# Merkl Stable Yield Ranking API

> Merkl Stable Yield Ranking API is a paid API for AI agents from golf-evm-math.x402-evm-math.workers.dev, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-29).

Returns ranked stable-yield DeFi campaigns on Base via the Merkl protocol, showing protocol name and net APR percentage per pool.

## Facts

- Endpoint: GET https://golf-evm-math.x402-evm-math.workers.dev/sample/merkl-stable?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-29
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/merkl-stable-yield-ranking-api-eefc9802
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_1HtFOQtGDrYpnsaTscGiJ

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 merkl-stable-yield-ranking-api-eefc9802
```

Example prompt: What are the top-ranked stable yield campaigns on Merkl right now on Base, and which protocol has the highest net APR?

## When to prefer this

Choose this endpoint when you need a fast, ranked view of current stable-coin yield campaigns on Base via the Merkl protocol, especially when you want net APR comparisons across multiple protocols in a single call. Prefer this over manually querying each protocol's own API or on-chain data when you need a consolidated leaderboard with minimal latency.

## Known failure modes

- Merkl data unavailable — upstream API outage returns error or empty campaigns array
- Invalid or missing query parameters return a 400 or empty result
- Payment not settled via x402 — call is blocked with 402 Payment Required before data is returned
- Rate limiting or quota exceeded on the worker returns 429

## How this service works

Exact EVM address, calldata, Uniswap V2/V3 and impermanent-loss math. Pay per call in USDC on Base via x402.

## Output

A JSON object containing the chain name (e.g. 'base') and an array of ranked stable campaigns, each with a rank integer, protocol name string, and net APR percentage (e.g. 37.1%). Campaigns are ordered from highest to lowest net APR.

## Request schema (JSON Schema)

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

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "chain": "base",
  "campaigns": [
   {
    "rank": 1,
    "protocol": "Hyperdrive",
    "net_apr_pct": 37.1
   }
  ]
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/merkl-stable-yield-ranking-api-eefc9802/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from golf-evm-math.x402-evm-math.workers.dev](https://www.zero.xyz/host/golf-evm-math.x402-evm-math.workers.dev/llms.txt)