Monad MCP Server

Instructions

Implementation Reference

• src/tools/wallet/balance.ts:20-42 (handler)

  The handler function that implements the core logic of the 'get-mon-balance' tool. It queries the MON balance for the given address on the Monad testnet using viem's publicClient, formats the result using formatUnits with 18 decimals, and returns a formatted text response or error message.

  async ({ address }) => {
      try {
          const balance = await publicClient.getBalance({
              address: address as `0x${string}`,
          });
          return {
              content: [
                  {
                      type: "text",
                      text: `Balance for ${address}: ${formatUnits(balance, 18)} MON`,
                  },
              ],
          };
      } catch (error) {
          return {
              content: [
                  {
                      type: "text",
                      text: `Failed to retrieve balance for address: ${address}. Error: ${error instanceof Error ? error.message : String(error)}`,
                  },
              ],
          };
      }

• src/tools/wallet/balance.ts:17-19 (schema)

  The input schema for the 'get-mon-balance' tool, defined using Zod. Requires a single 'address' parameter as a string describing the Monad testnet address.

  {
      address: z.string().describe("Monad testnet address to check balance for"),
  },

• src/tools/wallet/balance.ts:13-44 (registration)

  The balanceProvider function that registers the 'get-mon-balance' tool with the MCP server using server.tool(), including the tool name, description, input schema, and handler function.

  export function balanceProvider(server: McpServer) {
      server.tool(
          "get-mon-balance",
          "Get MON balance for an address on Monad testnet",
          {
              address: z.string().describe("Monad testnet address to check balance for"),
          },
          async ({ address }) => {
              try {
                  const balance = await publicClient.getBalance({
                      address: address as `0x${string}`,
                  });
                  return {
                      content: [
                          {
                              type: "text",
                              text: `Balance for ${address}: ${formatUnits(balance, 18)} MON`,
                          },
                      ],
                  };
              } catch (error) {
                  return {
                      content: [
                          {
                              type: "text",
                              text: `Failed to retrieve balance for address: ${address}. Error: ${error instanceof Error ? error.message : String(error)}`,
                          },
                      ],
                  };
              }
          }
      );

• src/tools/wallet/index.ts:6-7 (registration)

  Within walletProvider, calls balanceProvider to register the get-mon-balance tool as part of wallet tools.

  balanceProvider(server);
  sendMonProvider(server);

• src/index.ts:24-24 (registration)

  In the main server initialization, calls walletProvider(server) which chains to registering get-mon-balance.

  walletProvider(server);