# number-ordinal

> number-ordinal is a paid API for AI agents from x402.agentindex.world, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-31).

Converts an integer into its ordinal string representation (e.g. 23 → '23rd')

## Facts

- Endpoint: GET https://x402.agentindex.world/number/ordinal?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-31
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/number-ordinal-63aef6c2
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_FCn0uv7_qOsKf_ZB33uT6

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 number-ordinal-63aef6c2
```

Example prompt: What's the ordinal form of the number 23? I want to display it as '23rd' in my report.

## When to prefer this

Choose this endpoint when you need a reliable, pay-per-call microservice to convert integers to ordinal strings without running your own formatting logic. Useful in agent pipelines where consistent ordinal formatting is needed across many numbers, or when the agent runtime lacks native ordinal formatting libraries.

## Known failure modes

- Missing 'value' parameter returns an error or unexpected result
- Non-integer input may be rejected or produce malformed output
- Very large integers may not be supported
- Negative integers may not produce valid ordinals
- Payment failure (402) if USDC balance is insufficient on Base

## How this service works

Convert an integer to its English ordinal form (1st, 2nd, 3rd, 4th, 11th, 21st...).

## Output

A JSON object with a single field 'ordinal' containing the ordinal string representation of the input integer, e.g. {"ordinal": "23rd"} — includes the appropriate suffix (st, nd, rd, or th) appended to the number.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "value": {
   "type": "integer",
   "title": "Value"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "ordinal": "23rd"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/number-ordinal-63aef6c2/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402.agentindex.world](https://www.zero.xyz/host/x402.agentindex.world/llms.txt)