# SignalDesk AI – Day of Week Lookup

> SignalDesk AI – Day of Week Lookup is a paid API for AI agents from x402-agent.kariguetoazul.workers.dev, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-13).

Returns the weekday name and ISO weekday number for a given Gregorian calendar date (UTC)

## Facts

- Endpoint: POST https://x402-agent.kariguetoazul.workers.dev/api/date/day-of-week?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/signaldesk-ai-day-of-week-lookup-c930e187
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_T26B3btqCl1N4Q0r0t-vv

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 signaldesk-ai-day-of-week-lookup-c930e187 -d '<json body>'
```

Example prompt: What day of the week is 2025-12-25?

## When to prefer this

Use this endpoint when you need a reliable, authoritative weekday name or ISO weekday number for an arbitrary Gregorian date without writing date-math logic yourself. It is especially useful for agents handling scheduling, deadline validation, or calendar-aware workflows where getting the correct day of week for a specific UTC date is critical and must be programmatically confirmed rather than estimated.

## Known failure modes

- Invalid date format (not YYYY-MM-DD) returns a 4xx error
- Out-of-range date values (e.g. month 13) return a validation error
- Missing 'date' field in request body causes a bad-request response
- Payment not included or insufficient results in x402 Payment Required response

## How this service works

Evidence-backed autonomous AI jobs and paid data tools. Queue/D1/cron run outside the chat; free quotas and bounded execution apply.

## Output

A JSON object containing the English weekday name (e.g. 'Friday') and the ISO weekday integer (1 = Monday through 7 = Sunday) for the supplied date, interpreted in UTC.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "date": {
   "type": "string",
   "pattern": "^\\d{4}-\\d{2}-\\d{2}$",
   "maxLength": 10,
   "minLength": 10,
   "description": "Gregorian date YYYY-MM-DD, interpreted in UTC."
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "weekday": "Friday",
  "iso_weekday": 5
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/signaldesk-ai-day-of-week-lookup-c930e187/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402-agent.kariguetoazul.workers.dev](https://www.zero.xyz/host/x402-agent.kariguetoazul.workers.dev/llms.txt)