{"uid":"cap_Nkg8ow2cdD0T10NUxYWEy","slug":"hmac-md5-hex-digest-agentshelf-syntexa-ch-d957a80d","name":"HMAC-MD5 Hex Digest (agentshelf.syntexa.ch)","description":"Call when an agent needs an HMAC-md5 of text with a caller-supplied key, encoded as hex. Exact $0.009 USDC. Prefer unpaid POST /v1/sandbox/hmac-md5-hex first.","url":"https://agentshelf.syntexa.ch/v1/hmac-md5-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":"0.009","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":"$0.009/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.009","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.009","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_PpPn6PBb1eu1xKj8gEozc","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.009","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Computes an HMAC-MD5 authentication code over supplied text using a caller-provided secret key, returning the result as a lowercase hexadecimal string.","exampleAgentPrompt":"Calculate the HMAC-MD5 hex digest of the text 'Hello, World!' using the secret key 'mysecretkey123'.","exampleUseCases":[{"title":"Webhook signature verification","prompt":"I need to compute the HMAC-MD5 hex signature of this webhook body — the text is '{\"event\":\"payment.complete\",\"amount\":100}' and the shared secret is 'wh_secret_abc789'. What's the hex digest?"},{"title":"API request authentication","prompt":"Generate an HMAC-MD5 hex code for the string 'GET /api/orders/42 timestamp=1716300000' using the key 'api_signing_key_xyz' so I can put it in my request auth header."},{"title":"Data integrity tagging","prompt":"I want to tag this log entry 'user_id=55 action=delete record=8821' with an HMAC-MD5 fingerprint using the key 'log_secret_key' — give me the hex output."}],"resultDescription":"A JSON response containing the hex-encoded HMAC-MD5 digest string computed from the provided text and key. The output is a fixed-length 32-character lowercase hexadecimal string representing the 128-bit HMAC value.","failureModes":["Empty or missing 'key' field returns a validation error","Empty or missing 'text' field returns a validation error","Key exceeding 512 characters is rejected","Text exceeding 100,000 characters is rejected","Payment of $0.009 USDC not provided or failing results in 402 Payment Required","Malformed JSON body returns 400 Bad Request"],"whenToPreferThis":"Choose this endpoint when you need an HMAC-MD5 keyed message authentication code returned as hexadecimal — specifically when MD5 is required (e.g. for compatibility with a legacy system, AWS S3 request signing, or an API that mandates HMAC-MD5). Prefer the free sandbox endpoint POST /v1/sandbox/hmac-md5-hex for testing. Use sibling endpoints if you need a different hash algorithm (SHA-512, SHAKE128) or a different encoding (base64, base32).","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-01T00:52:38.307Z","isFirstParty":false,"canonicalSlug":"hmac-md5-hex-digest-agentshelf-syntexa-ch-d957a80d"}