{"uid":"cap_WKmyXPrXwDttloKIE-U11","slug":"agentwork-web-evidence-change-detection-46142c90","name":"AgentWork Web Evidence - Change Detection","description":"Web reads and change checks: $0.005 on Base, $0.01 on Algorand; digital PDF-to-text $0.01. Structured JSON, hashes and x402 USDC. No API key.","url":"https://api.agentwork.run/v1/web/changes","method":"POST","headers":{},"bodySchema":{"type":"object","properties":{"url":{"type":"string","format":"uri","maxLength":2048,"description":"Public HTTP/HTTPS URL; ports 80/443 and public IPv4 resolution only"},"max_chars":{"type":"integer","default":20000,"maximum":60000,"minimum":1000,"description":"Maximum returned characters; keep identical between comparisons"},"previous_text":{"type":"string","maxLength":60000,"description":"Exact text from the prior read, for line additions/removals"},"previous_sha256":{"type":"string","pattern":"^[a-fA-F0-9]{64}$","description":"Prior text_sha256; provides a compact change check without line diff"}}},"responseSchema":{"type":"json","example":{"ok":true,"url":"https://example.com/","text":"Example Domain\nNew line","comparison":{"added":["New line"],"changed":true,"removed":["Old line"]},"fetched_at":"2026-09-08T00:00:00Z"}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.005","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":"$0.005/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.005","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.005","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_c5HkO9lOYvBpKCF3uL21c","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.005","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Checks whether a public webpage has changed since a previous read, returning either a compact changed/unchanged flag or a line-level diff of added and removed content.","exampleAgentPrompt":"Check whether the pricing page at https://example.com/pricing has changed since my last read — here's the SHA-256 hash from before: 3a5b9c... — just tell me if it changed or not, no need for a full diff.","exampleUseCases":[{"title":"SaaS pricing page tracker","prompt":"Check if the pricing page at https://stripe.com/pricing has changed since my last check — I have the SHA-256 hash from yesterday's read: e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855. Just let me know if it changed."},{"title":"Policy update monitoring for compliance","prompt":"I need to know what specifically changed on https://openai.com/policies/usage-policies since last week. Here's the full text from my previous read so you can show me exactly which lines were added or removed."},{"title":"Documentation change alerting for developer agents","prompt":"Has the content at https://docs.anthropic.com/en/api/getting-started changed since I last fetched it? Use this SHA-256 to do a quick changed/unchanged check: a948904f2f0f479b8f936099f6e4b4d94a3d9ee3c8a4e2e5e9c8b7f6d5c4b3a2."}],"resultDescription":"Returns a JSON object with ok status, the current page URL, extracted plain text (up to max_chars), a fetch timestamp, and a comparison object containing a boolean 'changed' flag plus arrays of 'added' and 'removed' lines (populated only when previous_text was supplied). When only a SHA-256 hash is provided, the comparison includes 'changed' but no line diff.","failureModes":["Non-public or private URLs return an error — only publicly accessible HTTP/HTTPS pages on ports 80/443 are supported","JavaScript-rendered content will not be captured — only static HTML/text is fetched","URLs resolving to non-public IPv4 addresses (e.g. internal IPs) are rejected","If max_chars differs between calls, comparisons may be unreliable — callers must keep this value consistent","Malformed or incorrect previous_sha256 (not a valid 64-character hex string) will be rejected","Payment failure over x402 protocol results in the check not being performed","Pages exceeding 60,000 characters after truncation may produce incomplete diffs"],"whenToPreferThis":"Choose this endpoint when you need a lightweight, stateless change-detection check for a specific public webpage without storing history server-side — ideal for recurring monitoring loops where the caller maintains the baseline (SHA-256 or prior text). Prefer the SHA-256 mode for bandwidth efficiency when you only need a changed/unchanged signal, and the previous_text mode when you need a precise line-level diff. This is better than a full page-fetch endpoint when the primary goal is detecting modifications rather than ingesting new content.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-15T12:34:11.693Z","isFirstParty":false}