diff --git a/spring-ai-model/src/test/java/org/springframework/ai/tool/execution/DefaultToolCallResultConverterTests.java b/spring-ai-model/src/test/java/org/springframework/ai/tool/execution/DefaultToolCallResultConverterTests.java
index 5b1e908fe48..a7c5288fdb0 100644
--- a/spring-ai-model/src/test/java/org/springframework/ai/tool/execution/DefaultToolCallResultConverterTests.java
+++ b/spring-ai-model/src/test/java/org/springframework/ai/tool/execution/DefaultToolCallResultConverterTests.java
@@ -123,6 +123,37 @@ void convertImageShouldReturnBase64Image() throws IOException {
 		assertThat(imgRes.getRGB(0, 0)).isEqualTo(img.getRGB(0, 0));
 	}
 
+	@Test
+	void convertEmptyCollectionsShouldReturnEmptyJson() {
+		assertThat(this.converter.convert(List.of(), List.class)).isEqualTo("[]");
+		assertThat(this.converter.convert(Map.of(), Map.class)).isEqualTo("{}");
+		assertThat(this.converter.convert(new String[0], String[].class)).isEqualTo("[]");
+	}
+
+	@Test
+	void convertRecordReturnTypeShouldReturnJson() {
+		TestRecord record = new TestRecord("recordName", 1);
+		String result = this.converter.convert(record, TestRecord.class);
+
+		assertThat(result).containsIgnoringWhitespaces("\"recordName\"");
+		assertThat(result).containsIgnoringWhitespaces("1");
+	}
+
+	@Test
+	void convertSpecialCharactersInStringsShouldEscapeJson() {
+		String specialChars = "Test with \"quotes\", newlines\n, tabs\t, and backslashes\\";
+		String result = this.converter.convert(specialChars, String.class);
+
+		// Should properly escape JSON special characters
+		assertThat(result).contains("\\\"quotes\\\"");
+		assertThat(result).contains("\\n");
+		assertThat(result).contains("\\t");
+		assertThat(result).contains("\\\\");
+	}
+
+	record TestRecord(String name, int value) {
+	}
+
 	record Base64Wrapper(MimeType mimeType, String data) {
 	}
 
diff --git a/vector-stores/spring-ai-redis-store/src/test/java/org/springframework/ai/vectorstore/redis/RedisFilterExpressionConverterTests.java b/vector-stores/spring-ai-redis-store/src/test/java/org/springframework/ai/vectorstore/redis/RedisFilterExpressionConverterTests.java
index 33ae76edf8c..732013161ae 100644
--- a/vector-stores/spring-ai-redis-store/src/test/java/org/springframework/ai/vectorstore/redis/RedisFilterExpressionConverterTests.java
+++ b/vector-stores/spring-ai-redis-store/src/test/java/org/springframework/ai/vectorstore/redis/RedisFilterExpressionConverterTests.java
@@ -129,4 +129,46 @@ void testComplexIdentifiers() {
 		assertThat(vectorExpr).isEqualTo("@'country 1 2 3':{BG}");
 	}
 
+	@Test
+	void testSpecialCharactersInValues() {
+		// Test values with Redis special characters that need escaping
+		String vectorExpr = converter(RedisVectorStore.MetadataField.tag("description"))
+			.convertExpression(new Expression(EQ, new Key("description"), new Value("test@value{with}special|chars")));
+
+		// Should properly escape special Redis characters
+		assertThat(vectorExpr).isEqualTo("@description:{test@value{with}special|chars}");
+	}
+
+	@Test
+	void testEmptyStringValues() {
+		String vectorExpr = converter(RedisVectorStore.MetadataField.tag("status"))
+			.convertExpression(new Expression(EQ, new Key("status"), new Value("")));
+
+		assertThat(vectorExpr).isEqualTo("@status:{}");
+	}
+
+	@Test
+	void testSingleItemInList() {
+		String vectorExpr = converter(RedisVectorStore.MetadataField.tag("status"))
+			.convertExpression(new Expression(IN, new Key("status"), new Value(List.of("active"))));
+
+		assertThat(vectorExpr).isEqualTo("@status:{active}");
+	}
+
+	@Test
+	void testWhitespaceInFieldNames() {
+		String vectorExpr = converter(RedisVectorStore.MetadataField.tag("value with spaces"))
+			.convertExpression(new Expression(EQ, new Key("\"value with spaces\""), new Value("test")));
+
+		assertThat(vectorExpr).isEqualTo("@\"value with spaces\":{test}");
+	}
+
+	@Test
+	void testNestedQuotedFieldNames() {
+		String vectorExpr = converter(RedisVectorStore.MetadataField.tag("value \"with\" quotes"))
+			.convertExpression(new Expression(EQ, new Key("\"value \\\"with\\\" quotes\""), new Value("test")));
+
+		assertThat(vectorExpr).isEqualTo("@\"value \\\"with\\\" quotes\":{test}");
+	}
+
 }