# Vokko Pay-Preflight Host Probe

> Vokko Pay-Preflight Host Probe is a paid API for AI agents from www.vokko.eu, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-31).

Check whether a given domain accepts agent payments by probing it for x402 and other agent payment rails, returning payment readiness and endpoint details.

## Facts

- Endpoint: GET https://www.vokko.eu/api/v1/hosts/%7Bdomain%7D/pay-preflight?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/vokko-pay-preflight-host-probe-bc37aec0
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_5xgNe4-otLR7Ift4athky

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 vokko-pay-preflight-host-probe-bc37aec0
```

Example prompt: Can you check whether stripe.com supports agent payments — like x402 or any other AI payment rails?

## When to prefer this

Use this endpoint when an AI agent needs to determine before attempting a payment whether a given host supports agent-native payment protocols like x402. It is preferable over attempting a live payment blindly, and more efficient than manually inspecting a site's headers or documentation. Best for pre-flight validation in autonomous shopping, API access, or agent-to-merchant workflows.

## Known failure modes

- Domain not resolvable or unreachable — returns unknown or error status
- Domain exists but exposes no payment protocol signals — acceptsAgentPayments: 'unknown'
- Rate limiting or network timeout during probe
- Malformed domain input returns a validation error

## How this service works

Probe a host for UCP, ACP, AP2, TAP, MCP, A2A, x402, MPP, llms.txt and OpenAPI. UCP is one cell — not the product.

## Output

Returns a JSON object with the queried domain, its detected payment intent, and an 'acceptsAgentPayments' field indicating whether the host supports agent payment protocols (e.g. x402). May include details on which rails or endpoints were detected.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "pathParams": {
     "type": "object",
     "required": [
      "domain"
     ],
     "properties": {
      "domain": {
       "type": "string",
       "description": "Host to check"
      }
     }
    },
    "queryParams": {
     "type": "object",
     "properties": {}
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "domain": "example.com",
  "intent": "any",
  "acceptsAgentPayments": "unknown"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/vokko-pay-preflight-host-probe-bc37aec0/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from www.vokko.eu](https://www.zero.xyz/host/www.vokko.eu/llms.txt)