limiting or payment failure (x402 protocol) blocks the call"],"whenToPreferThis":"Choose this endpoint when you need to detect what specifically changed on a page or between two documents — not just whether a change occurred. It is ideal for monitoring tasks (pricing pages, regulatory filings, news articles) where you want a precise delta rather than a full re-extraction. If you have two documents in hand and want an offline comparison without any network access, supply before and after directly. Prefer a full-extraction sibling endpoint if you need the complete current content rather than just the delta.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-14T12:35:35.794Z","isFirstParty":false}