"Assays value, never advises."
The invariant, and why it is first
Architecture documents in this family open with a list of invariants — the properties that must hold no matter what gets built later. Touchstone's first one is four words long: assays value, never advises. Everything automatic that the product shows is descriptive: the value, its date, its source, and its percentile context. No rankings. No buy or sell framing. No alert engineered to provoke action.
Putting it first is deliberate. An invariant that arrives on page four gets read as a preference. An invariant that arrives before the system context table gets read as a constraint on everything below it — which is what it actually is, because every feature proposal after that point has to pass through it.
What makes it enforceable rather than aspirational
Plenty of products have a sentence like this in a design doc and violate it by the third sprint, because a sentence in a document cannot stop a pull request. Two things make this one hold.
The first is that it is stated as a review test, not as a value: enforced by review of every new surface against this sentence. That converts an abstract ethic into a concrete question with a yes-or-no answer — does this new card rank anything? does it use urgency language? does it imply a forecast? A question you can actually ask about a diff is worth ten paragraphs of principle.
The second is that the sentence has teeth in the code. You will see functions in this quest that could easily have returned a signal and deliberately do not: a regime classifier that returns a phrase like ELEVATED instead of a score-to-act-on, a change digest whose own docstring says ordering is an ordering, never a ranking of importance. The discipline is written where it can be read by the next person to touch the file.
The line is initiation, not silence
An important subtlety, inherited from the portfolio sibling: this is not a rule that the software must be useless when asked a real question. The boundary sits between unsolicited and requested. Every surface the app renders on its own stays strictly descriptive. When a human deliberately opens the assistant surface and asks a direct question, they get ordinary judgment, because they initiated it.
That distinction is what keeps the rule from collapsing into disclaimer theater. A tool that constantly volunteers advice is a nag. A tool that refuses to answer a direct question is merely broken, and usually gets replaced by something worse. The restraint belongs on the automatic surface, where nobody asked.