MCPilot

Instructions

Implementation Reference

• packages/metamask-mcp/src/tools/wait-for-transaction-receipt.ts:16-42 (handler)

  The handler function that executes the tool logic: waits for the transaction receipt using wagmi/core's waitForTransactionReceipt, stringifies the result or error message and returns as MCP content.

  execute: async (args) => {
    try {
      const hash = args.hash as Address
      const chainId = args.chainId as typeof wagmiConfig['chains'][number]['id']
      const result = await waitForTransactionReceipt(wagmiConfig, {
        hash,
        chainId,
      })
      return {
        content: [
          {
            type: "text",
            text: JSONStringify(result),
          },
        ],
      }
    } catch (error) {
      return {
        content: [
          {
            type: "text",
            text: (error as Error).message,
          },
        ],
      }
    }
  },

• packages/metamask-mcp/src/tools/wait-for-transaction-receipt.ts:12-15 (schema)

  Zod input schema defining required 'hash' (string) and optional 'chainId' (number).

  parameters: z.object({
    hash: z.string(),
    chainId: z.coerce.number().optional(),
  }),

• packages/metamask-mcp/src/tools/wait-for-transaction-receipt.ts:8-44 (registration)

  The registration function that defines and adds the tool to the FastMCP server instance.

  export function registerWaitForTransactionReceiptTools(server: FastMCP): void {
    server.addTool({
      name: "wait-for-transaction-receipt",
      description: "Waits for the transaction to be included on a block, and then returns the transaction receipt",
      parameters: z.object({
        hash: z.string(),
        chainId: z.coerce.number().optional(),
      }),
      execute: async (args) => {
        try {
          const hash = args.hash as Address
          const chainId = args.chainId as typeof wagmiConfig['chains'][number]['id']
          const result = await waitForTransactionReceipt(wagmiConfig, {
            hash,
            chainId,
          })
          return {
            content: [
              {
                type: "text",
                text: JSONStringify(result),
              },
            ],
          }
        } catch (error) {
          return {
            content: [
              {
                type: "text",
                text: (error as Error).message,
              },
            ],
          }
        }
      },
    });
  };

• packages/metamask-mcp/src/index.ts:59-59 (registration)

  Top-level call to register the wait-for-transaction-receipt tool during server initialization.

  registerWaitForTransactionReceiptTools(server);