base-price-oracle-mcp

Instructions

Implementation Reference

• src/index.ts:830-870 (handler)

  The handler logic for 'compare_prices' which fetches token decimals, identifies DEX pools, and calculates/compares prices across them.

  async ({ token_address }) => {
    try {
      const quoteAddress = WETH;
      const [tokenDecimals, quoteDecimals, tokenSymbol] = await Promise.all([
        getTokenDecimals(token_address),
        getTokenDecimals(quoteAddress),
        getTokenSymbol(token_address),
      ]);
  
      const pools = await findAllPools(token_address, quoteAddress);
      if (pools.length === 0) {
        return { content: [{ type: "text" as const, text: `No DEX pools found for ${token_address} on Base.` }] };
      }
  
      if (pools.length === 1) {
        const price = calculatePrice(pools[0], tokenDecimals, quoteDecimals);
        return {
          content: [{
            type: "text" as const,
            text: JSON.stringify({
              token: token_address,
              symbol: tokenSymbol,
              message: "Only one pool found. No cross-DEX comparison possible.",
              pool: { dex: pools[0].dex, address: pools[0].address, price: formatEth(price) },
            }, null, 2),
          }],
        };
      }
  
      const priceData = pools
        .map((pool) => ({
          dex: pool.dex,
          pool: pool.address,
          price: calculatePrice(pool, tokenDecimals, quoteDecimals),
        }))
        .filter((p) => p.price > 0)
        .sort((a, b) => a.price - b.price);
  
      if (priceData.length < 2) {
        return { content: [{ type: "text" as const, text: "Not enough pools with valid prices to compare." }] };
      }

• src/index.ts:824-829 (registration)

  Registration of the 'compare_prices' tool.

  server.tool(
    "compare_prices",
    "Compare a token's price across multiple DEX pools to find arbitrage opportunities",
    {
      token_address: z.string().describe("Token contract address on Base"),
    },