{"uid":"cap_QaSJuBU6RM4s78WqogZ0F","slug":"hmac-signature-generation-api-2f011bed","name":"HMAC Signature Generation API","description":"Global current weather, hourly forecasts, foreign-exchange rates, EVM reads, and deterministic utilities for AI agents. Pay per call with MPP or x402; no API key.","url":"https://agent-chain-kit-solana.vercel.app/v1/hmac?utm_source=zero.xyz","method":"POST","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","HEAD","DELETE"],"type":"string"},"queryParams":{"type":"object","required":["text","key"],"properties":{"key":{"type":"string"},"text":{"type":"string"},"algorithm":{"enum":["sha256","sha512","sha1"],"type":"string"}}}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object"}}}}},"responseSchema":{"type":"json","example":{"hex":"88aab3ede8d3adf94d26ab90d3bafd4a...","bytes":5,"base64":"iKqz7ejTrflNJquQ07r9Sg==","algorithm":"sha256"}},"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_1VndrwKtpUTFuVcmeDQt6","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 (SHA-256, SHA-512, or SHA-1) over arbitrary text input and returns the hex, base64, and byte-length of the digest.","exampleAgentPrompt":"Compute the HMAC-SHA256 of the message 'order-12345:1700000000' using secret key 'mySecretKey99' and give me the hex and base64 result.","exampleUseCases":[{"title":"Webhook signature verification","prompt":"Compute the HMAC-SHA256 of the raw webhook body 'user_id=42&event=purchase' with secret key 'whsec_abc123' so I can verify the signature matches what Stripe sent me."},{"title":"API request signing","prompt":"Sign the string 'GET\\n/v1/orders\\n1700000000' with key 'api-secret-xyz' using SHA-512 HMAC so I can attach the signature to my outgoing API request."},{"title":"Data integrity token generation","prompt":"Generate a SHA-1 HMAC of the text 'session-token-user-88' using key 'legacySecret' and return the hex digest so I can store it as a tamper-check token."}],"resultDescription":"Returns a JSON object containing the HMAC digest in hex string format, base64 string format, the byte length of the digest, and the algorithm that was applied (e.g. sha256, sha512, sha1).","failureModes":["Missing required 'text' or 'key' query parameters returns a validation error","Invalid algorithm value (not sha256, sha512, or sha1) causes rejection","Using an HTTP method other than GET/HEAD/DELETE is rejected by the schema","Payment failure via x402/MPP results in 402 response and no computation","Overly long input strings may result in timeout or truncation"],"whenToPreferThis":"Choose this endpoint when you need a quick, deterministic, pay-per-call HMAC digest without setting up your own crypto library or managing API keys. It is ideal for AI agents needing to sign messages, validate webhook payloads, or produce integrity tokens on the fly using SHA-256, SHA-512, or SHA-1, and where paying micro-amounts per call (via x402 or MPP) is acceptable.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-09T18:50:38.833Z","isFirstParty":false,"canonicalSlug":"hmac-signature-generation-api-2f011bed"}