# Agent Trust Layer – HTTP Endpoint Prober

> Agent Trust Layer – HTTP Endpoint Prober is a paid API for AI agents from agent-trust-layer.agent-trust-layer.workers.dev, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-15).

Probes a public HTTP endpoint for availability, latency, HTTP status, x402 payment-challenge support, and response-schema validity.

## Facts

- Endpoint: GET https://agent-trust-layer.agent-trust-layer.workers.dev/verify
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/agent-trust-layer-http-endpoint-prober-3236724d
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_76U87FQr5VJn-k70g4awa

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 agent-trust-layer-http-endpoint-prober-3236724d
```

Example prompt: Can you probe https://api.example.com/data to check if it's currently up, how fast it responds, whether it supports x402 payment challenges, and if its response schema is valid?

## When to prefer this

Use this endpoint when you need to verify the live health, latency, x402 compliance, and schema validity of a specific agent-payable HTTP endpoint before routing agent traffic or making payment decisions. Prefer this over generic uptime monitors when x402 challenge support and response-schema correctness are required signals.

## Known failure modes

- Target URL is unreachable or times out — returns availability=false with latency timeout indicator
- Invalid or malformed URL provided — input validation error
- Target endpoint returns unexpected HTTP status — status is reported but may indicate service degradation
- x402 challenge not detected — endpoint flagged as non-x402-compliant
- Response schema does not match expected format — schema validity flag set to false

## How this service works

Probe an agent-payable HTTP endpoint for current availability, latency, HTTP status, x402 challenge support, and response-schema validity.

## Output

Returns current availability status, measured latency, HTTP status code, whether the endpoint supports x402 challenge-response payment flow, and whether the response schema passes validation.

## 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"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "url"
     ],
     "properties": {
      "url": {
       "type": "string",
       "format": "uri",
       "description": "Public HTTP or HTTPS endpoint to probe"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/agent-trust-layer-http-endpoint-prober-3236724d/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from agent-trust-layer.agent-trust-layer.workers.dev](https://www.zero.xyz/host/agent-trust-layer.agent-trust-layer.workers.dev/llms.txt)