# AgentResolver x402 Ping

> AgentResolver x402 Ping is a paid API for AI agents from agentresolver.vercel.app, paid per call via x402, $0.001/call, status unknown (last checked 2026-09-18).

Verifies x402 payment-settled connectivity by returning a timestamped pong with request echo and settled delivery confirmation.

## Facts

- Endpoint: GET https://agentresolver.vercel.app/api/x402-ping
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-18
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/agentresolver-x402-ping-8ebc4c9f
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_AhbDyZJjsG6TurjJcJ4OS

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 agentresolver-x402-ping-8ebc4c9f
```

Example prompt: Send a test ping to AgentResolver's x402 endpoint with echo text 'hello-agent' and confirm the payment settled and I got a pong back.

## When to prefer this

Choose this endpoint when you need to verify end-to-end x402 micropayment connectivity specifically through AgentResolver, confirm that USDC settlement is working, or establish a latency baseline for paid agent API calls. It is the canonical health-check for the AgentResolver x402 payment pipeline.

## Known failure modes

- Payment not settled — USDC balance insufficient, returns 402 Payment Required
- Invalid or missing x402 payment header — request rejected before processing
- Network timeout reaching agentresolver.vercel.app
- Malformed input — echo field is not a string, returns validation error
- Rate limiting or Vercel cold-start delay causing slow response

## How this service works

No-body $0.001 x402 settlement test for funded agents. Verifies the buyer wallet, facilitator, USDC payment path, and paid delivery end-to-end by returning a timestamped pong only after successful settlement.

## Output

Returns a JSON object with pong: true, settledDelivery: true, an ISO 8601 timestamp, Unix milliseconds, a UUID request ID, and the echoed input string — confirming the payment was processed and the endpoint is reachable.

## 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",
     "properties": {
      "echo": {
       "type": "string",
       "maxLength": 256,
       "description": "Optional text echoed by the paid settlement response."
      }
     },
     "additionalProperties": false
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "required": [
      "pong",
      "settledDelivery"
     ],
     "properties": {
      "pong": {
       "type": "boolean",
       "const": true
      },
      "settledDelivery": {
       "type": "boolean",
       "const": true
      }
     },
     "additionalProperties": true
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "pong": true,
  "settledDelivery": true
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/agentresolver-x402-ping-8ebc4c9f/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from agentresolver.vercel.app](https://www.zero.xyz/host/agentresolver.vercel.app/llms.txt)