{"uid":"cap_UVp4zH7hs1b9-ZKDdHgnO","slug":"does-site-use-clerk-daa57f79","name":"does-site-use-clerk","description":"Does a website use Clerk? Fetches the page (homepage for a bare domain) and matches Clerk's fingerprints in the HTML and response headers, returning yes/no with the evidence snippet and the category (auth). Technographics for sales, competitor research and migration planning, one technology per call. $0.01 per check.","url":"https://site.intel.rallylive.ca/site/uses/clerk?utm_source=zero.xyz","method":"GET","headers":{},"bodySchema":{"type":"object","$schema":"https://json-schema.org/draft/2020-12/schema","required":["input"],"properties":{"input":{"type":"object","required":["type","method"],"properties":{"type":{"type":"string","const":"http"},"method":{"enum":["GET"],"type":"string"},"queryParams":{"type":"object","properties":{}}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object"}}}}},"responseSchema":null,"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.01","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":"$0.01/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_BYFCw-8JWfjUjoNRX-ajm","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.01","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Detects whether a given website uses the Clerk authentication platform by fingerprinting its homepage HTML and response headers","exampleAgentPrompt":"Can you check if stripe.com uses Clerk for authentication? I want to know if they're a Clerk customer before I reach out about a migration.","exampleUseCases":[{"title":"Sales prospecting for Clerk competitors","prompt":"I'm building a list of companies to pitch our auth migration tool to — can you check if notion.so uses Clerk?"},{"title":"Competitor tech stack research","prompt":"I want to know if my competitor linear.app is running Clerk for their login system — can you detect that from their homepage?"},{"title":"Migration planning for existing Clerk users","prompt":"We're building a list of Clerk customers to target for our identity platform migration service — can you tell me if vercel.com is currently using Clerk?"}],"resultDescription":"Returns a yes/no boolean indicating whether the site uses Clerk, along with an evidence snippet (the matching HTML or header fragment that triggered the fingerprint) and the technology category label (auth). Priced at $0.01 per call.","failureModes":["Domain is unreachable or returns a non-200 response — result may be indeterminate","Clerk fingerprints are obfuscated or loaded via deferred JavaScript — may return false negative","Bare domain redirects to a subdomain that uses Clerk — may miss detection if homepage is not the auth entry point","Rate limiting or bot blocking on target domain — fetch may fail"],"whenToPreferThis":"Choose this endpoint when you need a fast, cheap, single-domain technographic check specifically for Clerk authentication. It is purpose-built for sales prospecting, competitor stack analysis, and migration targeting workflows where you need yes/no Clerk detection with evidence. Use bulk sibling endpoints when checking multiple domains. Prefer this over generic web scraping when the sole question is 'does this site use Clerk?'","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-11T00:47:10.873Z","isFirstParty":false,"canonicalSlug":"does-site-use-clerk-daa57f79"}