diff --git a/api/src/main/java/com/theokanning/openai/completion/chat/AssistantMessage.java b/api/src/main/java/com/theokanning/openai/completion/chat/AssistantMessage.java
index b3c00a0..a0ebcc8 100644
--- a/api/src/main/java/com/theokanning/openai/completion/chat/AssistantMessage.java
+++ b/api/src/main/java/com/theokanning/openai/completion/chat/AssistantMessage.java
@@ -22,6 +22,10 @@ public class AssistantMessage implements ChatMessage {
     // The contents of the assistant message. Required unless tool_calls or function_call is specified.
     String content;
 
+    // The contents of the reasoning message. 
+    @JsonProperty("reasoning_content")
+    String reasoningContent;
+
     //An optional name for the participant. Provides the model information to differentiate between participants of the same role.
     String name;