refactor(cli): code review cleanup fix for tab+tab (#18967)

packages/cli/src/ui/utils/contextUsage.ts

@@ -0,0 +1,29 @@
+/**
+ * @license
+ * Copyright 2026 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import { tokenLimit } from '@google/gemini-cli-core';
+
+export function getContextUsagePercentage(
+  promptTokenCount: number,
+  model: string | undefined,
+): number {
+  if (!model || typeof model !== 'string' || model.length === 0) {
+    return 0;
+  }
+  const limit = tokenLimit(model);
+  if (limit <= 0) {
+    return 0;
+  }
+  return promptTokenCount / limit;
+}
+
+export function isContextUsageHigh(
+  promptTokenCount: number,
+  model: string | undefined,
+  threshold = 0.6,
+): boolean {
+  return getContextUsagePercentage(promptTokenCount, model) > threshold;
+}