# Proofwork Crypto Price API

> Proofwork Crypto Price API is a paid API for AI agents from proofwork-the402-webhook.phase-voice.workers.dev, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-14).

Returns current prices and 24-hour change percentages for one or more cryptocurrencies in a specified fiat currency, payable per request via x402 on Base.

## Facts

- Endpoint: GET https://proofwork-the402-webhook.phase-voice.workers.dev/v1/crypto-price
- 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/proofwork-crypto-price-api-016d8605
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_eQcJDs0z5sYr6HKBi2fuW

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 proofwork-crypto-price-api-016d8605
```

Example prompt: What are the current prices and 24-hour changes for BTC and ETH in USD?

## When to prefer this

Choose this endpoint when you need lightweight, pay-per-use cryptocurrency price lookups with no subscription required, particularly in agentic or automated workflows that already use the x402 micropayment protocol on Base. It is well-suited for fetching prices for multiple coins in a single call and supports non-USD fiat currencies. Prefer alternatives if you need order book depth, historical OHLCV data, or trading execution.

## Known failure modes

- Invalid or unrecognized coin ticker returns no result or an error for that coin
- Unsupported currency code (outside 2-8 alpha chars) returns a 400 validation error
- Empty or missing 'coins' query parameter returns a 400 error
- Payment not fulfilled via x402 results in a 402 Payment Required response
- coins string exceeding 1800 characters may be rejected
- Network or worker downtime returns a 5xx error

## How this service works

Small non-cyber evidence and data APIs payable per request with x402 on Base.

## Output

A JSON object containing a list of coin entries — each with the queried ticker, resolved coin ID, current price in the requested currency, and 24-hour percent change — along with the fiat currency used, a report type label, and the UTC timestamp when the prices were observed.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method",
    "queryParams"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "coins"
     ],
     "properties": {
      "coins": {
       "type": "string",
       "maxLength": 1800,
       "minLength": 1
      },
      "currency": {
       "type": "string",
       "pattern": "^[a-zA-Z]{2,8}$"
      }
     },
     "additionalProperties": false
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "coins": [
   {
    "id": "bitcoin",
    "price": 63000,
    "query": "BTC",
    "change_24h_percent": -0.2
   },
   {
    "id": "ethereum",
    "price": 1880,
    "query": "ETH",
    "change_24h_percent": 0.4
   }
  ],
  "report": "crypto_price",
  "currency": "usd",
  "observed_at": "2026-08-16T00:00:00.000Z"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/proofwork-crypto-price-api-016d8605/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from proofwork-the402-webhook.phase-voice.workers.dev](https://www.zero.xyz/host/proofwork-the402-webhook.phase-voice.workers.dev/llms.txt)