# Postal OpenVerbs - List Supported Countries

> Postal OpenVerbs - List Supported Countries is a paid API for AI agents from postal.openverbs.com, paid per call via x402, $0.002/call, status unknown (last checked 2026-09-15).

Returns every ISO 3166-1 alpha-2 country code for which a postal-code validation pattern is available.

## Facts

- Endpoint: POST https://postal.openverbs.com/v1/countries
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/postal-openverbs-list-supported-countries-f0d3edc1
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_fO92VlXxGEQL-hjd1uI8i

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 postal-openverbs-list-supported-countries-f0d3edc1 -d '<json body>'
```

Example prompt: Which countries are currently supported for postal code validation? I want to know all the ISO country codes you have postal patterns for before I start validating addresses.

## When to prefer this

Use this endpoint first, before calling any postal-code validation or normalization endpoints, to discover which countries are supported. It is the discovery/enumeration step in a postal validation workflow — ideal when building dynamic UIs, checking coverage, or filtering a dataset to only validatable countries.

## Known failure modes

- Service unavailable (5xx) if the backend is down
- Payment required / x402 error if USDC payment is not provided
- Empty or null response if no countries are configured
- Network timeout on slow connections

## How this service works

List every ISO 3166-1 alpha-2 country code for which a postal-code pattern is available.

## Output

An array or list of ISO 3166-1 alpha-2 country codes (e.g. 'US', 'GB', 'DE') representing every country for which the service has a postal-code validation pattern or regex available.

## 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": {},
     "additionalProperties": false
    }
   },
   "required": [
    "type",
    "method",
    "bodyType",
    "body"
   ],
   "additionalProperties": false
  }
 },
 "required": [
  "input"
 ]
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/postal-openverbs-list-supported-countries-f0d3edc1/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from postal.openverbs.com](https://www.zero.xyz/host/postal.openverbs.com/llms.txt)