What "deterministic" means here
Every control in the OXXON Audit rule library is a fixed, disclosed test against the workbook's parsed structure and formula dependency graph — not a probabilistic judgement made by a language model. Given the same workbook, the engine produces the same findings, the same score, and the same grade, on every run, on every machine.
Findings are rendered from static narrative text tied to the rule that fired, not generated free-form per run. The same structural problem is described in identical language every time it is found, in any workbook.
Rule independence
The 26 structural controls are independent of one another: each tests a distinct structural condition. A workbook is tested against all 26 regardless of what any other rule finds — coverage is total, not adaptive or short-circuited.
What stays private
The rule categories and their philosophy are public. The specific tolerances, thresholds, and the internal test corpus are not published — that detail is the moat. This is the same boundary a testing standard publishes its criteria without publishing its answer key.