Skip to main content
Qwen in QitOS is no longer just “JSON-first by default”. For OpenAI-compatible Qwen endpoints, QitOS now prefers this order: 
native tool calls -> Decision.act(...) -> tool execution
fallback: json_decision_v1 -> xml_decision_v1 -> react_text_v1
That matches the spirit of Qwen-Agent: function calling is the preferred lane when the backend exposes it cleanly.

​
What changed in v0.4

The qwen family preset now keeps three ideas together:
  • tool schemas are delivered through api_parameter
  • native tool calls are preferred when the endpoint returns tool_calls
  • text protocols remain available as a stable fallback chain
So the default protocol is still json_decision_v1, but for Qwen it is now the text fallback, not the ideal path itself.

​
When the native lane is used

QitOS will prefer the native lane when all of these are true:
  • the model resolves to the qwen family preset
  • the harness metadata says native_tool_call_preferred = true
  • the OpenAI-compatible response actually contains tool_calls
If any of those conditions fail, QitOS falls back to the normal parser chain.

​
Why QitOS does not copy the Qwen-Agent sentinel prompt

The official Qwen-Agent project includes a Qwen-specific function-calling prompt format for chat interfaces that do not provide a native tool channel. QitOS does not copy that prompt format directly for the OpenAI-compatible Qwen path because:
  • OpenAI-compatible serving already gives us a structured tool_calls channel
  • preserving that structure is cleaner than serializing it back into text
  • it keeps the runtime generic enough for other families that also expose native tool calls
In other words:
  • Qwen-Agent solves the more general “Qwen chat interface” problem
  • QitOS solves the “OpenAI-compatible served Qwen inside one reusable harness layer” problem
Use the flagship example with an OpenAI-compatible Qwen endpoint: 
export OPENAI_API_KEY="your_api_key"
export OPENAI_BASE_URL="https://dashscope.aliyuncs.com/compatible-mode/v1"

python examples/real/claude_code_agent.py \
  --model-family qwen \
  --model-name qwen-plus \
  --print-harness
You should expect the harness summary to show:
  • family_preset: qwen
  • tool_delivery: api_parameter
  • native_tool_call_preferred: True
  • decision_lane_preference: native_tool_calls

​
How to confirm it in qita

Inspect the run in qita and check:
  • family preset
  • prompt protocol
  • tool delivery
  • decision_source
  • native_tool_call_used
  • native_tool_call_fallback_reason
If the endpoint did not return native tool calls, QitOS will still run, but you should see the fallback reason and the parser lane in the trace.