brasil-api-mcp-server

Instructions

Implementation Reference

• src/tools/cnpj.ts:20-34 (handler)

  The main handler function that executes the tool logic: fetches company data for the given CNPJ using brasilApiClient and returns a formatted text response.

  handler: async ({ CNPJ }): Promise<McpResponse> => {
    try {
      const result = await brasilApiClient.cnpj.getBy(CNPJ);
      const content: McpTextContent = {
        type: "text",
        text: `CNPJ ${CNPJ} found:\n${prettifyJson(result.data)}`,
      };
      return {
        content: [content],
      };
    } catch (error: any) {
      console.error(error);
      throw new Error(`Failed to fetch CNPJ ${CNPJ}`);
    }
  },

• src/tools/cnpj.ts:10-14 (schema)

  Zod schema defining the input parameter 'CNPJ' as a string, along with its TypeScript type.

  const getCNPJToolParams = {
    CNPJ: z.string().describe("The CNPJ to query"),
  };
  
  type GetCNPJToolParams = typeof getCNPJToolParams;

• src/index.ts:30-41 (registration)

  Registration of the getCNPJTool by including it in the tools array and calling registerTool on the MCP server for each tool.

  const tools = [
    getCepTool,
    getCepV2Tool,
    getBookByISBNTool,
    getCNPJTool,
    getAllBanksTool,
    getBankByCodeTool,
  ];
  
  tools.forEach((tool) => {
    registerTool(server, tool);
  });

• src/utils/index.ts:8-10 (helper)

  Helper function that registers a tool definition to the MCP server by calling server.tool with its properties.

  export const registerTool = (server: McpServer, tool: McpToolDefinition) => {
    server.tool(tool.name, tool.description, tool.params, tool.handler);
  };