fix(ai): preserve qwen chat-template thinking closes #3325

packages/ai/CHANGELOG.md

@@ -5,6 +5,7 @@
 ### Fixed
 
 - Fixed Anthropic and Bedrock adaptive-thinking payload tests to expect the default `display: "summarized"` field when reasoning is enabled.
+- Fixed `qwen-chat-template` OpenAI-compatible requests to set `chat_template_kwargs.preserve_thinking: true`, preserving prior Qwen thinking across turns so multi-turn tool calls keep their arguments instead of degrading to empty `{}` payloads ([#3325](https://github.com/badlogic/pi-mono/issues/3325))
 
 ## [0.67.6] - 2026-04-16
 

packages/ai/src/providers/openai-completions.ts

@@ -422,7 +422,10 @@ function buildParams(model: Model<"openai-completions">, context: Context, optio
 	} else if (compat.thinkingFormat === "qwen" && model.reasoning) {
 		(params as any).enable_thinking = !!options?.reasoningEffort;
 	} else if (compat.thinkingFormat === "qwen-chat-template" && model.reasoning) {
-		(params as any).chat_template_kwargs = { enable_thinking: !!options?.reasoningEffort };
+		(params as any).chat_template_kwargs = {
+			enable_thinking: !!options?.reasoningEffort,
+			preserve_thinking: true,
+		};
 	} else if (compat.thinkingFormat === "openrouter" && model.reasoning) {
 		// OpenRouter normalizes reasoning across providers via a nested reasoning object.
 		const openRouterParams = params as typeof params & { reasoning?: { effort?: string } };