Funding rate arbitrage scanner -- Hyperliquid, Binance, Bybit, OKX cross-venue spreads and annualized yields. Pay-per-call via x402 (USDC on Base L2) -- no API key, no signup, no rate-limit wall.

Part of the klymax402 marketplace -- 100 x402 micropayment APIs for AI agents, one wallet, USDC on Base.

Quickstart -- MCP

Add to your MCP client config (Claude Desktop, Cursor, ElizaOS, etc.):

json

{
  "mcpServers": {
    "funding-arb": {
      "url": "https://funding-arb.api.klymax402.com/mcp"
    }
  }
}

Quickstart -- HTTP (x402)

bash

curl "https://funding-arb.api.klymax402.com/api/scan"
# -> 402 Payment Required, with an x402 payment challenge in the response body

Any x402-aware client (@x402/fetch, x402-agent-tools, ATXP) handles the 402 -> sign -> retry cycle automatically.

Tools

Tool	Method	Path	Price	Description
`perp_scan_funding_arbitrage`	GET	`/api/scan`	$0.002	Scan funding rate arbitrage opportunities across perpetual exchanges

`perp_scan_funding_arbitrage`

Use this when you need to find funding rate arbitrage opportunities across perpetual exchanges. Returns cross-venue spreads in JSON.

Parameters

Name	Type	Required	Description
`symbol`	string	no	Filter by asset symbol (e.g. BTC, ETH, SOL). Optional — scans all assets if omitted.

Returns

opportunities -- array of arb opportunities ranked by annualized yield
symbol -- asset symbol (BTC, ETH, SOL, etc.)
longExchange -- exchange where you go long (lower funding)
shortExchange -- exchange where you go short (higher funding)
spread -- funding rate difference between venues
annualizedYield -- estimated annualized return from the arb
direction -- suggested position direction per exchange

Example response:

json

{"opportunities":[{"symbol":"ETH","longExchange":"Bybit","shortExchange":"OKX","spread":0.0045,"annualizedYield":16.4,"direction":"long Bybit / short OKX"}],"scannedAssets":25,"timestamp":"2026-04-13T12:00:00Z"}

When to use: systematic funding rate arbitrage and delta-neutral carry strategies. Scans all major perpetual venues simultaneously.

Not for: spot prices (use dex_get_swap_quote), DeFi yields (use defi_find_best_yields).

Example agent prompts

"Find funding rate arbitrage opportunities across perpetual exchanges"

Payment

Protocol: x402 -- HTTP-native pay-per-call, no signup, no API key
Network: Base L2 (eip155:8453)
Asset: USDC
Facilitator: Coinbase CDP (primary), PayAI (fallback)
Also reachable via ATXP (OAuth-wrapped x402, RFC 9728 protected-resource metadata)