agentfootprint
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The explainable agent framework — backtrack a wrong answer to the exact context that caused it (evidence, not guesses). Built on footprintjs.
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JavaScript
/**
* coverage — what a run's records are served under, as a typed value with
* THREE states. `undefined` is never "no policy".
*
* Pattern: a closed discriminated union, decided where the library positively
* knows the answer and switched on wherever a record is served.
* Role: the one vocabulary every serving door resolves to
* (`runRedaction.ts` · `coverageOfExecutor`, `declared.ts` ·
* `declarationOf`, `EventDispatcher` · `served`):
*
* - `covered` — the run was opened with a policy: serve under it.
* - `declared-none` — POSITIVELY known to have none: the run was opened by
* this library with no policy, or the runner declared
* none when it was built. Served unchanged.
* - `unknown` — the executor, the run, the scope or the runner is not
* one this library recorded: nothing says what its
* records may show. FAIL CLOSED, whatever the instance
* declares — a placeholder for an event, a refusal for
* a snapshot or a record.
*
* A lookup that misses is `unknown`, never `declared-none`: the difference
* between "this run had no policy" and "this run is not one we know" is the
* difference between serving a record and serving another run's raw values.
*/
/** Positively no policy. */
export const DECLARED_NONE = Object.freeze({ state: 'declared-none' });
/** Not recorded by this library — fail closed. */
export const UNKNOWN_COVERAGE = Object.freeze({ state: 'unknown' });
/**
* The coverage of a run THIS library opened, from the policy it computed for
* the run — the union of typed declarations and the policies handed to the
* run. Here, and only here, an absent policy is a positive fact: every input
* of the union was itself known.
*/
export function coverageOfOpenedRun(policy) {
return policy === undefined ? DECLARED_NONE : Object.freeze({ state: 'covered', policy });
}
/** The policy a coverage serves under — `undefined` for `declared-none` only; `unknown` has none to give. */
export function policyOfCoverage(coverage) {
return coverage.state === 'covered' ? coverage.policy : undefined;
}
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