Consul MCP Server

Instructions

Implementation Reference

• src/tools/consulTools.ts:358-371 (handler)

  The handler function that executes the get-kv tool logic: retrieves the KV value using consul.kv.get(key), handles errors, formats with formatKVPair, and returns formatted text.

  async ({ key }) => {
    try {
      const data = await consul.kv.get(key);
      if (!data) {
        return { content: [{ type: "text", text: `No value found for key: ${key}` }] };
      }
      
      const kvText = formatKVPair(data);
      return { content: [{ type: "text", text: kvText }] };
    } catch (error) {
      console.error("Error getting KV:", error);
      return { content: [{ type: "text", text: `Error getting value for key: ${key}` }] };
    }
  }

• src/tools/consulTools.ts:352-372 (registration)

  Registration of the get-kv tool via server.tool within registerKVStore function, including description, input schema, and handler.

  server.tool(
    "get-kv",
    "Get a value from the KV store",
    {
      key: z.string().default("").describe("Key to get from the KV store"),
    },
    async ({ key }) => {
      try {
        const data = await consul.kv.get(key);
        if (!data) {
          return { content: [{ type: "text", text: `No value found for key: ${key}` }] };
        }
        
        const kvText = formatKVPair(data);
        return { content: [{ type: "text", text: kvText }] };
      } catch (error) {
        console.error("Error getting KV:", error);
        return { content: [{ type: "text", text: `Error getting value for key: ${key}` }] };
      }
    }
  );

• src/tools/consulTools.ts:355-356 (schema)

  Zod input schema for the get-kv tool defining the 'key' parameter.

  {
    key: z.string().default("").describe("Key to get from the KV store"),

• src/utils/formatter.ts:41-60 (helper)

  Helper function formatKVPair used in the get-kv handler to format the retrieved KV pair, decoding base64-encoded value.

  export function formatKVPair(pair: KVPair): string {
    // Decode base64 value if it exists
    let value = "No value";
    if (pair.Value !== null && pair.Value !== undefined) {
      try {
        // Consul stores values as base64 encoded strings
        value = atob(pair.Value);
      } catch (e) {
        value = pair.Value;
      }
    }
    
    return [
      `Key: ${pair.Key || "Unknown"}`,
      `Value: ${value}`,
      `Flags: ${pair.Flags || 0}`,
      `Last Modified Index: ${pair.ModifyIndex || "Unknown"}`,
      "---",
    ].join("\n");
  }

• src/server.ts:41-41 (registration)

  Invocation of registerKVStore which registers the get-kv tool (among others) on the MCP server.

  registerKVStore(server, consul);