diff --git a/packages/ai/test/anthropic-signature-hint.test.ts b/packages/ai/test/anthropic-signature-hint.test.ts
index 514b385f6..19b94ceb6 100644
--- a/packages/ai/test/anthropic-signature-hint.test.ts
+++ b/packages/ai/test/anthropic-signature-hint.test.ts
@@ -38,14 +38,8 @@ describe("#4297 anthropic-messages replay-unsigned-thinking hint", () => {
 		expect(isInvalidThinkingSignatureError("Invalid signature in thinking block")).toBe(true);
 		// #4192 fixture wording — no trailing `block`. The pattern MUST accept
 		// both because ZenMux / #4192 documents the failure this shorter way.
-		expect(
-			isInvalidThinkingSignatureError(
-				"messages.1.content.0: Invalid `signature` in `thinking`",
-			),
-		).toBe(true);
-		expect(
-			isInvalidThinkingSignatureError("messages.1.content.0: Invalid signature in thinking"),
-		).toBe(true);
+		expect(isInvalidThinkingSignatureError("messages.1.content.0: Invalid `signature` in `thinking`")).toBe(true);
+		expect(isInvalidThinkingSignatureError("messages.1.content.0: Invalid signature in thinking")).toBe(true);
 	});
 
 	it("does not fire on unrelated errors", () => {