{"uid":"cap_rl2s3poKlxD5GWNB57uJ2","slug":"free-asset-radar-x402-hmac-utility-3df70cd3","name":"Free Asset Radar x402 HMAC Utility","description":"Stable edge-hosted x402 utilities for autonomous agents.","url":"https://free-asset-radar-x402.besenok2018.workers.dev/api/x402/hmac?utm_source=zero.xyz","method":"GET","headers":{},"bodySchema":{"type":"object","properties":{"required":{"type":"string"},"properties":{"type":"string"}}},"responseSchema":{"type":"json","example":{"hex":"...","algo":"sha256","base64":"..."}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.0005","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":"$0.0005/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.0005","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.0005","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_HoJYeElsBwVoBHjONzqLw","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.0005","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Computes an HMAC signature (hex and base64) using SHA-256 for a given input, edge-hosted for autonomous agents via x402 micropayment.","exampleAgentPrompt":"Compute an HMAC SHA-256 signature for the message 'order:12345:confirmed' and give me both the hex and base64 output.","exampleUseCases":[{"title":"Webhook payload integrity check","prompt":"I need to verify the integrity of an incoming webhook payload — can you compute the HMAC SHA-256 signature for the body string 'event=purchase&amount=50&user=abc123' so I can compare it to the header signature?"},{"title":"API request signing for autonomous agent","prompt":"My agent needs to sign outgoing API requests — generate an HMAC SHA-256 signature in both hex and base64 for the string 'GET /resource timestamp=1718000000'."},{"title":"Message authentication token generation","prompt":"Can you create an HMAC SHA-256 authentication code for the message 'session:user42:1718100000' so I can include it as a token in a secure message?"}],"resultDescription":"Returns a JSON object containing the HMAC signature in hexadecimal ('hex'), the algorithm used ('algo', e.g. 'sha256'), and the base64-encoded signature ('base64'). All three fields are computed from the provided input payload.","failureModes":["Missing required input fields returns an error or malformed response","Invalid property types in the request body may result in a 400 error","Payment failure (insufficient USDC balance or x402 handshake error) blocks the request","Cloudflare Worker cold start or edge outage may cause transient 503 errors","Malformed JSON body may return an unparseable response"],"whenToPreferThis":"Choose this endpoint when you need a fast, edge-hosted HMAC SHA-256 computation accessible via x402 micropayment without managing your own crypto infrastructure. It is ideal for autonomous agents that need to sign or verify messages on-the-fly with minimal latency and no server setup. Prefer alternatives if you need HMAC with algorithms other than SHA-256, or if you require batch signing of many messages at once.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-18T18:45:01.822Z","isFirstParty":false,"canonicalSlug":"free-asset-radar-x402-hmac-utility-3df70cd3"}