ynab-mcp

Instructions

Implementation Reference

• src/tools/categories.ts:128-153 (handler)

  The tool "get_month_category" is registered here with its input schema and handler function, which calls the YNAB client to retrieve budget category details for a specific month.

  server.registerTool("get_month_category", {
    title: "Get Month Category",
    description: "[1 API call] Get a category's budget details for a specific month",
    inputSchema: {
      budget_id: z.string().default("last-used").describe("Budget ID or 'last-used'"),
      month: z.string().describe("Month in YYYY-MM-DD format (first of month) or 'current'"),
      category_id: z.string().describe("The category ID"),
    },
    annotations: { readOnlyHint: true },
  }, async ({ budget_id, month, category_id }) => {
    try {
      const response = await getClient().categories.getMonthCategoryById(budget_id, month, category_id);
      const c = response.data.category;
      const lines = [
        `Category: ${c.name} (${month})`,
        `Budgeted: ${formatCurrency(c.budgeted)}`,
        `Activity: ${formatCurrency(c.activity)}`,
        `Balance: ${formatCurrency(c.balance)}`,
        `Goal Type: ${c.goal_type ?? "None"}`,
        `Goal Target: ${c.goal_target != null ? formatCurrency(c.goal_target) : "None"}`,
      ];
      return textResult(lines.join("\n"));
    } catch (e: any) {
      return errorResult(e.message);
    }
  });