Reasoning models stating thinking depth as "undefined"

When starting a new thread on t3chat via URL of any thinking model, the resulting response will use a thinking depth of “undefined”.

This occurs on any of the following models:
- o4 mini
- o3 mini
- Gemini 2.5 Flash (Thinking)
- Grok 3 mini
- Claude 3.7 Sonnet (Thinking)

Example:

https://t3.chat/new?model=gemini-2.5-flash-thinking&q=what day is today
Model information below response would then say:

“Generated with Gemini 2.5 Flash (Thinking) (undefined)”