[9.2] [Bug][Inference chat model] Fix format for parallel tool call results. Consecutive tool results need to be merged into a single message (#241103) (#241389)

kibanamachine · KDKHD · elasticmachine · web-flow · commit 99b0758e6736 · 2025-10-31T01:52:25.000+01:00
# Backport This will backport the following commits from `main` to `9.2`: - [[Bug][Inference chat model] Fix format for parallel tool call results. Consecutive tool results need to be merged into a single message (#241103)](#241103)  ### Questions ? Please refer to the [Backport tool documentation](https://github.com/sorenlouv/backport)  Co-authored-by: Kenneth Kreindler <42113355+KDKHD@users.noreply.github.com> Co-authored-by: Elastic Machine <elasticmachine@users.noreply.github.com> Co-authored-by: Quynh Nguyen <quynh.nguyen@elastic.co>
diff --git a/x-pack/platform/plugins/shared/inference/server/chat_complete/adapters/bedrock/bedrock_claude_adapter.test.ts b/x-pack/platform/plugins/shared/inference/server/chat_complete/adapters/bedrock/bedrock_claude_adapter.test.ts
@@ -236,6 +236,146 @@ Human:`,
       ]);
     });
 
+    it('correctly format consecutive tool result messages', () => {
+      bedrockClaudeAdapter
+        .chatComplete({
+          executor: executorMock,
+          logger,
+          messages: [
+            {
+              role: MessageRole.User,
+              content: 'question',
+            },
+            {
+              role: MessageRole.Assistant,
+              content: 'answer',
+            },
+            {
+              role: MessageRole.User,
+              content: 'another question',
+            },
+            {
+              role: MessageRole.Assistant,
+              content: null,
+              toolCalls: [
+                {
+                  function: {
+                    name: 'my_function',
+                    arguments: {
+                      foo: 'bar',
+                    },
+                  },
+                  toolCallId: '0',
+                },
+                {
+                  function: {
+                    name: 'my_other_function',
+                    arguments: {
+                      baz: 'qux',
+                    },
+                  },
+                  toolCallId: '1',
+                },
+              ],
+            },
+            {
+              name: 'my_function',
+              role: MessageRole.Tool,
+              toolCallId: '0',
+              response: {
+                bar: 'foo',
+              },
+            },
+            {
+              name: 'my_other_function',
+              role: MessageRole.Tool,
+              toolCallId: '1',
+              response: {
+                qux: 'baz',
+              },
+            },
+            {
+              role: MessageRole.Assistant,
+              content: null,
+              toolCalls: [
+                {
+                  function: {
+                    name: 'my_function_2',
+                    arguments: {
+                      foo: 'bar',
+                    },
+                  },
+                  toolCallId: '2',
+                },
+                {
+                  function: {
+                    name: 'my_other_function_2',
+                    arguments: {
+                      baz: 'qux',
+                    },
+                  },
+                  toolCallId: '3',
+                },
+              ],
+            },
+            {
+              name: 'my_function_2',
+              role: MessageRole.Tool,
+              toolCallId: '2',
+              response: {
+                bar: 'foo',
+              },
+            },
+            {
+              name: 'my_other_function_2',
+              role: MessageRole.Tool,
+              toolCallId: '3',
+              response: {
+                qux: 'baz',
+              },
+            },
+          ],
+        })
+        .subscribe(noop);
+
+      expect(executorMock.invoke).toHaveBeenCalledTimes(1);
+
+      const { messages } = getCallParams();
+      expect(messages).toEqual([
+        { role: 'user', content: [{ text: 'question' }] },
+        { role: 'assistant', content: [{ text: 'answer' }] },
+        { role: 'user', content: [{ text: 'another question' }] },
+        {
+          role: 'assistant',
+          content: [
+            { toolUse: { toolUseId: '0', name: 'my_function', input: { foo: 'bar' } } },
+            { toolUse: { toolUseId: '1', name: 'my_other_function', input: { baz: 'qux' } } },
+          ],
+        },
+        {
+          role: 'user',
+          content: [
+            { toolResult: { toolUseId: '0', content: [{ json: { bar: 'foo' } }] } },
+            { toolResult: { toolUseId: '1', content: [{ json: { qux: 'baz' } }] } },
+          ],
+        },
+        {
+          role: 'assistant',
+          content: [
+            { toolUse: { toolUseId: '2', name: 'my_function_2', input: { foo: 'bar' } } },
+            { toolUse: { toolUseId: '3', name: 'my_other_function_2', input: { baz: 'qux' } } },
+          ],
+        },
+        {
+          role: 'user',
+          content: [
+            { toolResult: { toolUseId: '2', content: [{ json: { bar: 'foo' } }] } },
+            { toolResult: { toolUseId: '3', content: [{ json: { qux: 'baz' } }] } },
+          ],
+        },
+      ]);
+    });
+
     it('correctly format system message', () => {
       bedrockClaudeAdapter
         .chatComplete({
diff --git a/x-pack/platform/plugins/shared/inference/server/chat_complete/adapters/bedrock/bedrock_claude_adapter.ts b/x-pack/platform/plugins/shared/inference/server/chat_complete/adapters/bedrock/bedrock_claude_adapter.ts
@@ -96,7 +96,7 @@ export const bedrockClaudeAdapter: InferenceConnectorAdapter = {
 };
 
 const messagesToBedrock = (messages: Message[]): BedRockMessage[] => {
-  return messages.map((message): BedRockMessage => {
+  const converseMessages: BedRockMessage[] = messages.map((message): BedRockMessage => {
     switch (message.role) {
       case MessageRole.User: {
         const rawContent: BedRockMessage['rawContent'] = [];
@@ -180,4 +180,25 @@ const messagesToBedrock = (messages: Message[]): BedRockMessage[] => {
       }
     }
   });
+
+  // Combine consecutive user tool result messages into a single message. This format is required by Bedrock.
+  const combinedConverseMessages = converseMessages.reduce<BedRockMessage[]>((acc, curr) => {
+    const lastMessage = acc[acc.length - 1];
+
+    if (
+      lastMessage &&
+      lastMessage.role === 'user' &&
+      lastMessage.rawContent?.some((c) => 'toolResult' in c) &&
+      curr.role === 'user' &&
+      curr.rawContent?.some((c) => 'toolResult' in c)
+    ) {
+      lastMessage.rawContent = lastMessage.rawContent.concat(curr.rawContent);
+    } else {
+      acc.push(curr);
+    }
+
+    return acc;
+  }, []);
+
+  return combinedConverseMessages;
 };
