> ## Documentation Index
> Fetch the complete documentation index at: https://docs.cdp.coinbase.com/llms.txt
> Use this file to discover all available pages before exploring further.
# Validate an x402 endpoint
The **validate endpoint** lets sellers and agents check that an x402 endpoint's Bazaar-discovery configuration is correct *before* going live. CDP probes the seller's URL live, runs a set of preflight checks, and reports whether the [CDP Facilitator](/x402/core-concepts/facilitator) would index the resource for [Bazaar discovery](/x402/bazaar).
This endpoint is **read-only**: it performs no payment and does not index the resource. Use it as a pre-flight check while wiring up your route, and again any time you change your payment requirements or Bazaar extension.
```
POST https://api.cdp.coinbase.com/platform/v2/x402/validate
```
No API key is required — this route is unauthenticated, like the [discovery endpoints](/x402/bazaar#cdp-discovery-endpoints-http).
For the full OpenAPI schema and status codes, see [Validate x402 endpoint](/api-reference/v2/rest-api/x402-facilitator/validate-x402-endpoint) in the x402 Facilitator API Reference.
## Request
| Field | Type | Required | Description |
| ---------- | ------ | -------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `resource` | string | Yes | HTTPS URL of the x402 endpoint to validate. Must use the `https://` scheme. |
| `method` | string | No | HTTP method used to probe the endpoint. Only `GET` and `POST` are supported (default `GET`); other verbs are rejected because x402 resources are expected to respond to these methods. |
```bash theme={null}
curl -X POST https://api.cdp.coinbase.com/platform/v2/x402/validate \
-H "Content-Type: application/json" \
-d '{
"resource": "https://api.example.com/weather/forecast",
"method": "GET"
}'
```
## Response
The response gives you the observed facts about your endpoint, the individual preflight check results, the facilitator's simulated accept/reject decision, and — if your endpoint is already indexed — its current Bazaar index status.
```json theme={null}
{
"valid": true,
"statusCode": 402,
"x402Version": 2,
"preflight": [
{
"check": "reachable",
"passed": true,
"detail": "Endpoint responded to the probe request.",
"severity": "required"
},
{
"check": "returns_402",
"passed": true,
"detail": "Endpoint responded with HTTP 402 Payment Required.",
"expected": "402",
"actual": "402",
"severity": "required"
},
{
"check": "has_bazaar_extension",
"passed": true,
"detail": "Endpoint advertises an extensions.bazaar block.",
"severity": "required"
},
{
"check": "parse",
"passed": true,
"detail": "Payment requirements parsed successfully.",
"severity": "required"
}
],
"paymentRequirements": {
"scheme": "exact",
"network": "eip155:8453",
"amount": "1000",
"asset": "0x...",
"payTo": "0x...",
"maxTimeoutSeconds": 60
},
"bazaarExtension": {
"info": { "input": { "type": "http", "method": "GET" } },
"schema": {}
},
"simulation": {
"outcome": "accepted"
},
"index": {
"active": true,
"lastCrawledAt": "2026-06-01T12:00:00Z",
"quality": {
"l30DaysTotalCalls": 42,
"l30DaysUniquePayers": 15,
"lastCalledAt": "2026-06-01T12:00:00Z"
}
}
}
```
### Top-level fields
| Field | Type | Description |
| --------------------- | ----------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| `valid` | `boolean` | `true` if all **required** preflight checks passed and the facilitator would index the resource. |
| `statusCode` | `integer \| null` | HTTP status code the endpoint returned, or `null` if it was not reachable. |
| `x402Version` | `integer \| null` | x402 protocol version advertised by the endpoint, or `null` if it could not be determined. A bare integer (not the version enum) so malformed values are surfaced as-is. |
| `preflight` | `array` | All [preflight check](#preflight-checks) results in run order. |
| `paymentRequirements` | `object \| null` | Raw decoded 402 payment requirements, or `null` if the endpoint was unreachable or the payload was unparseable. Lets you inspect exactly what your endpoint advertises. |
| `bazaarExtension` | `object \| null` | The `extensions.bazaar` block from the endpoint's discovery metadata, or `null` if absent or unreachable. |
| `simulation` | `object` | The [simulated facilitator decision](#simulation). |
| `index` | `object \| null` | [Bazaar index status](#index-status) if the endpoint is already indexed, otherwise `null`. |
### Preflight checks
Each entry in `preflight` reports one check. Well-known `check` names are `reachable`, `returns_402`, `has_bazaar_extension`, and `parse` — additional checks may be added in future versions, so handle unknown values gracefully.
| Field | Type | Description |
| ---------- | --------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `check` | `string` | Name of the check. |
| `passed` | `boolean` | Whether the check passed. |
| `detail` | `string` | Human-readable explanation of the result. |
| `expected` | `string` | The value the check expected, when applicable. |
| `actual` | `string` | The value the check observed, when applicable. |
| `severity` | `string` | `required` — a hard indexing requirement that affects `valid` when it fails; or `advisory` — a quality recommendation (for example, a missing output schema) that improves discoverability but does not make the endpoint invalid. |
### Simulation
| Field | Type | Description |
| ----------------- | -------- | -------------------------------------------------------------------------------------- |
| `outcome` | `string` | `accepted` if the facilitator would index the resource, or `rejected` if it would not. |
| `rejectionReason` | `string` | Reason the resource would be rejected. Present only when `outcome` is `rejected`. |
### Index status
Present only when the endpoint is already indexed in the Bazaar.
| Field | Type | Description |
| --------------- | ---------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `active` | `boolean` | Whether the indexed resource is active and served in discovery results. |
| `lastCrawledAt` | `string \| null` | When the endpoint was last crawled, or `null` if indexed but not yet crawled. |
| `quality` | `object` | Quality metrics (for example `l30DaysTotalCalls`, `l30DaysUniquePayers`, `lastCalledAt`), present only when the endpoint has call history. See [Quality ranking](/x402/bazaar#quality-ranking). |
## How to use it
1. **Before going live** — after wiring up your x402 middleware and [Bazaar extension](/x402/bazaar#extension-architecture), call `validate` to confirm your endpoint returns `402`, advertises a parseable `extensions.bazaar` block, and would be `accepted`.
2. **Inspect what you advertise** — read `paymentRequirements` and `bazaarExtension` to verify the payment terms and discovery metadata your endpoint is actually serving match what you intended.
3. **Fix advisory findings to rank higher** — advisory checks (like a missing output schema) do not block indexing but do affect [quality ranking](/x402/bazaar#quality-ranking). Address them to improve discoverability.
A passing `validate` result confirms your endpoint is *ready to be discovered*, not that it is already in search. Indexing still requires at least one successful **settlement** through the CDP Facilitator — see [When does my endpoint appear?](/x402/bazaar#how-it-works).