# BYTE Library x402 Gateway – Perpetual Funding Rates Feed

> BYTE Library x402 Gateway – Perpetual Funding Rates Feed is a paid API for AI agents from x402.payperbyte.io, paid per call via x402, $0.02/call, status unknown (last checked 2026-09-15).

Returns cryptographically signed, EIP-712 provenance-stamped perpetual futures funding rate data for crypto markets, paid per call in USDC via x402

## Facts

- Endpoint: GET https://x402.payperbyte.io/feeds/perp-funding
- Price: $0.02/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-perpetual-funding-rates-feed-11f2c796
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_bRCN0UaaDYVMx40JUrFSI

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-perpetual-funding-rates-feed-11f2c796
```

Example prompt: Fetch me the current perpetual futures funding rates from the BYTE Library provenance feed — I want the cryptographically signed, EIP-712 attested payload and I'll pay in USDC via x402 on Base.

## When to prefer this

Choose this endpoint when you need cryptographically signed, provenance-verified perpetual futures funding rate data and can pay per call in USDC without managing API keys. Ideal for DeFi agents, on-chain trading bots, or risk systems that need attestable data provenance via EIP-712. Prefer this over traditional REST APIs when trustless data verification and wallet-based authentication matter.

## Known failure modes

- Insufficient USDC payment or missing x402 payment header returns 402 Payment Required
- Invalid or expired payment token results in authentication failure
- Network congestion on Base chain may delay payment settlement
- Feed temporarily unavailable returns 503 or timeout
- Malformed request with invalid properties returns 400 Bad Request

## How this service works

Cross-venue perpetual-swap funding rates (Hyperliquid, dYdX, Aevo live; GMX + Vertex coming v1.1) + spread. Annualized.

## Output

A JSON payload containing the 'perp-funding' feed data, cryptographically signed and stamped with an EIP-712 PayloadAttestation for provenance verification. The response includes current perpetual futures funding rate data for crypto markets. Each payload is verifiable on-chain and priced at $0.007325 USDC per call, settled on Base (eip155:8453).

## Example request

```json
{
 "properties": "funding_rates,mark_price,index_price"
}
```

## 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"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "properties": {}
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/byte-library-x402-gateway-perpetual-funding-rates-feed-11f2c796/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)