{"uid":"cap_3cu-NnZVXsD6BEy_hpX_C","slug":"ddg-jwt-inspect-verify-967ab0fe","name":"DDG JWT Inspect & Verify","description":"Decode and verify a JWT: header/claims, signature verification (HS256/384/512 with a shared secret; RS/PS/ES/EdDSA against an inline JWK or a JWKS URL), alg=none rejection, and exp/nbf/iat/iss/aud checks with leeway. Deterministic; secrets and tokens are never stored.","url":"https://agents.daedalusdevelopmentgroup.com/v1/jwt-inspect?utm_source=zero.xyz","method":"POST","headers":{},"bodySchema":{"type":"object","$schema":"https://json-schema.org/draft/2020-12/schema","required":["input","output"],"properties":{"input":{"type":"object","required":["type","method","bodyType","body"],"properties":{"body":{"type":"object"},"type":{"type":"string","const":"http"},"method":{"enum":["POST","PUT","PATCH"],"type":"string"},"bodyType":{"enum":["json","form-data","text"],"type":"string"}},"additionalProperties":true},"output":{"type":"object","required":["type","example"],"properties":{"type":{"type":"string"},"example":{"ok":true}},"additionalProperties":true}}},"responseSchema":null,"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.01","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":"$0.01/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.01","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.01","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_ye7c4rf9Y0L6rN5wc-XPf","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.01","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Decodes and cryptographically verifies a JWT, checking its header, claims, signature (HS256/384/512, RS/PS/ES/EdDSA), and standard claim validity (exp/nbf/iat/iss/aud) with configurable leeway.","exampleAgentPrompt":"Can you verify this JWT for me — check its signature using RS256 against my JWKS URL at https://auth.example.com/.well-known/jwks.json, and confirm the issuer is 'https://auth.example.com' and audience is 'my-api'? Here's the token: eyJhbGciOiJSUzI1NiIsInR5cCI6IkpXVCJ9...","exampleUseCases":[{"title":"Validate incoming API auth token","prompt":"I just received this JWT from a user hitting my API — can you decode it and verify the signature against my JWKS URL at https://auth.myapp.com/.well-known/jwks.json, and tell me if the token is expired or has an invalid issuer?"},{"title":"Security audit for alg=none tokens","prompt":"I need to check whether this JWT uses the 'alg=none' bypass trick — can you inspect its header and flag it if it's using a none algorithm or otherwise looks tampered with?"},{"title":"Verify HMAC-signed token with shared secret","prompt":"Please decode and verify this HS256 JWT using the shared secret 'my-super-secret-key' and check that the audience claim matches 'internal-service' and it hasn't expired yet."}],"resultDescription":"Returns the decoded JWT header (algorithm, key ID, type), all decoded claims (iss, sub, aud, exp, nbf, iat plus any custom claims), a boolean signature verification result, per-claim validation outcomes (expired, not-yet-valid, issuer mismatch, audience mismatch), and a rejection reason if the token fails any check including alg=none.","failureModes":["Invalid or malformed JWT format — token cannot be decoded","Signature verification failure — secret or key does not match","Token expired (exp in the past beyond leeway)","Token not yet valid (nbf in the future beyond leeway)","Issuer mismatch — iss claim does not match expected value","Audience mismatch — aud claim does not match expected value","alg=none token rejected outright","JWKS URL unreachable or returns no matching key ID","Unsupported algorithm specified","Payment not provided or insufficient — 402 response"],"whenToPreferThis":"Choose this endpoint when you need a deterministic, server-side JWT inspection and cryptographic verification service that supports the full range of JWA algorithms (HS256/384/512, RS256/384/512, PS256/384/512, ES256/384/512, EdDSA) and can resolve remote JWKS URLs — especially when you want explicit claim validation (exp/nbf/iat/iss/aud) with leeway, security hardening against alg=none, and a guarantee that secrets and tokens are never stored.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-22T12:40:34.152Z","isFirstParty":false,"canonicalSlug":"ddg-jwt-inspect-verify-967ab0fe"}