diff --git a/langchain4j-mistral-ai/src/main/java/dev/langchain4j/model/mistralai/internal/api/MistralAiChatMessage.java b/langchain4j-mistral-ai/src/main/java/dev/langchain4j/model/mistralai/internal/api/MistralAiChatMessage.java
index 5577b4cf0bc..f7ad01c36ce 100644
--- a/langchain4j-mistral-ai/src/main/java/dev/langchain4j/model/mistralai/internal/api/MistralAiChatMessage.java
+++ b/langchain4j-mistral-ai/src/main/java/dev/langchain4j/model/mistralai/internal/api/MistralAiChatMessage.java
@@ -25,4 +25,5 @@ public class MistralAiChatMessage {
     private String content;
     private String name;
     private List<MistralAiToolCall> toolCalls;
+    private String toolCallId;
 }
diff --git a/langchain4j-mistral-ai/src/main/java/dev/langchain4j/model/mistralai/internal/mapper/MistralAiMapper.java b/langchain4j-mistral-ai/src/main/java/dev/langchain4j/model/mistralai/internal/mapper/MistralAiMapper.java
index 2a84fcc9550..332e2de5929 100644
--- a/langchain4j-mistral-ai/src/main/java/dev/langchain4j/model/mistralai/internal/mapper/MistralAiMapper.java
+++ b/langchain4j-mistral-ai/src/main/java/dev/langchain4j/model/mistralai/internal/mapper/MistralAiMapper.java
@@ -90,6 +90,7 @@ static MistralAiChatMessage toMistralAiMessage(ChatMessage message) {
         if (message instanceof ToolExecutionResultMessage) {
             return MistralAiChatMessage.builder()
                     .role(MistralAiRole.TOOL)
+                    .toolCallId(((ToolExecutionResultMessage) message).id())
                     .name(((ToolExecutionResultMessage) message).toolName())
                     .content(((ToolExecutionResultMessage) message).text())
                     .build();