chainlink-sentinel

Instructions

Implementation Reference

• src/mcp/server.ts:207-254 (handler)

  The 'sentinel_compare' tool handler is registered and implemented within the server.ts file, using a loop to iterate through all chains to compare price feeds.

  server.tool(
    "sentinel_compare",
    "Compare a price pair across all available chains to detect cross-chain deviations",
    {
      pair: z.string().describe("Price pair to compare (e.g., BTC/USD, ETH/USD)"),
    },
    async ({ pair }) => {
      const results: FeedData[] = [];
      for (const chain of chains) {
        const feed = await readFeed(chain, pair);
        if (feed) results.push(feed);
      }
  
      if (results.length === 0) {
        return { content: [{ type: "text", text: `No feeds found for ${pair}` }] };
      }
  
      const prices = results.map((r) => r.price);
      const min = Math.min(...prices);
      const max = Math.max(...prices);
      const spread = ((max - min) / min) * 100;
  
      const lines = results.map(
        (r) =>
          `${r.chain.padEnd(12)} $${r.price.toFixed(4).padStart(12)} | updated ${Math.floor(r.staleness / 60)}m ago`
      );
  
      return {
        content: [
          {
            type: "text",
            text: [
              `**${pair} — Cross-Chain Comparison**`,
              `Chains: ${results.length} | Spread: ${spread.toFixed(3)}%`,
              `Min: $${min.toFixed(4)} | Max: $${max.toFixed(4)}`,
              "",
              "```",
              ...lines,
              "```",
              spread > 2
                ? `\n**WARNING**: ${spread.toFixed(2)}% cross-chain spread detected. Possible oracle attack or arbitrage opportunity.`
                : "",
            ].join("\n"),
          },
        ],
      };
    }
  );