# x402-data-api Stablecoins by Circulating Supply

> x402-data-api Stablecoins by Circulating Supply is a paid API for AI agents from x402-data-api.sigrunner.workers.dev, paid per call via x402, $0.003/call, status unknown (last checked 2026-10-29).

Returns top stablecoins ranked by circulating supply from DefiLlama, including name, symbol, price, peg type, and circulating USD value.

## Facts

- Endpoint: GET https://x402-data-api.sigrunner.workers.dev/crypto/stablecoins?utm_source=zero.xyz
- Price: $0.003/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-29
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402-data-api-stablecoins-by-circulating-supply-dc17afd6
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_5joF2Xm8UjMLmkPrAHA7B

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 x402-data-api-stablecoins-by-circulating-supply-dc17afd6
```

Example prompt: Can you pull the current list of top stablecoins by circulating supply and flag any that look like they might have depegged from $1?

## When to prefer this

Use this endpoint when you need a quick, no-auth, pay-per-call snapshot of the stablecoin market ranked by circulating supply — especially for depeg checks or market share comparisons. Prefer this over building a DefiLlama integration yourself when low cost and simplicity matter. Best suited for agents that need occasional stablecoin market data without a subscription.

## Known failure modes

- DefiLlama upstream unavailable — may return 502 or empty data
- Payment not processed — returns 402 if USDC payment fails
- Invalid `limit` parameter type — may be ignored or cause 400 error
- Rate limiting or worker timeout on Cloudflare edge

## How this service works

Top stablecoins by circulating supply (DefiLlama): name, symbol, price, peg type, circulating USD. No params. Use when an agent needs stablecoin supply and depeg checks.

## Output

A JSON array of top stablecoins, each with symbol, current price (in USD), and circulating supply in USD. Optionally limited by a `limit` query parameter. Data is sourced from DefiLlama and reflects near-real-time supply figures.

## 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"
    },
    "queryParams": {
     "type": "object",
     "properties": {
      "limit": {
       "type": "string"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "required": [
      "stablecoins"
     ],
     "properties": {
      "stablecoins": {
       "type": "array",
       "items": {
        "type": "object",
        "required": [
         "symbol",
         "price",
         "circulating_usd"
        ],
        "properties": {
         "price": {
          "type": "number"
         },
         "symbol": {
          "type": "string"
         },
         "circulating_usd": {
          "type": "integer"
         }
        }
       }
      }
     }
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "stablecoins": [
   {
    "price": 0.9994,
    "symbol": "USDT",
    "circulating_usd": 183456438967
   }
  ]
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/x402-data-api-stablecoins-by-circulating-supply-dc17afd6/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402-data-api.sigrunner.workers.dev](https://www.zero.xyz/host/x402-data-api.sigrunner.workers.dev/llms.txt)