# Life Dates & Milestones – Weekday of Date

> Life Dates & Milestones – Weekday of Date is a paid API for AI agents from life-dates.x402tookit.com, paid per call via x402, $0.02/call, status unknown (last checked 2026-10-29).

Returns the day of the week, day of year, days left in year, quarter, and leap-year facts for any date from year 1000 onward.

## Facts

- Endpoint: GET https://life-dates.x402tookit.com/weekday-of-date?utm_source=zero.xyz
- Price: $0.02/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-29
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/life-dates-milestones-weekday-of-date-cabcac38
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_s_1Krl3LmgJWqSP8KIzis

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 life-dates-milestones-weekday-of-date-cabcac38
```

Example prompt: What day of the week was July 20, 1969, and was it a weekend? Also tell me what day of the year that was and how many days were left in 1969.

## When to prefer this

Choose this endpoint when you need authoritative calendar metadata for a single date — especially the weekday, day-of-year, days remaining, or quarter — for any date back to year 1000. It is particularly well-suited for historical date lookups, calendar enrichment pipelines, or when leap-year and Julian Day Number data are needed alongside weekday information. Prefer sibling endpoints for age calculations, date differences, or birthday logic.

## Known failure modes

- Missing 'date' query parameter returns a validation error
- Date string in wrong format (not YYYY-MM-DD) returns a parse error
- Date before year 1000 may return an out-of-range error
- Non-existent dates like February 30 return an invalid date error
- Network timeout results in no response

## How this service works

Day of the week for any date from year 1000, with day of year, days left in the year, quarter and leap-year facts.

## Output

Returns a JSON object with the full weekday name, whether the date is a weekend, the day-of-year number, days remaining in the year, the calendar quarter (1–4), leap-year status, month name, number of days in that month, Unix day offset, and Julian Day Number for the requested date.

## 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": [
      "date"
     ],
     "properties": {
      "date": {
       "type": "string",
       "description": "Date as YYYY-MM-DD (proleptic Gregorian calendar)"
      }
     }
    }
   },
   "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"
       ]
      },
      "quarter": {
       "type": [
        "null",
        "number"
       ]
      },
      "reasons": {
       "type": [
        "array",
        "null"
       ]
      },
      "summary": {
       "type": [
        "null",
        "string"
       ]
      },
      "unixDay": {
       "type": [
        "null",
        "number"
       ]
      },
      "verdict": {
       "type": [
        "null",
        "string"
       ]
      },
      "weekday": {
       "type": [
        "null",
        "string"
       ]
      },
      "degraded": {
       "type": [
        "boolean",
        "null"
       ]
      },
      "dayOfYear": {
       "type": [
        "null",
        "number"
       ]
      },
      "isWeekend": {
       "type": [
        "boolean",
        "null"
       ]
      },
      "monthName": {
       "type": [
        "null",
        "string"
       ]
      },
      "disclaimer": {
       "type": [
        "null",
        "string"
       ]
      },
      "isLeapYear": {
       "type": [
        "boolean",
        "null"
       ]
      },
      "notChecked": {
       "type": [
        "array",
        "null"
       ],
       "items": {
        "type": "string"
       }
      },
      "daysInMonth": {
       "type": [
        "null",
        "number"
       ]
      },
      "daysLeftInYear": {
       "type": [
        "null",
        "number"
       ]
      },
      "jul
… (truncated)
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/life-dates-milestones-weekday-of-date-cabcac38/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from life-dates.x402tookit.com](https://www.zero.xyz/host/life-dates.x402tookit.com/llms.txt)