diff --git a/action.yml b/action.yml
index e419f98..a3d8f6b 100644
--- a/action.yml
+++ b/action.yml
@@ -94,9 +94,9 @@ inputs:
   review_model:
     description: "Override the model used for code review (e.g., 'claude-sonnet-4-5-20250929', 'gpt-5.1-codex'). Only applies to review flows."
     required: false
-    default: "gpt-5.2"
+    default: "claude-opus-4-6"
   reasoning_effort:
-    description: "Override reasoning effort for review flows (passed to Droid Exec as --reasoning-effort). If empty and review_model is also empty, the action defaults internally to gpt-5.2 at high reasoning."
+    description: "Override reasoning effort for review flows (passed to Droid Exec as --reasoning-effort). If empty and review_model is also empty, the action defaults internally to claude-opus-4-6 at high reasoning."
     required: false
     default: "high"
   review_use_validator:
diff --git a/review/action.yml b/review/action.yml
index 6d8e620..7bd4439 100644
--- a/review/action.yml
+++ b/review/action.yml
@@ -15,7 +15,7 @@ inputs:
   review_model:
     description: "Model to use for review"
     required: false
-    default: "gpt-5.2"
+    default: "claude-opus-4-6"
   reasoning_effort:
     description: "Reasoning effort for review (passed to Droid Exec as --reasoning-effort)"
     required: false
diff --git a/test/modes/tag/review-command.test.ts b/test/modes/tag/review-command.test.ts
index 5b8b8af..018d7c8 100644
--- a/test/modes/tag/review-command.test.ts
+++ b/test/modes/tag/review-command.test.ts
@@ -390,7 +390,7 @@ describe("prepareReviewMode", () => {
       (call: unknown[]) => call[0] === "droid_args",
     ) as [string, string] | undefined;
     // When neither REVIEW_MODEL nor REASONING_EFFORT is provided, no --model or --reasoning-effort
-    // flags are added. Defaults are handled by the action.yml inputs (gpt-5.2 / high).
+    // flags are added. Defaults are handled by the action.yml inputs (claude-opus-4-6 / high).
     expect(droidArgsCall?.[1]).not.toContain("--model");
     expect(droidArgsCall?.[1]).not.toContain("--reasoning-effort");
   });
diff --git a/test/review-model-default-sync.test.ts b/test/review-model-default-sync.test.ts
new file mode 100644
index 0000000..80fd06e
--- /dev/null
+++ b/test/review-model-default-sync.test.ts
@@ -0,0 +1,31 @@
+import { describe, expect, it } from "bun:test";
+import { readFileSync } from "node:fs";
+import { join } from "node:path";
+
+function extractReviewModelDefault(yaml: string): string {
+  const match = yaml.match(
+    /review_model:\n(?:\s+.*\n)*?\s+default:\s*"([^"]+)"/,
+  );
+
+  expect(match).toBeTruthy();
+  return match?.[1] ?? "";
+}
+
+describe("review_model default sync", () => {
+  it("keeps review_model default in sync between action manifests", () => {
+    const rootActionYaml = readFileSync(
+      join(process.cwd(), "action.yml"),
+      "utf8",
+    );
+    const reviewActionYaml = readFileSync(
+      join(process.cwd(), "review", "action.yml"),
+      "utf8",
+    );
+
+    const rootDefault = extractReviewModelDefault(rootActionYaml);
+    const reviewDefault = extractReviewModelDefault(reviewActionYaml);
+
+    expect(rootDefault).toBe(reviewDefault);
+    expect(rootDefault.length).toBeGreaterThan(0);
+  });
+});