Capstone 86 — Constitutional Rules Engine
A rule is a name, a predicate, and an explanation. Anything missing one of those three is a vibe, not a rule. Classifiers cover the recognizable failures. Rules engines cover the contractual ones. A team writing a coding assistant wants a constraint like "every response that contains code must end in either a runnable block or a stated assumption." A team running a customer support bot wants "every refusal must offer a next step." These constraints are not natural classifier targets. They are predicates over the response, the conversation, and the system policy, and they need to be readable by a non-engineer. The honest representation is a declarative file. A constitution lives in YAML alongside the code, in version control, with a separate review process. Each rule has a name, a predicate, a severity, and an explanation template. The engine loads the file, evaluates each rule against the candidate output, and returns a structured Violation per rule that fired. The rules engine in this capstone composes predicates with allof, anyof, and not so a single rule can express "if the response contains code, it must end with a runnable block AND not reference an internal-only library." The other half of the lesson is revision. A rule engine that only blocks is half-built. A rule engine that proposes a fix is…
Capstone 86 — Constitutional Rules Engine: A rule is a name, a predicate, and an explanation. Anything missing one of those three is a vibe, not a rule.
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