{"uid":"cap_O_zNVNx26j_rALzxUoJ-M","slug":"agent-forge-hmac-sha256-a801a396","name":"Agent Forge HMAC-SHA256","description":"Hash and unit utilities for AI agents: SHA-256, SHA-1, HMAC-SHA256, stable JSON fingerprint, ETH/Gwei/Wei conversion, human bytes, and duration parsing. Pay-per-request USDC via x402. No API keys, no accounts.","url":"https://agent-forge.annushka1190.workers.dev/v1/hmac","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":{"body":{"type":"object"},"type":{"const":"http"},"method":{"enum":["POST"]},"bodyType":{"const":"json"}}}}},"responseSchema":{"type":"json","example":{"ok":true}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.003","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":"$0.003/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.003","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.003","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_bCziO5oMBS047fGzMUqss","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.003","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Computes an HMAC-SHA256 message authentication code for a given message and secret key, payable per-request in USDC via x402.","exampleAgentPrompt":"Compute an HMAC-SHA256 signature for the message 'order-id:12345' using the secret key 'my-webhook-secret' — pay per request, no API key needed.","exampleUseCases":[{"title":"Webhook signature validation","prompt":"I need to generate an HMAC-SHA256 signature for this webhook payload '{\"event\":\"payment.completed\",\"amount\":100}' using my secret 'whsec_abc123' so I can attach it to the outgoing request header for verification."},{"title":"API request signing for agent","prompt":"Sign the string 'GET /api/orders?timestamp=1716000000' with the secret key 'agent-api-secret-xyz' using HMAC-SHA256 so my agent can authenticate the request to the external service."},{"title":"Data integrity tag for stored records","prompt":"Generate an HMAC-SHA256 authentication tag for the JSON payload '{\"user\":\"alice\",\"action\":\"transfer\",\"amount\":500}' using secret 'record-integrity-key' before I write it to the database."}],"resultDescription":"Returns a JSON object with ok: true and the computed HMAC-SHA256 digest (hex string) for the provided message and secret key combination.","failureModes":["Missing required 'input' field returns a validation error","Missing secret key or message body causes computation failure","Invalid JSON body results in 400-level error","Payment failure via x402 (insufficient USDC balance) blocks the request","Network timeout on the Cloudflare Worker edge node"],"whenToPreferThis":"Choose this endpoint when your AI agent needs to compute HMAC-SHA256 on-the-fly without managing API keys or accounts, especially in pay-per-use autonomous workflows. Ideal for agents that need to sign webhook payloads, authenticate API requests, or validate data integrity as a one-off computation billed in micro-USDC via x402.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-13T12:36:02.892Z","isFirstParty":false}