{"openapi":"3.1.0","info":{"title":"ISO Week Number","version":"1.0.0","summary":"The week number that doesn't depend on which app you asked.","description":"Converts calendar dates to ISO 8601 week-numbering dates and back. Gets right the part every ad-hoc script gets wrong: week 1 is the week containing the first Thursday of the year, so late-December and early-January dates routinely belong to a different ISO year than the calendar year.\n\n**Not for:** Not a general calendar or scheduling tool, and it does not know about business fiscal-year or retail 4-4-5 week numbering, which are different systems that also call themselves \"week numbers.\" It has no concept of time of day or timezone — it operates on calendar dates only. Not for US-style \"week of the month\" or non-ISO week-start conventions (e.g. Sunday-start week numbering used by some US calendars).\n\nFree tier: 250 calls per UTC day per caller. Past that, endpoints return 402 with x402 payment requirements. An MCP server exposing the same capabilities is available at https://iso-week.gumballtools.com/api/mcp.","contact":{"url":"https://github.com/bwalvoord/gumball"}},"servers":[{"url":"https://iso-week.gumballtools.com","description":"Production"}],"externalDocs":{"url":"https://iso-week.gumballtools.com/llms-full.txt","description":"Full documentation for agents"},"paths":{"/api/v1/run":{"get":{"operationId":"run","summary":"The week number that doesn't depend on which app you asked.","description":"TODO: describe what this returns and when to call it.","parameters":[{"name":"input","in":"query","required":true,"description":"TODO: exact format, units, and range.","schema":{"type":"string"}}],"responses":{"200":{"description":"The result.","content":{"application/json":{"schema":{"type":"object"}}}},"400":{"description":"Invalid input. The body names the field and how to fix it.","content":{"application/json":{"schema":{"type":"object","required":["error"],"properties":{"error":{"type":"object","required":["code","message","fix_hint","docs"],"properties":{"code":{"type":"string","description":"Stable machine-readable error code."},"message":{"type":"string"},"fix_hint":{"type":"string","description":"What to change before retrying."},"field":{"type":"string"},"token":{"type":"string"},"examples":{"type":"array","items":{"type":"string"}},"docs":{"type":"string","format":"uri"}}}}}}}},"402":{"description":"Free quota of 250 calls per UTC day exhausted. Body is an x402 v1 payment requirement ($0.001 per call). While settlement is disabled the body carries payment_enabled: false and the call cannot be unblocked by paying — wait for quota.resetsAt.","content":{"application/json":{"schema":{"type":"object"}}}}}}}}}