# Payment Card Number Masking

> Payment Card Number Masking is a paid API for AI agents from creditcard.openverbs.com, paid per call via x402, $0.002/call, status unknown (last checked 2026-09-14).

Masks a payment card number, replacing middle digits with a configurable mask character (default *)

## Facts

- Endpoint: POST https://creditcard.openverbs.com/v1/mask
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/payment-card-number-masking-e13275cf
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_8el1otmv8w6SpeKh-IXXz

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 payment-card-number-masking-e13275cf -d '<json body>'
```

Example prompt: Can you mask this credit card number '4111 1111 1111 1111' for me using '#' as the mask character so I can safely display it to the user?

## When to prefer this

Use this endpoint when you need to quickly mask a raw card number for display, logging, or storage purposes without building custom redaction logic. Ideal for PCI-conscious workflows where raw card digits must never appear in UIs, logs, or receipts. Supports custom mask characters for flexible formatting needs.

## Known failure modes

- Missing or empty 'number' field returns a validation error
- Card number exceeding 40 characters is rejected
- Invalid mask character (more than one character) causes an error
- Malformed request body returns a 400-level error
- Payment not settled (x402) returns a 402 Payment Required response

## How this service works

Mask a card number for display, keeping the first six and last four digits (the PCI-permitted maximum) and replacing the rest with a mask character (default `*`).

## Output

Returns a masked version of the provided card number, where sensitive digits are replaced with the specified mask character (default '*'), leaving only the card's non-sensitive portions visible.

## Request schema (JSON Schema)

```json
{
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "type": "object",
 "properties": {
  "input": {
   "type": "object",
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "type": "string",
     "enum": [
      "POST"
     ]
    },
    "bodyType": {
     "type": "string",
     "enum": [
      "json",
      "form-data",
      "text"
     ]
    },
    "body": {
     "type": "object",
     "properties": {
      "number": {
       "type": "string",
       "minLength": 1,
       "maxLength": 40,
       "description": "Card number; spaces and hyphens are allowed."
      },
      "maskChar": {
       "type": "string",
       "minLength": 1,
       "maxLength": 1,
       "description": "Mask character. Default *."
      }
     },
     "required": [
      "number"
     ],
     "additionalProperties": false
    }
   },
   "required": [
    "type",
    "method",
    "bodyType",
    "body"
   ],
   "additionalProperties": false
  }
 },
 "required": [
  "input"
 ]
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/payment-card-number-masking-e13275cf/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from creditcard.openverbs.com](https://www.zero.xyz/host/creditcard.openverbs.com/llms.txt)