# Crest x402 Service Trust Score

> Crest x402 Service Trust Score is a paid API for AI agents from data.crestsystems.ai, paid per call via x402, $0.5/call, status down (last checked 2026-09-15).

Returns a trust grade, trust score, and spend recommendation for any x402 service receiver address (EVM or Solana).

## Facts

- Endpoint: GET https://data.crestsystems.ai/data/service-trust/%7Baddress%7D
- Price: $0.5/call
- Payment: x402
- Status: down
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/crest-x402-service-trust-score-4344edc1
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_u_XPcEfHX--TGkHgvxxQM

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 crest-x402-service-trust-score-4344edc1
```

Example prompt: Before I pay, can you check the Crest trust score and grade for this x402 service address 0x1234567890abcdef1234567890abcdef12345678 and tell me if I should spend USDC on it?

## When to prefer this

Use this endpoint when an AI agent needs to vet an x402 service receiver address before authorizing a USDC payment on Base mainnet — specifically when you want a letter grade, numeric trust score, and a binary SPEND/AVOID recommendation rather than raw on-chain data. Prefer this over generic wallet analytics when operating within the x402 pay-per-request ecosystem.

## Known failure modes

- Address not found in x402 registry — found: false returned
- Invalid address format (not EVM 0x+40hex or Solana base58) — likely 400 error or empty result
- Payment not processed — 402 response if USDC payment fails
- Unknown or very new address with no activity — low trust_score with limited data
- Network/service downtime — 5xx error

## How this service works

Crypto market data, DeFi analytics, and x402 ecosystem intelligence via pay-per-request USDC on Base mainnet.

## Output

Returns a JSON object with: paid (bool), found (bool), grade (letter grade like 'A-'), address (the queried address), trust_score (integer 0-100), and recommendation (e.g. 'SPEND' or 'AVOID').

## 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"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "address"
     ],
     "properties": {
      "address": {
       "type": "string",
       "description": "x402 service receiver address (EVM 0x+40hex or Solana base58)"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "paid": true,
  "found": true,
  "grade": "A-",
  "address": "0x...",
  "trust_score": 78,
  "recommendation": "SPEND"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/crest-x402-service-trust-score-4344edc1/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from data.crestsystems.ai](https://www.zero.xyz/host/data.crestsystems.ai/llms.txt)