Open the AI product you use most and write two lines: (1) chat mode model/label (2) advanced/agent mode model/label. If you don't know, check the settings or session info. You're done when you've circled whether they match, plus the one smoke task you'll re-run after any model change, in 12 words or less.
How-to · SEL · SEL.4
Same UI ≠ same model — check the product model id
When a product swaps the model behind the same chat/agent UI, re-run your smoke checks — yesterday's quality and cost no longer apply.
Worked example
Grok's Imagine Agent mode was reported to have quietly switched to Grok 4.5 under the same button (model id: imagine-agent-mode-grok-4-5). The workplace lesson: the label on a button is not a contract with the underlying model. After any silent model swap, re-check one real task you already trust — latency, refusal style, and cost can all shift. You still own publish and send.