# Week Number & Date Details Lookup

> Week Number & Date Details Lookup is a paid API for AI agents from timezone-time.x402tookit.com, paid per call via x402, $0.02/call, status unknown (last checked 2026-10-21).

Returns ISO 8601 week number, week year, day of year, quarter, weekday name, and leap-year status for a given date.

## Facts

- Endpoint: GET https://timezone-time.x402tookit.com/week-number?utm_source=zero.xyz
- Price: $0.02/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-21
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/week-number-date-details-lookup-92ea050b
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_MYIxJVbozXuyvgMvzhVFj

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability week-number-date-details-lookup-92ea050b
```

Example prompt: What ISO week number, quarter, weekday, and day of year is 2025-03-15? Also tell me whether it's a leap year.

## When to prefer this

Use this endpoint when you need ISO 8601 week metadata, day-of-year position, quarter classification, or leap-year determination for a specific date, particularly in scheduling, reporting, or calendar-aware workflows. It is purpose-built for date attribute lookups and returns multiple properties in a single call, avoiding the need to compute these values client-side.

## Known failure modes

- Invalid date format returns an error — must be YYYY-MM-DD
- Dates outside supported range may return null fields
- Missing date parameter defaults to today UTC, which may be unexpected for non-UTC callers
- Degraded mode may return partial results with a degraded flag set to true

## How this service works

ISO 8601 week number and week year, day of the year, quarter, weekday and leap-year status for a date.

## Output

Returns a JSON object with the ISO week number (isoWeek), ISO week year (isoWeekYear), a formatted label like 'W03-2025' (isoWeekLabel), the day of year (dayOfYear), total days in the year (daysInYear), days remaining in the year (daysLeftInYear), the fiscal quarter (quarter), the weekday name (weekday), and a boolean leap year flag (leapYear), plus a human-readable summary. If no date is provided, defaults to today in UTC.

## Request schema (JSON Schema)

```json
{
 "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"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [],
     "properties": {
      "date": {
       "type": "string",
       "description": "YYYY-MM-DD, default today (UTC)"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "properties": {
      "asOf": {
       "type": [
        "null",
        "string"
       ]
      },
      "date": {
       "type": [
        "null",
        "string"
       ]
      },
      "source": {
       "type": [
        "null",
        "string"
       ]
      },
      "isoWeek": {
       "type": [
        "null",
        "number"
       ]
      },
      "quarter": {
       "type": [
        "null",
        "number"
       ]
      },
      "reasons": {
       "type": [
        "array",
        "null"
       ],
       "items": {
        "type": "string"
       }
      },
      "summary": {
       "type": [
        "null",
        "string"
       ]
      },
      "verdict": {
       "type": [
        "null",
        "string"
       ]
      },
      "weekday": {
       "type": [
        "null",
        "string"
       ]
      },
      "degraded": {
       "type": [
        "boolean",
        "null"
       ]
      },
      "leapYear": {
       "type": [
        "boolean",
        "null"
       ]
      },
      "dayOfYear": {
       "type": [
        "null",
        "number"
       ]
      },
      "daysInYear": {
       "type": [
        "null",
        "number"
       ]
      },
      "disclaimer": {
       "type": [
        "null",
        "string"
       ]
      },
      "notChecked": {
       "type": [
        "array",
        "null"
       ],
       "items": {
        "type": "string"
       }
      },
      "isoWeekYear": {
       "type": [
        "null",
        "number"
       ]
      },
      "isoWeekLabel": {
       "type": [
        "null",
        "string"
       ]
      },
      "daysLeftInYear": {
       "type": [
        "null",
        "number"
       ]
  
… (truncated)
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/week-number-date-details-lookup-92ea050b/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from timezone-time.x402tookit.com](https://www.zero.xyz/host/timezone-time.x402tookit.com/llms.txt)