{"uid":"cap_yrRcFoyc5oFcdbElaxSQ7","slug":"webref-weekday-lookup-0f334647","name":"WebRef Weekday 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/time/weekday_of?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":{"date":{"def":{"type":"string"},"type":"string"},"type":"object","weekStartsOn":{"def":{"type":"default","innerType":{"def":{"type":"enum","entries":{"monday":"monday","sunday":"sunday"}},"enum":{"monday":"monday","sunday":"sunday"},"type":"enum","options":["sunday","monday"]},"defaultValue":"sunday"},"type":"default"}}},"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_hmdg85NaknC487WoNlcTj","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 the day-of-week name for a given date, with configurable week-start (Sunday or Monday)","exampleAgentPrompt":"What day of the week is March 15, 2026? Use Sunday as the start of the week.","exampleUseCases":[{"title":"Scheduling meeting on correct weekday","prompt":"What day of the week does April 1, 2025 fall on? I want to make sure I'm not scheduling something on a weekend — use Monday as the week start."},{"title":"Holiday day-of-week check","prompt":"Tell me what day of the week Christmas Day (December 25, 2025) falls on, with Sunday as the start of the week."},{"title":"Event planning date verification","prompt":"I'm planning an event for September 30, 2026 — what day of the week is that? Use Sunday-based weeks."}],"resultDescription":"Returns the name of the weekday (e.g. 'Monday', 'Friday', 'Sunday') for the specified date, calculated relative to the configured week-start convention (Sunday or Monday).","failureModes":["Invalid or unparseable date string returns an error","Missing required date parameter returns a validation error","Unsupported weekStartsOn value (not 'sunday' or 'monday') causes a bad request","Malformed query parameters may return a 400-level error"],"whenToPreferThis":"Use this endpoint when you need a lightweight, pay-per-call weekday lookup for a specific date without needing a full calendar API. Ideal for agents that need to verify which day of the week a date falls on, especially when they also need other web/time reference utilities from the same service (HTTP status codes, MIME types, duration math). No API key or signup required — perfect for stateless agent workflows.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-22T12:30:17.696Z","isFirstParty":false,"canonicalSlug":"webref-weekday-lookup-0f334647"}