# BYTE Library x402 Gateway – Crypto Top 100 Feed

> BYTE Library x402 Gateway – Crypto Top 100 Feed is a paid API for AI agents from x402.payperbyte.io, paid per call via x402, $0.029297/call, status unknown (last checked 2026-09-15).

Returns cryptographically signed, EIP-712 provenance-stamped market data for the top 100 cryptocurrencies, paid per call in USDC via x402.

## Facts

- Endpoint: GET https://x402.payperbyte.io/feeds/crypto-top100
- Price: $0.029297/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/byte-library-x402-gateway-crypto-top-100-feed-3076bc95
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_LMaqmlDI4oAHTUc6ibtrd

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 byte-library-x402-gateway-crypto-top-100-feed-3076bc95
```

Example prompt: Pull the latest cryptographically signed market data for the top 100 cryptocurrencies from the BYTE Library feed — I need prices and rankings with provenance attestations, and I'm happy to pay per call in USDC.

## When to prefer this

Choose this endpoint when you need tamper-evident, cryptographically attested crypto market data for the top 100 coins and your agent workflow requires provenance guarantees. Prefer it over unsigned REST feeds when auditability, on-chain attestation, or trustless data verification matters. Also ideal when you want API-key-free access using a crypto wallet and USDC micropayments on Base.

## Known failure modes

- Payment not included or insufficient USDC — returns HTTP 402 with payment requirements
- Invalid x402 payment header — returns authorization error
- Network or feed unavailability — returns 5xx error
- Stale or delayed market data if upstream feed lags
- Wallet not configured for Base network — payment settlement fails

## How this service works

Verified, provenance-first data feeds for AI agents. Every payload is cryptographically signed and EIP-712 PayloadAttestation provenance-stamped — covering crypto markets, DeFi yields, weather, earthquakes, news, code-pulse, threat-intel, and a slashable fact-oracle. Pay per call in USDC over x402 with no API keys — a wallet, not a secret on the box. Settlement is on Base (eip155:8453). Price is per-feed, derived from expected payload size at $0.005000/KB (floor $0.001000).

## Output

A JSON payload containing market data (prices, rankings, etc.) for the top 100 cryptocurrencies, cryptographically signed and stamped with an EIP-712 PayloadAttestation for provenance verification. Settled on Base (eip155:8453) after USDC payment via x402.

## Example request

```json
{
 "properties": "price,market_cap,volume,rank"
}
```

## Request schema (JSON Schema)

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

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "feed": "crypto-top100"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/byte-library-x402-gateway-crypto-top-100-feed-3076bc95/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402.payperbyte.io](https://www.zero.xyz/host/x402.payperbyte.io/llms.txt)