# SignalDesk AI – End-of-Month Date Calculator

> SignalDesk AI – End-of-Month Date Calculator 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 last day of the month for a given Gregorian date in UTC

## Facts

- Endpoint: POST https://x402-agent.kariguetoazul.workers.dev/api/date/end-of-month?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-end-of-month-date-calculator-60fe8ecf
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_d42NHhsFYDsqEJR_4dY6E

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-end-of-month-date-calculator-60fe8ecf -d '<json body>'
```

Example prompt: What's the last day of the month for March 15, 2025? I need the exact end-of-month date in YYYY-MM-DD format.

## When to prefer this

Choose this endpoint when you need a reliable, deterministic UTC-aware end-of-month calculation for any Gregorian date, especially when leap year correctness matters. It is a lightweight paid microservice suitable for agentic billing, scheduling, or payroll workflows where a single-call date utility is preferable to implementing calendar logic inline.

## Known failure modes

- Invalid date format (not YYYY-MM-DD) returns an error
- Date string out of valid calendar range may return error
- Non-existent dates (e.g. 2023-02-30) may return validation error
- Network or worker timeout if Cloudflare edge is unavailable
- Payment failure if USDC balance is insufficient for the $0.001 fee

## 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 a single field 'date' with the last calendar day of the month for the input date, formatted as YYYY-MM-DD in UTC (e.g. {"date":"2024-02-29"} for a February 2024 input). Correctly handles leap years and variable month lengths.

## 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": {
  "date": "2024-02-29"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/signaldesk-ai-end-of-month-date-calculator-60fe8ecf/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)