From e5ed6b833ff231ac6ef2e4102bf0c6f9038a5080 Mon Sep 17 00:00:00 2001
From: YuanHanzhong <YuanHanzhong@users.noreply.github.com>
Date: Mon, 18 May 2026 22:02:37 +0800
Subject: [PATCH] fix(core): mirror Qwen reasoning history field

---
 .../provider/default.test.ts                  | 38 +++++++++++++++
 .../provider/default.ts                       | 46 ++++++++++++++++++-
 2 files changed, 83 insertions(+), 1 deletion(-)

diff --git a/packages/core/src/core/openaiContentGenerator/provider/default.test.ts b/packages/core/src/core/openaiContentGenerator/provider/default.test.ts
index 12c04c115c..5b1b1c542d 100644
--- a/packages/core/src/core/openaiContentGenerator/provider/default.test.ts
+++ b/packages/core/src/core/openaiContentGenerator/provider/default.test.ts
@@ -409,6 +409,44 @@ describe('DefaultOpenAICompatibleProvider', () => {
       });
     });
 
+    it('should mirror reasoning_content to reasoning for Qwen model history', () => {
+      const qwenProvider = new DefaultOpenAICompatibleProvider(
+        {
+          ...mockContentGeneratorConfig,
+          model: 'Qwen/Qwen3.6-35B-A3B',
+        } as ContentGeneratorConfig,
+        mockCliConfig,
+      );
+      const originalRequest: OpenAI.Chat.ChatCompletionCreateParams = {
+        model: 'Qwen/Qwen3.6-35B-A3B',
+        messages: [
+          {
+            role: 'assistant',
+            content: 'The answer.',
+            reasoning_content: 'Prior reasoning.',
+          } as OpenAI.Chat.ChatCompletionAssistantMessageParam & {
+            reasoning_content: string;
+          },
+        ],
+      };
+
+      const result = qwenProvider.buildRequest(originalRequest, 'prompt-id');
+      const assistant = result.messages[0] as
+        | OpenAI.Chat.ChatCompletionAssistantMessageParam
+        | (OpenAI.Chat.ChatCompletionAssistantMessageParam & {
+            reasoning_content?: string;
+            reasoning?: string;
+          });
+
+      expect(assistant).toEqual(
+        expect.objectContaining({
+          reasoning_content: 'Prior reasoning.',
+          reasoning: 'Prior reasoning.',
+        }),
+      );
+      expect(originalRequest.messages[0]).not.toHaveProperty('reasoning');
+    });
+
     it('should not include extra_body when not configured', () => {
       const originalRequest: OpenAI.Chat.ChatCompletionCreateParams = {
         model: 'gpt-4',
diff --git a/packages/core/src/core/openaiContentGenerator/provider/default.ts b/packages/core/src/core/openaiContentGenerator/provider/default.ts
index 891188dcd1..ace2fae093 100644
--- a/packages/core/src/core/openaiContentGenerator/provider/default.ts
+++ b/packages/core/src/core/openaiContentGenerator/provider/default.ts
@@ -11,6 +11,8 @@ import {
   hasExplicitOutputLimit,
 } from '../../tokenLimits.js';
 
+const QWEN_MODEL_MARKER = 'qwen';
+
 /**
  * Default provider for standard OpenAI-compatible APIs
  */
@@ -76,10 +78,11 @@ export class DefaultOpenAICompatibleProvider
     // This prevents occupying too much context window with output reservation
     const requestWithTokenLimits = this.applyOutputTokenLimit(request);
 
-    return {
+    const builtRequest = {
       ...requestWithTokenLimits,
       ...(extraBody ? extraBody : {}),
     };
+    return this.mirrorQwenReasoningContent(builtRequest);
   }
 
   getDefaultGenerationConfig(): GenerateContentConfig {
@@ -167,4 +170,45 @@ export class DefaultOpenAICompatibleProvider
       max_tokens: effectiveMaxTokens,
     };
   }
+
+  private mirrorQwenReasoningContent(
+    request: OpenAI.Chat.ChatCompletionCreateParams,
+  ): OpenAI.Chat.ChatCompletionCreateParams {
+    const model = request.model.toLowerCase();
+    if (!model.includes(QWEN_MODEL_MARKER)) {
+      return request;
+    }
+
+    let changed = false;
+    const messages = request.messages.map((message) => {
+      if (message.role !== 'assistant') {
+        return message;
+      }
+
+      const extended = message as unknown as Record<string, unknown>;
+      const reasoningContent = extended['reasoning_content'];
+      if (
+        typeof reasoningContent !== 'string' ||
+        reasoningContent.length === 0 ||
+        typeof extended['reasoning'] === 'string'
+      ) {
+        return message;
+      }
+
+      changed = true;
+      return {
+        ...extended,
+        reasoning: reasoningContent,
+      } as unknown as OpenAI.Chat.ChatCompletionMessageParam;
+    });
+
+    if (!changed) {
+      return request;
+    }
+
+    return {
+      ...request,
+      messages,
+    };
+  }
 }