# Wintergreen x402 Trust Feed

> Wintergreen x402 Trust Feed is a paid API for AI agents from x402.wintergreen.uk, paid per call via x402, $0.005/call, status down (last checked 2026-10-25).

Returns a verified trust feed of x402 endpoint verification scores and P2D badges for payment-gated API discovery.

## Facts

- Endpoint: GET https://x402.wintergreen.uk/api/v1/trust/feed?utm_source=zero.xyz
- Price: $0.005/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-feed-3f19a396
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_0CWWF5PdEAXmFftgAXDDi

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-feed-3f19a396
```

Example prompt: Pull the Wintergreen x402 trust feed so I can see which payment-gated endpoints have verified P2D badges and what their trust scores look like — return it as JSON.

## When to prefer this

Choose this endpoint when an agent needs to evaluate the trustworthiness of x402-protocol payment-gated APIs before committing funds, or when building discovery tooling that needs verified P2D badge data. It is specifically designed for x402 ecosystem trust verification, not general API monitoring or crypto trading signals.

## Known failure modes

- HTTP 402 returned if USDC micropayment ($0.01 on Base) has not been submitted — agent must sign EIP-712 TransferWithAuthorization and retry with X-PAYMENT header
- Empty or malformed response schema — endpoint does not publish a defined response schema so output structure may vary
- Payment address mismatch — sending USDC to wrong address results in failed authorization
- Base network congestion causing payment confirmation delay

## 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 structured feed of x402 endpoint trust scores and P2D verification badges, indicating which payment-gated endpoints have been validated by Wintergreen's trust-scoring system. Response format can be requested as JSON via the optional format parameter.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "format": {
   "enum": [
    "json"
   ],
   "type": "string",
   "description": "Optional response format hint (json). No required inputs."
  }
 }
}
```

## Response schema (JSON Schema)

```json
{}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/wintergreen-x402-trust-feed-3f19a396/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)