{"uid":"cap_xJikY09Jp58Xw4Qn03bxG","slug":"url-change-watch-60af402a","name":"URL Change Watch","description":"Fetch a public https URL, compute SHA-256 of the response body, and report whether it changed vs a prior sha256/etag ($0.01 USDC via x402). Sticky: store sha256 and call again later. Optional previous_sha256, previous_etag, include_body_if_changed. https only — http, file, data, localhost, and private IPs rejected. Caps: 1 MB body, ~10s timeout, max 5 redirects. Returns JSON { url, final_url, content_type, byte_length, sha256, etag?, last_modified?, changed, warnings, body_preview? }.","url":"https://well-009-url-change-watch.rainmaker-wells.workers.dev/mcp?utm_source=zero.xyz#url-change-check#url-change-check","method":"POST","headers":{},"bodySchema":null,"responseSchema":null,"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.01","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"registry","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":"$0.01/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.01","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.01","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_uKJJrEfRjFKvJZt2tSybk","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.01","costPer":"request","priority":0,"asset":null,"unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Fetches a public HTTPS URL, computes SHA-256 of the response body, and reports whether the content has changed compared to a previously recorded hash or ETag.","exampleAgentPrompt":"Check if https://example.com/data.json has changed since my last check — compare it against my stored SHA-256 of abc123def456 and return the new hash along with the page body if it changed.","exampleUseCases":[{"title":"Monitor competitor pricing page","prompt":"Check if https://competitor.com/pricing has changed since my last check — I stored the SHA-256 as 9f86d081884c7d659a2feaa0c55ad015a3bf4f1b2b0b822cd15d6c15b0f00a8b, and include the body if anything is different."},{"title":"Track government regulation updates","prompt":"Has the content at https://regulations.gov/document/some-rule changed since yesterday? My previous SHA-256 was 3fdba35f04dc8c462986c992bcf875546257113072a909c162f7e470e581e278 — let me know if anything is different."},{"title":"Verify static asset integrity","prompt":"Fetch https://cdn.myapp.com/bundle.js and tell me its current SHA-256 hash — I want to compare it to 7de9f8ba2f56e2b20d40daa5c4f7a9f3d2e6b8c1 to confirm the file hasn't been tampered with."}],"resultDescription":"A JSON object containing: the requested URL, the final URL after redirects, content_type, byte_length, sha256 hash of the response body, optional ETag and last_modified headers, a boolean 'changed' flag indicating whether content differs from the supplied previous_sha256 or previous_etag, any warnings (e.g. redirect notices, size limits), and an optional body_preview if include_body_if_changed was set.","failureModes":["Non-HTTPS URLs (http, file, data, localhost, private IPs) are rejected with an error","Response bodies exceeding 1 MB are truncated or rejected","Target URL takes longer than ~10 seconds to respond — timeout error","More than 5 redirects causes a redirect-limit error","Target server returns a non-200 status — reflected in warnings or error","Network errors reaching the target URL"],"whenToPreferThis":"Use this endpoint when you need lightweight, hash-based change detection for a public HTTPS URL without setting up a persistent webhook or crawler. It is ideal for polling-based monitoring workflows where an agent periodically checks a URL and compares the current SHA-256 or ETag to a previously stored value. Prefer it over full scraping tools when you only need to know if content changed (not what changed), or when you want to verify the integrity of a static asset. Not suitable for private/internal URLs, URLs requiring authentication, or bodies larger than 1 MB.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-22T12:30:29.077Z","isFirstParty":false,"canonicalSlug":"url-change-watch-60af402a"}