Discover / postal.openverbs.com

List supported countries

■ Challenge detected

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

x402
Base
USDC

Listed price: $0.002
Challenge detected: 9 of the last 9 checks
Median response: 178 ms
Last checked: 16 Oct, 16:44 UTC
In our index since: 26 Sept 2026

Endpoint

curl -i https://postal.openverbs.com/v1/countries
# 402 Payment Required: pay with an x402 client (USDC on Base),
# then send the same request again with the payment attached.

4 listed endpoints · on x402 Bazaar

Checks and payment terms on this page refer to the endpoint above. Other listed endpoints have not been checked individually.

Base URLhttps://postal.openverbs.com/v1

POST/spec$0.002Return the validation regular expression (source and flags) used for a country's postal codes.
POST/validate$0.002Check whether a postal / ZIP code is well-formed for a country (ISO 3166-1 alpha-2). A malformed code is a successful result with `valid:false`, not an error — only an unsupported country or empty code is a 400.
POST/format$0.002Normalise a postal code's casing and whitespace (uppercase, collapse runs of spaces) and report whether the normalised form is valid for the country.
POST/countries$0.002List every ISO 3166-1 alpha-2 country code for which a postal-code pattern is available.

A dash means the listing gives no price or method. Copy buttons copy the full URL.

Showing 4 of 4 listed endpoints.

Agents can find it through the Superstables MCP server and JSON API: GET /api/v1/services/postal.openverbs.com

Recent checks

3 Oct 2026One bar per check, showing up to 20 recent checks. Coloured bars show relative response time, with a minimum visible height; full-height grey bars mean no challenge was detected. “Challenge detected” means HTTP 402 or another detected payment-challenge signal.16 Oct 2026

All 9 checks

When (UTC)	Result	HTTP	Response
16 Oct, 16:44 UTC	Challenge detected	402	167ms
15 Oct, 08:20 UTC	Challenge detected	402	270ms
14 Oct, 00:19 UTC	Challenge detected	402	178ms
12 Oct, 00:34 UTC	Challenge detected	402	279ms
10 Oct, 12:38 UTC	Challenge detected	402	203ms
9 Oct, 09:34 UTC	Challenge detected	402	242ms
8 Oct, 03:32 UTC	Challenge detected	402	160ms
7 Oct, 00:45 UTC	Challenge detected	402	171ms
3 Oct, 05:05 UTC	Challenge detected	402	178ms

Questions

Did our last probe detect a payment challenge?

At our last probe on 16 Oct, 16:44 UTC, it returned HTTP 402 or another detected payment-challenge signal. This check did not test payment, delivery or compatibility with the Superstables client.

What price is recorded for List supported countries?

Its listed price is $0.002.

What payment terms does List supported countries advertise?

The listing advertises x402, Base and USDC. It names cdp as its facilitator. Check the seller's current payment challenge and authentication requirements before paying.

Where is List supported countries listed?

In x402 Bazaar. Superstables first indexed it on 26 Sept 2026.

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