# BYTE Library x402 Gateway – DeFi Yields Feed

> BYTE Library x402 Gateway – DeFi Yields Feed is a paid API for AI agents from x402.payperbyte.io, paid per call via x402, $0.048829/call, status down (last checked 2026-09-15).

Returns cryptographically signed, EIP-712 provenance-stamped DeFi yield data for AI agents, paid per-call in USDC over x402 with no API key required.

## Facts

- Endpoint: GET https://x402.payperbyte.io/feeds/defi-yields
- Price: $0.048829/call
- Payment: x402
- Status: down
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/byte-library-x402-gateway-defi-yields-feed-37b3b785
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap__66t-6mNhS_yuEvSm_cxS

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-defi-yields-feed-37b3b785
```

Example prompt: Pull the latest DeFi yields feed from BYTE Library — I want the current APY rates across protocols with the cryptographic provenance attestation included, and pay for it automatically from my wallet.

## When to prefer this

Choose this endpoint when you need DeFi yield data that comes with cryptographic provenance guarantees and EIP-712 attestations — ideal for AI agents that must verify data authenticity, for on-chain applications requiring signed data feeds, or when operating in a trustless environment where API-key-based auth is undesirable and micropayment-per-call billing on Base is acceptable.

## Known failure modes

- Insufficient USDC balance in wallet — payment fails and data is not returned
- Invalid or missing x402 payment header — 402 Payment Required response
- Network congestion on Base causing payment settlement delay
- Feed temporarily unavailable — service-side error
- Wallet not configured for Base network — transaction rejected
- Signature verification failure on client side if EIP-712 schema mismatch

## How this service works

Cryptographically attested, first-party data feeds for AI agents — covering crypto markets, DeFi yields, weather, earthquakes, news, code-pulse, threat-intel, address reputation, sanctions screening, and supply-chain verdicts. Every paid response carries EIP-712 receipts you verify before acting: (1) a GATEWAY delivery-integrity receipt (X-BYTE-Attestation header, signed by the PayPerByte gateway key) proving these are exactly the bytes we served; and (2) on the 14 attested feeds (provenance:eip712-attested in GET /feeds), a LIVE per-feed PayloadAttestation by that feed's OWN distinct publisher key, anchored ON-CHAIN — recover it from the broadcast the response references via txHash. (Separately, the POST verdict oracles embed their own per-feed `attestation` directly in the response body — recover attestation.signer.) Both attest authenticity + tamper-evidence under the BYTE Library domain. NEITHER asserts the correctness of the underlying data or any verdict, and NEITHER claims an independent third-party data source signed it — all keys are first-party PayPerByte. 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 current DeFi protocol yield rates (APY/APR), cryptographically signed and stamped with an EIP-712 PayloadAttestation proving data provenance. The response includes the feed identifier and structured yield data, delivered after a micropayment of ~$0.048829 USDC settled on Base (eip155:8453).

## Example request

```json
{
 "properties": "apy,tvl,protocol"
}
```

## Request schema (JSON Schema)

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

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "feed": "defi-yields"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/byte-library-x402-gateway-defi-yields-feed-37b3b785/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)