# SperaxOS x402 Markets API

> SperaxOS x402 Markets API is a paid API for AI agents from chat.sperax.io, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-14).

Returns paginated cryptocurrency market data (price, volume, market cap, 24h change) for all coins, payable per-request via x402 USDC micropayment on Base.

## Facts

- Endpoint: GET https://chat.sperax.io/api/x402/markets
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/speraxos-x402-markets-api-900ad561
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_cTzNNsICSx7cH3Gf0h5fk

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 speraxos-x402-markets-api-900ad561
```

Example prompt: Pull me the top 250 cryptocurrencies by market cap right now, priced in USD — I want each coin's name, symbol, current price, market cap, 24h volume, and 24h price change percentage.

## When to prefer this

Choose this endpoint when you need broad cryptocurrency market data (prices, volumes, market caps) across many coins without pre-registering for an API key, and your agent can handle x402 micropayments in USDC on Base. Ideal for pay-as-you-go DeFi intelligence pipelines, trading bots, or portfolio dashboards that need fresh market data on demand. Prefer over traditional market data APIs when avoiding key management overhead or when operating within a Web3/agentic payment workflow.

## Known failure modes

- 402 Payment Required if x402 USDC payment on Base is not attached or insufficient
- Invalid vs_currency value returns empty or error response
- per_page exceeding 250 may be rejected or clamped
- Invalid page number (e.g. page beyond available data) returns empty array
- Network timeout if Base payment settlement is delayed
- Wallet without agentcash identity may face restricted access on free-tier endpoints

## How this service works

AI-powered DeFi intelligence APIs payable via the x402 HTTP payment protocol. No API key required — pay per request with USDC on Base. Identity-only (SIWX) endpoints are free for wallets with an agentcash identity.

## Output

An array of coin objects, each containing the CoinGecko coin ID, human-readable name, ticker symbol, current price in the requested currency, market capitalization, total 24-hour trading volume, and 24-hour price change percentage. Returned as a JSON array, paginated according to the page and per_page parameters.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "page": {
   "type": "integer",
   "description": "Page number"
  },
  "order": {
   "enum": [
    "market_cap_desc",
    "market_cap_asc",
    "volume_desc",
    "volume_asc"
   ],
   "type": "string",
   "description": "Sort order"
  },
  "per_page": {
   "type": "integer",
   "description": "Results per page (default: 100, max: 250)"
  },
  "vs_currency": {
   "type": "string",
   "description": "Target currency (default: usd)"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "array",
 "items": {
  "type": "object",
  "properties": {
   "id": {
    "type": "string",
    "description": "CoinGecko coin ID"
   },
   "name": {
    "type": "string",
    "example": "Bitcoin"
   },
   "symbol": {
    "type": "string",
    "example": "btc"
   },
   "market_cap": {
    "type": "number",
    "example": 1300000000000
   },
   "total_volume": {
    "type": "number",
    "example": 30000000000
   },
   "current_price": {
    "type": "number",
    "example": 67000
   },
   "price_change_percentage_24h": {
    "type": "number",
    "example": 2.5
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/speraxos-x402-markets-api-900ad561/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from chat.sperax.io](https://www.zero.xyz/host/chat.sperax.io/llms.txt)