fix: [Orchestration] tool calling works on all models (#578)

* fix: [Orchestration] tool calling works on all models

* release notes

* fix test

* PMD

* withToolCalls

---------

Co-authored-by: Alexander Dümont <[email protected]>

Author: CharlesDuboisSAP

docs/release_notes.md

@@ -20,4 +20,4 @@
 
 ### 🐛 Fixed Issues
 
--
+- [Orchestration] Tool calling works on all models

orchestration/src/main/java/com/sap/ai/sdk/orchestration/AssistantMessage.java

@@ -8,6 +8,7 @@
 import com.sap.ai.sdk.orchestration.model.ChatMessageContent;
 import com.sap.ai.sdk.orchestration.model.MessageToolCall;
 import com.sap.ai.sdk.orchestration.model.TextContent;
+import java.util.ArrayList;
 import java.util.List;
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
@@ -57,30 +58,55 @@ public AssistantMessage(@Nonnull final String singleMessage) {
    * Creates a new assistant message with the given tool calls.
    *
    * @param toolCalls list of tool call objects
+   * @deprecated Please use {@link #withToolCalls(List)} instead.
    */
+  @Deprecated
   public AssistantMessage(@Nonnull final List<MessageToolCall> toolCalls) {
     content = new MessageContent(List.of());
     this.toolCalls = toolCalls;
   }
 
+  private AssistantMessage(
+      @Nonnull final MessageContent content, @Nullable final List<MessageToolCall> toolCalls) {
+    this.content = content;
+    this.toolCalls = toolCalls;
+  }
+
+  /**
+   * Returns a new AssistantMessage instance with the provided tool calls added to the existing
+   * ones.
+   *
+   * @param toolCalls the list of tool calls to add.
+   * @return a new AssistantMessage instance with the combined tool calls.
+   */
+  @Nonnull
+  public AssistantMessage withToolCalls(@Nonnull final List<MessageToolCall> toolCalls) {
+    val newToolcalls = new ArrayList<>(this.toolCalls != null ? this.toolCalls : List.of());
+    newToolcalls.addAll(toolCalls);
+    return new AssistantMessage(this.content, newToolcalls);
+  }
+
   @Nonnull
   @Override
   public ChatMessage createChatMessage() {
+    val assistantChatMessage = AssistantChatMessage.create().role(ASSISTANT);
+
     if (toolCalls != null) {
-      return AssistantChatMessage.create().role(ASSISTANT).toolCalls(toolCalls);
+      assistantChatMessage.setToolCalls(toolCalls);
     }
+
+    ChatMessageContent text;
     if (content.items().size() == 1 && content.items().get(0) instanceof TextItem textItem) {
-      return AssistantChatMessage.create()
-          .role(ASSISTANT)
-          .content(ChatMessageContent.create(textItem.text()));
+      text = ChatMessageContent.create(textItem.text());
+    } else {
+      val texts =
+          content.items().stream()
+              .filter(item -> item instanceof TextItem)
+              .map(item -> (TextItem) item)
+              .map(item -> TextContent.create().type(TextContent.TypeEnum.TEXT).text(item.text()))
+              .toList();
+      text = ChatMessageContent.create(texts);
     }
-    val texts =
-        content.items().stream()
-            .filter(item -> item instanceof TextItem)
-            .map(item -> (TextItem) item)
-            .map(item -> TextContent.create().type(TextContent.TypeEnum.TEXT).text(item.text()))
-            .toList();
-
-    return AssistantChatMessage.create().role(ASSISTANT).content(ChatMessageContent.create(texts));
+    return assistantChatMessage.content(text);
   }
 }

orchestration/src/main/java/com/sap/ai/sdk/orchestration/spring/OrchestrationChatModel.java

@@ -126,16 +126,17 @@ private static com.sap.ai.sdk.orchestration.Message[] toOrchestrationMessages(
               case USER:
                 yield List.of(new UserMessage(msg.getText()));
               case ASSISTANT:
+                val assistantMessage = new AssistantMessage(msg.getText());
                 val springToolCalls =
                     ((org.springframework.ai.chat.messages.AssistantMessage) msg).getToolCalls();
                 if (springToolCalls != null && !springToolCalls.isEmpty()) {
                   final List<MessageToolCall> sdkToolCalls =
                       springToolCalls.stream()
                           .map(OrchestrationChatModel::toOrchestrationToolCall)
                           .toList();
-                  yield List.of(new AssistantMessage(sdkToolCalls));
+                  yield List.of(assistantMessage.withToolCalls(sdkToolCalls));
                 }
-                yield List.of(new AssistantMessage(msg.getText()));
+                yield List.of(assistantMessage);
               case TOOL:
                 val toolResponses = ((ToolResponseMessage) msg).getResponses();
                 yield toolResponses.stream()

orchestration/src/test/resources/toolCallsRequest2.json

@@ -17,6 +17,7 @@
             },
             {
               "role": "assistant",
+              "content" : "",
               "tool_calls": [
                 {
                   "id": "call_LOyP7EVdeqFlGEmVzmPdCVey",