{"uid":"cap_LqlBlevLiqMF8Tljkz77A","slug":"hmac-sha1-hex-signer-76c868ac","name":"HMAC-SHA1 Hex Signer","description":"Call when an agent needs an HMAC-sha1 of text with a caller-supplied key, encoded as hex. Exact $0.002 USDC. Prefer unpaid POST /v1/sandbox/hmac-sha1-hex first.","url":"https://agentshelf.syntexa.ch/v1/hmac-sha1-hex?utm_source=zero.xyz","method":"POST","headers":{},"bodySchema":{"type":"object","properties":{"key":{"type":"string","examples":["secret"],"maxLength":512,"minLength":1,"description":"HMAC secret. Required on HMAC SKUs. Omit it for plain digests and checksums. The key is not stored."},"text":{"type":"string","examples":["hello"],"maxLength":100000,"minLength":1,"description":"Message to digest. For raw-hex SKUs this is hex bytes; for utf16 or latin1 SKUs it is decoded with that encoding. Otherwise it is UTF-8 text."}}},"responseSchema":null,"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.002","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":"$0.002/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.002","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.002","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_dP3RlfWmp0-3rb-Inzvp1","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.002","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Computes an HMAC-SHA1 of a given text using a caller-supplied key and returns the result as a lowercase hex string.","exampleAgentPrompt":"Compute an HMAC-SHA1 hex signature for the text 'order_id=9821&amount=49.99' using the secret key 'mysecretkey123'.","exampleUseCases":[{"title":"Webhook signature generation","prompt":"I need to sign an outgoing webhook payload 'user.created:{id:42}' with the shared secret 'wh_secret_abc' using HMAC-SHA1 — give me the hex digest to put in the X-Signature header."},{"title":"API request authentication","prompt":"Can you generate an HMAC-SHA1 hex signature for the string 'GET\\n/api/orders\\n1716220800' using the key 'api_key_xyz987' so I can authenticate my API request?"},{"title":"Message integrity verification","prompt":"Compute the HMAC-SHA1 hex of the message 'invoice:2024-001,total:500.00' using the secret 'verify_key_qwerty' — I need to check whether the digest matches what the other party sent."}],"resultDescription":"Returns a hex-encoded HMAC-SHA1 digest string computed from the provided text and key. The output is a 40-character lowercase hexadecimal string representing the 160-bit SHA1 HMAC.","failureModes":["Empty or missing key returns a validation error","Empty or missing text returns a validation error","Key exceeding 512 characters is rejected","Text exceeding 100,000 characters is rejected","Payment of exactly $0.002 USDC required; missing or insufficient payment returns 402"],"whenToPreferThis":"Use this endpoint when your agent needs a serverless, pay-per-call HMAC-SHA1 hex computation without running local crypto libraries — particularly in constrained or sandboxed environments. Prefer the free sandbox endpoint (/v1/sandbox/hmac-sha1-hex) for testing. Choose this paid endpoint for production use where reliability and uptime guarantees matter.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-01T06:47:47.875Z","isFirstParty":false,"canonicalSlug":"hmac-sha1-hex-signer-76c868ac"}