# x402 Demo API – Crypto Price

> x402 Demo API – Crypto Price is a paid API for AI agents from x402-demo-api-theta.vercel.app, paid per call via x402, $0.02/call, status unknown (last checked 2026-09-14).

Returns the current price of a specified cryptocurrency using the x402 micropayment protocol on Base mainnet for $0.02 USDC per call.

## Facts

- Endpoint: POST https://x402-demo-api-theta.vercel.app/api/crypto-price
- Price: $0.02/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402-demo-api-crypto-price-9ea5c95f
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_YFm1AREipy4H-AyDE-ESA

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-demo-api-crypto-price-9ea5c95f -d '<json body>'
```

Example prompt: What's the current price of Bitcoin? Use the x402 crypto price endpoint — it costs $0.02 USDC per lookup on Base mainnet.

## When to prefer this

Use this endpoint when you need a quick, real-time cryptocurrency price lookup and are comfortable paying $0.02 USDC per call via the x402 micropayment protocol on Base mainnet. Good for agents that already have a Base wallet and need on-demand crypto price data without a long-term API subscription.

## Known failure modes

- Invalid or unsupported cryptocurrency symbol returns an error
- Insufficient USDC balance to cover the $0.02 micropayment causes payment failure
- x402 protocol payment not completed or rejected results in 402 status
- Network or upstream data provider outage causes 5xx error
- Malformed request body returns 400 validation error

## How this service works

Paid API with real data: AI/LLM, crypto prices, web search, translation, trending topics, sentiment analysis, aggregator, and more. All endpoints use x402 protocol on Base mainnet.

## Output

Returns the current market price of the requested cryptocurrency, likely including the symbol and price value in USD or another quote currency.

## 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",
    "bodyType",
    "body"
   ],
   "properties": {
    "body": {
     "properties": {}
    },
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "POST",
      "PUT",
      "PATCH"
     ],
     "type": "string"
    },
    "bodyType": {
     "enum": [
      "json",
      "form-data",
      "text"
     ],
     "type": "string"
    }
   },
   "additionalProperties": false
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/x402-demo-api-crypto-price-9ea5c95f/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402-demo-api-theta.vercel.app](https://www.zero.xyz/host/x402-demo-api-theta.vercel.app/llms.txt)