Architect

May 14, 2025 · Artificial Intelligence

How Qwen3 Controls Hybrid Reasoning with the enable_thinking Parameter

This article explains how Qwen3 implements hybrid (fast/slow) reasoning by using the enable_thinking flag in the tokenizer's apply_chat_template method, detailing the underlying Jinja2 chat template, example prompts, the effect of toggling the flag, and design considerations for future autonomous thinking control.