# Cron Next 6-Field 3 Occurrences

> Cron Next 6-Field 3 Occurrences is a paid API for AI agents from agentshelf.syntexa.ch, paid per call via x402, $0.009/call, status unknown (last checked 2026-10-02).

Given a 6-field cron expression and an optional start datetime, returns the next 3 UTC scheduled fire times

## Facts

- Endpoint: POST https://agentshelf.syntexa.ch/v1/cron-next-6-3?utm_source=zero.xyz
- Price: $0.009/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-02
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/cron-next-6-field-3-occurrences-6507974b
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_KP_uYeTl5IVPzmokdErCJ

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 cron-next-6-field-3-occurrences-6507974b -d '<json body>'
```

Example prompt: What are the next 3 times the cron expression '0 9 * * 1-5 *' will fire, starting from 2025-06-01T00:00:00Z?

## When to prefer this

Use this endpoint when you need to resolve a 6-field cron expression to its next 3 concrete UTC fire times — for example, to display upcoming job runs to a user, verify scheduling correctness, or drive downstream automation logic. Prefer the free sandbox variant (/v1/sandbox/cron-next-6-3) for development and testing to avoid the $0.009 USDC charge. Choose this over generic date libraries when running in an agent environment without local compute or cron parsing libraries available.

## Known failure modes

- Invalid cron expression (wrong number of fields, illegal characters) returns a 400 error
- Malformed or non-ISO 8601 'from' datetime returns a 400 error
- Expression that never fires (e.g. impossible date combinations) may return an error or empty result
- Payment failure or insufficient USDC balance returns a 402 error
- Sandbox endpoint /v1/sandbox/cron-next-6-3 should be tried first to avoid charges during testing

## How this service works

Call when an agent needs the next 3 UTC times for a 6-field cron expression. Exact $0.009 USDC. Prefer unpaid POST /v1/sandbox/cron-next-6-3 first.

## Output

The endpoint returns the next 3 UTC datetimes at which the given 6-field cron expression would fire, starting at or after the provided 'from' datetime (or the current time if omitted). Results are precise ISO 8601 UTC timestamps suitable for use in scheduling logic, audit trails, or user-facing previews.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "from": {
   "type": "string",
   "format": "date-time",
   "examples": [
    "2026-01-01T00:00:00.000Z"
   ],
   "description": "ISO datetime to count forward from. Omit it to start at the current time."
  },
  "expression": {
   "type": "string",
   "examples": [
    "0 0 * * * *"
   ],
   "maxLength": 200,
   "minLength": 1,
   "description": "Cron expression. The route says whether it is 5 fields or 6 fields. Example: 0 9 * * 1-5."
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/cron-next-6-field-3-occurrences-6507974b/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from agentshelf.syntexa.ch](https://www.zero.xyz/host/agentshelf.syntexa.ch/llms.txt)