Definition
The degree to which a brand is mentioned and cited in AI answers.
Why it matters
It is the first metric in the chain. Content, schema and distribution work is only worth funding if you can tell whether it moved this number, on the same questions, measured the same way.
How to measure it
Mention rate over a fixed question set, reported per engine, with unmeasured cells excluded rather than counted as zero, and questions containing the brand name excluded from scoring.