# Understand plans, answers, and provenance

A Cassis answer is inspectable. Check the plan for assumptions, the SQL for execution, and the ontology objects for provenance.

## Check the plan

The plan is Cassis’s interpretation of the question. Read its assumptions first: “revenue last quarter” may mean booked revenue, calendar quarter, excluding refunds.

When Cassis surfaces a plan for approval, nothing runs until you approve it. Plans without a genuine fork run automatically. If an assumption is wrong, state the correction; you do not need to rewrite the whole question.

## Check the answer

- **Answer** The conclusion and numbers, in the language you used.

- **SQL** The exact generated statement. On a connected warehouse it produced the rows; on a schema-only project it was not executed and `results` is `null`.

- **Objects used** The tables, joins, and metrics that grounded the answer. An unexpected object is a reason to inspect the result more closely.

- **Ontology version** The published context the conversation is using. Follow-ups stay in the same conversation and keep that context.

## Correct a wrong answer

Rate it down and explain the missing or incorrect rule in the conversation. The correction becomes evidence; recurring evidence is grouped into a [detected issue](/curate/issues/) for the data team.

In the web app, **Add as test case** captures a candidate regression case. A reviewer must validate both the SQL and the business interpretation before it becomes approved truth.

**“Not answerable” is useful.** It means the required definition, relationship, or data is missing. Clarify the question if the intent was different; otherwise send the gap to the people maintaining the ontology instead of retrying unchanged.