{"uid":"cap_4PUOxiq8v5BqF6zMFH9M-","slug":"webref-http-method-safety-idempotency-lookup-47a13eee","name":"WebRef HTTP Method Safety & Idempotency Lookup","description":"Web standards and time reference for AI agents: HTTP status codes with what the client should do, retry semantics, MIME types and content-type matching, request-method safety and idempotency, plus deadline arithmetic - time until a moment, weekday and business-day checks, duration conversion and Unix timestamps. Pay per call in USDC on Base via x402 or USDC on Tempo via MPP. No signup, no API key, no KYC.","url":"https://webref.johnaio281.workers.dev/api/web/http_method?utm_source=zero.xyz","method":"GET","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","method":{"def":{"type":"string"},"type":"string"}}},"additionalProperties":false}}},"responseSchema":null,"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_lss93w_PGsfOZNb8Miq72","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":"Returns safety, idempotency, and semantic metadata for a given HTTP request method (GET, HEAD, or DELETE)","exampleAgentPrompt":"Is the HTTP DELETE method safe to retry automatically, and is it idempotent? Look up its semantics so I know how to handle failures in my API client.","exampleUseCases":[{"title":"API client retry policy builder","prompt":"I'm building an HTTP client and need to know whether GET requests are safe and idempotent so I can decide if they should be automatically retried after a timeout."},{"title":"Validating idempotency before destructive call","prompt":"Before I implement auto-retry logic for DELETE requests in my service, can you look up whether DELETE is considered idempotent according to web standards?"},{"title":"Documenting method semantics for team","prompt":"I'm writing internal API guidelines — can you look up the official safety and idempotency properties of HEAD so I can document the correct retry behavior for our team?"}],"resultDescription":"Returns structured metadata about the specified HTTP method, including whether it is safe (has no observable side effects), whether it is idempotent (repeating the call produces the same result), semantic description of the method, and guidance on client retry behavior.","failureModes":["Unsupported method enum value (only GET, HEAD, DELETE accepted) results in validation error","Missing required 'method' field returns an input schema error","Missing required 'type' field (must be 'http') returns an error","Network timeout to workers.dev endpoint","Payment failure via x402 or MPP prevents access"],"whenToPreferThis":"Choose this endpoint when an AI agent or API client needs authoritative, machine-readable lookup of HTTP method safety and idempotency properties at runtime — especially when implementing retry logic, building documentation, or making decisions about whether a failed request can be safely retried. Covers GET, HEAD, and DELETE. Use sibling WebRef endpoints for HTTP status codes, MIME types, or time/deadline arithmetic.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-22T12:40:34.151Z","isFirstParty":false,"canonicalSlug":"webref-http-method-safety-idempotency-lookup-47a13eee"}