WhatsApp Business MCP Server

Instructions

Implementation Reference

• src/whatsapp-client.ts:130-146 (handler)

  Actual implementation of the WhatsApp template message sending logic.

  async sendTemplateMessage(
    to: string,
    templateName: string,
    language: string,
    components?: unknown[]
  ) {
    return this.request(`/${this.config.phoneNumberId}/messages`, "POST", {
      messaging_product: "whatsapp",
      to,
      type: "template",
      template: {
        name: templateName,
        language: { code: language },
        ...(components ? { components } : {}),
      },
    });
  }

• src/index.ts:140-159 (registration)

  MCP tool registration for "send_template_message" which calls the handler in WhatsAppClient.

  server.tool(
    "send_template_message",
    "Send a pre-approved template message. Required for initiating conversations outside the 24-hour window. Templates must be approved by Meta before use.",
    {
      to: z.string().describe("Recipient phone number in international format"),
      template_name: z.string().describe("Name of the approved template"),
      language: z.string().default("pt_BR").describe("Template language code (e.g., pt_BR, en_US)"),
      components: z
        .array(z.record(z.string(), z.unknown()))
        .optional()
        .describe("Template components with variable values (header, body, button params)"),
    },
    async ({ to, template_name, language, components }) =>
      executeWithHooks(
        "send_template_message",
        { to, template_name, language, components },
        config,
        () => wa.sendTemplateMessage(to, template_name, language, components)
      )
  );