# Wintergreen x402 Trust Score Optimization

> Wintergreen x402 Trust Score Optimization is a paid API for AI agents from x402.wintergreen.uk, paid per call via x402, $0.01/call, status down (last checked 2026-10-25).

Returns trust-scoring and x402 endpoint verification guidance for AI agents operating in payment-gated API ecosystems.

## Facts

- Endpoint: GET https://x402.wintergreen.uk/api/v1/knowledge/trust-score-optimization?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: down
- Last checked: 2026-10-25
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/wintergreen-x402-trust-score-optimization-64b4d688
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_Vo9AB-FH-6_4OpG2dKwVM

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 wintergreen-x402-trust-score-optimization-64b4d688
```

Example prompt: Can you fetch the trust score optimization guide from Wintergreen's x402 knowledge base so I know what steps to take to improve my endpoint's P2D badge and credibility rating on x402scan?

## When to prefer this

Choose this endpoint when an AI agent needs structured guidance on evaluating, verifying, or improving the trust score of x402 payment-gated endpoints — particularly when operating in the x402 ecosystem and needing to make trust decisions before committing micropayments. Prefer this over generic API documentation when the specific concern is x402 protocol compliance, P2D badge eligibility, or x402scan discoverability scoring.

## Known failure modes

- HTTP 402 returned if USDC payment via EIP-712 TransferWithAuthorization is not included — agent must sign and retry with X-PAYMENT header
- Invalid or missing _file_slug / _route_slug parameters may return empty or incorrect content
- Response schema is unspecified, so the returned content structure may vary and require parsing
- Payment to wrong address or wrong chain (must be Base / eip155:8453) will fail
- Stale content if knowledge base is not frequently updated

## How this service works

Payment-gated crypto trading intelligence for AI agents.
    
## Categories
- **Hyperliquid Signals**: Real-time funding divergence, lead-lag correlation, liquidation clusters, session volume area levels
- **Quant Methodology**: Backtesting walk-forward validation, strategy generation with kill battery (19 rules), risk management with Kelly sizing, regime detection, execution frameworks, agent orchestration
- **Market Insights**: 22 crypto microstructure observations — funding, liquidation, orderbook, regime, flow, anomaly
- **Power Markets**: ERCOT field guide, merit-order model, duck curve analysis
- **Career Guides**: Firefighter oral board prep, medical coding, ATSA, contractor estimating
- **Trust Scoring**: x402 endpoint verification, P2D badges

## Payment
All paid endpoints return HTTP 402 with USDC on Base (eip155:8453). 
Sign EIP-712 TransferWithAuthorization and retry with X-PAYMENT header.
PayTo: 0xAe9834d71F1Bd989A0dc17593451af823E31CeeD

## Output

A knowledge document describing how x402 endpoints are scored for trustworthiness, how P2D badges are assigned, what verification signals matter (discovery sources, metadata completeness, payment reliability), and actionable steps to optimize an endpoint's trust standing in ecosystems like x402scan.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "_file_slug": {
   "type": "string"
  },
  "_route_slug": {
   "type": "string"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/wintergreen-x402-trust-score-optimization-64b4d688/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402.wintergreen.uk](https://www.zero.xyz/host/x402.wintergreen.uk/llms.txt)