Describe the symptom
A phrase matcher recognizes fixtures, behaviours, and relationships—such as a bathtub reacting when a toilet flushes.
The next useful question,
not a giant questionnaire.
HomeSOS uses transparent, deterministic reasoning to narrow possible causes while keeping safety rules separate and conservative.
Screen for danger
Gas, carbon monoxide, smoke, electrical arcing, structural instability, and water near electricity stop normal diagnosis.
Answer adaptive questions
Each answer changes the estimated likelihoods. The engine selects a question that best separates the remaining causes.
Get an honest result
You see the likely cause, uncertainty, urgency, safe next step, costs, and guided DIY only when the risk boundary allows it.
What confidence means
HomeSOS confidence is an estimated likelihood from the selected diagnostic rules and your answers. It is not a scientific measurement, guarantee, or substitute for an onsite inspection. When evidence does not clearly separate two causes, HomeSOS says so.
What happens when you choose “I don't know”?
The engine can explain a safe way to identify the observation, ask an easier question, use different evidence, or return a narrowed result. Unknown answers never break the flow.