diff --git a/spring-ai-client-chat/src/main/java/org/springframework/ai/chat/evaluation/FactCheckingEvaluator.java b/spring-ai-client-chat/src/main/java/org/springframework/ai/chat/evaluation/FactCheckingEvaluator.java
index 870b876631c..cb094422cd2 100644
--- a/spring-ai-client-chat/src/main/java/org/springframework/ai/chat/evaluation/FactCheckingEvaluator.java
+++ b/spring-ai-client-chat/src/main/java/org/springframework/ai/chat/evaluation/FactCheckingEvaluator.java
@@ -134,7 +134,7 @@ public EvaluationResponse evaluate(EvaluationRequest evaluationRequest) {
 			.call()
 			.content();
 
-		boolean passing = evaluationResponse.equalsIgnoreCase("yes");
+		boolean passing = "yes".equalsIgnoreCase(evaluationResponse);
 		return new EvaluationResponse(passing, "", Collections.emptyMap());
 	}
 
diff --git a/spring-ai-client-chat/src/main/java/org/springframework/ai/chat/evaluation/RelevancyEvaluator.java b/spring-ai-client-chat/src/main/java/org/springframework/ai/chat/evaluation/RelevancyEvaluator.java
index 4f083f8ce76..9de2c181fe0 100644
--- a/spring-ai-client-chat/src/main/java/org/springframework/ai/chat/evaluation/RelevancyEvaluator.java
+++ b/spring-ai-client-chat/src/main/java/org/springframework/ai/chat/evaluation/RelevancyEvaluator.java
@@ -79,7 +79,7 @@ public EvaluationResponse evaluate(EvaluationRequest evaluationRequest) {
 
 		boolean passing = false;
 		float score = 0;
-		if (evaluationResponse != null && evaluationResponse.toLowerCase().contains("yes")) {
+		if ("yes".equalsIgnoreCase(evaluationResponse)) {
 			passing = true;
 			score = 1;
 		}