# Wintergreen x402 Methodology Prompt Endpoint

> Wintergreen x402 Methodology Prompt Endpoint is a paid API for AI agents from x402.wintergreen.uk, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-19).

Delivers a specific prompt or intelligence pack (by pack ID and prompt index) from a curated library of crypto trading, quant methodology, and market insights, gated behind a $0.50 USDC micropayment per call.

## Facts

- Endpoint: POST https://x402.wintergreen.uk/api/v1/methodology/prompt/%7Bpack_id%7D/%7Bprompt_idx%7D?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-19
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/wintergreen-x402-methodology-prompt-endpoint-f983df6f
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_f15ImCmyKW_S3gPyZxaib

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-methodology-prompt-endpoint-f983df6f -d '<json body>'
```

Example prompt: Pull pack 'hyperliquid-signals' prompt index 3 from Wintergreen — the one covering liquidation cluster methodology — and pay the $0.50 USDC fee automatically so I can use it in my trading strategy.

## When to prefer this

Choose this endpoint when an AI agent needs specific, curated crypto trading intelligence, quant methodology prompts, or market microstructure insights on demand and can handle x402 micropayment flows. Prefer it over free sources when depth, structure, and validated methodology (e.g. 19-rule kill battery, Kelly sizing) are required. Best suited for agents with built-in x402 payment capability targeting Hyperliquid or ERCOT-adjacent strategies.

## Known failure modes

- HTTP 402 returned if payment header is missing or invalid — agent must sign EIP-712 TransferWithAuthorization and retry
- Invalid pack_id returns 404 or error indicating pack not found
- Out-of-range prompt_idx returns error if index exceeds available prompts in pack
- Insufficient USDC balance or failed on-chain authorization causes payment rejection
- Network or Base chain congestion may delay payment confirmation

## 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

Returns the full text content of the requested prompt or intelligence pack entry — e.g. a detailed methodology write-up, signal description, framework specification, or market analysis — corresponding to the specified pack_id and prompt_idx, after successful USDC payment verification.

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/wintergreen-x402-methodology-prompt-endpoint-f983df6f/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)