bsc-dex-spread

An MCP server that gives your agent one tool — get_dex_spread — returning real-time cross-DEX price & spread data for PancakeSwap v2 + v3 on BSC. Each call is a paid API call: $0.01 USDC on Base mainnet, settled automatically over x402 from your own wallet. No subscription, no account, no API key to request — the agent pays per call.

Backed by a live x402 gateway: https://x402.donnyautomation.com Public usage/proof page: https://x402.donnyautomation.com/stats

The tool

get_dex_spread(pair, fee?)

Real-time cross-DEX price & spread for PancakeSwap v2+v3 on BSC.

• pair (required) — token pair as SYM/SYM; the first symbol is the USD-priceable side. Examples: WBNB/USDC, WBNB/USDT, CAKE/WBNB.
• fee (optional) — a PancakeSwap v3 fee tier (100, 500, 2500, 10000) to restrict the v3 probe. Omit to probe all v3 tiers and v2.

Returns per-venue prices, best buy / best sell venue, the gross cross-DEX spread in bps, liquidity (per-venue TVL + totals), and the source block number. Example:

{
  "pair": "WBNB/USDC", "network": "bsc", "chainId": 56,
  "blockNumber": 107562007, "nativeUsd": 546.6,
  "pricesByVenue": [ { "venue": "pancake", "surface": "v2", "price": 546.6, "tvlUsd": 1234567 }, ... ],
  "bestBuy":  { "venue": "pancakeV3:500", "price": ... },
  "bestSell": { "venue": "biswap",        "price": ... },
  "midSpreadBps": 27.4,
  "crossDex": { "grossSpreadBps": 14.05, "buyVenue": "...", "sellVenue": "...", "surface": "v2v3" },
  "liquidity": { "venues": 7, "totalTvlUsd": ... },
  "ts": "2026-07-01T...", "source": "rpc"
}

Why an agent wants this

Cross-DEX spread is the raw signal behind arbitrage, best-execution routing, and slippage estimation. Instead of running BSC RPC infrastructure and multi-DEX pool math itself, an agent calls one tool and pays a cent for a fresh, block-stamped answer across PancakeSwap v2 + v3 venues.

Cost & wallet model — read this

You bring the wallet. This package ships no keys. The server signs each payment with a private key it reads from its own environment (EVM_PRIVATE_KEY), which you set in your MCP client's server config. That is the design: the buyer (you) pays for the data with the buyer's wallet.

• Per call: $0.01 USDC on Base mainnet (eip155:8453).
• Fund USDC only — zero ETH needed. x402's exact scheme is EIP-3009 transferWithAuthorization: you sign an off-chain USDC authorization and the facilitator broadcasts it and pays the gas. A 0-ETH wallet settles fine.
• Use a low-balance, dedicated wallet. Fund it with just a few dollars of USDC on Base and top it up as needed. Do not point this at your main wallet — the key sits in your MCP client config in plaintext, so treat it as a hot, disposable spending wallet.

Install & configure

npm install -g bsc-dex-spread-mcp

Add it to your MCP client. Claude Desktop / Claude Code (claude_desktop_config.json or .mcp.json):

{
  "mcpServers": {
    "bsc-dex-spread": {
      "command": "npx",
      "args": ["-y", "bsc-dex-spread-mcp"],
      "env": {
        "EVM_PRIVATE_KEY": "0xYOUR_BASE_MAINNET_BUYER_KEY"
      }
    }
  }
}

EVM_PRIVATE_KEY — your Base-mainnet buyer wallet key (0x-prefixed), funded with a few dollars of USDC on Base. Optional GATEWAY_URL overrides the endpoint (defaults to https://x402.donnyautomation.com).

Restart your client; the agent will have get_dex_spread available and will pay $0.01 USDC each time it calls it.

How it works

agent → get_dex_spread(pair)
      → GET https://x402.donnyautomation.com/call?pair=...  (HTTP 402 PAYMENT-REQUIRED)
      → sign EIP-3009 USDC auth with EVM_PRIVATE_KEY → x402 facilitator settles on Base
      → gateway proxies to its BSC DEX reader → 200 with the cross-DEX payload

License

MIT