# ChainVerdict Payment Verification API

> ChainVerdict Payment Verification API is a paid API for AI agents from chainverdict.xyz, paid per call via x402, $0.02/call, status unknown (last checked 2026-10-19).

Verifies whether a blockchain transaction constitutes a valid payment for a given transaction hash

## Facts

- Endpoint: GET https://chainverdict.xyz/v1/verify/payment/%7Btx%7D?utm_source=zero.xyz
- Price: $0.02/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-19
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/chainverdict-payment-verification-api-e356c584
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_4dMxTQXomVwdl_AdHLE3R

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 chainverdict-payment-verification-api-e356c584
```

Example prompt: Can you verify whether transaction hash 0xabc123...def456 is a valid payment using ChainVerdict?

## When to prefer this

Use ChainVerdict when you need a quick, pay-per-call on-chain payment verification by transaction hash without setting up your own blockchain node or indexer. It is well-suited for agents that need to gate access or confirm crypto payments in real time before fulfilling orders, releasing assets, or logging payment receipts.

## Known failure modes

- Invalid or malformed transaction hash returns an error response
- Transaction hash not found on any supported chain returns a not-found or unverified verdict
- Unpaid API requests receive HTTP 402 with payment requirements before any result is returned
- Network timeouts if the underlying blockchain RPC is slow or unavailable
- Transaction exists but is pending/unconfirmed may return an inconclusive or pending verdict

## How this service works

x402 v2 pay-per-call. Unpaid requests receive HTTP 402 with payment requirements.

## Output

Returns a verdict object indicating whether the specified blockchain transaction hash represents a valid, confirmed payment, along with supporting transaction details such as status, amount, and chain information.

## 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": [
      "tx"
     ],
     "properties": {
      "tx": {
       "type": "string",
       "description": "Base transaction hash"
      }
     }
    },
    "queryParams": {
     "type": "object",
     "properties": {}
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "additionalProperties": true
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/chainverdict-payment-verification-api-e356c584/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from chainverdict.xyz](https://www.zero.xyz/host/chainverdict.xyz/llms.txt)