Function validateDecide

lib/gstack-decision.ts:103–164

(input: Partial<DecisionEvent>)

 *  - a HIGH-tier secret (redact engine) in any free-text field.
 */
export function validateDecide(input: Partial<DecisionEvent>): ValidateResult {
  if (!input.decision || typeof input.decision !== "string" || !input.decision.trim()) {
    return { ok: false, error: "decision text is required" };
  }
  const scope = input.scope ?? "repo";
  if (!DECISION_SCOPES.includes(scope)) {
    return { ok: false, error: `invalid scope "${scope}"; must be ${DECISION_SCOPES.join("|")}` };
  }
  const source = input.source ?? "agent";
  if (!DECISION_SOURCES.includes(source)) {
    return { ok: false, error: `invalid source "${source}"; must be ${DECISION_SOURCES.join("|")}` };
  }
  if (input.confidence !== undefined) {
    const c = Number(input.confidence);
    if (!Number.isInteger(c) || c < 1 || c > 10) {
      return { ok: false, error: "confidence must be integer 1-10" };
    }
  }

  // Scan ALL stored free-text — incl. branch/issue, which are surfaced (and emitted raw
  // via --json), so they must not carry secrets or injection either (Codex finding).
  const freeText = [input.decision, input.rationale, input.alternatives_considered, input.branch, input.issue]
    .filter((s): s is string => typeof s === "string")
    .join("\n");

  if (hasInjection(freeText)) {
    return { ok: false, error: "decision contains instruction-like content (injection), rejected" };
  }
  const redacted = scan(freeText);
  if (redacted.counts.HIGH > 0) {
    return {
      ok: false,
      error: `decision contains a HIGH-tier secret (${redacted.counts.HIGH} finding(s)); rotate + remove it, do not log secrets`,
    };
  }
  // MEDIUM = PII / credential-shaped content. The taxonomy says "confirm via
  // AskUserQuestion", but this store is NON-INTERACTIVE and syncs cross-machine,
  // so there is no confirm path — fail closed rather than silently persist + sync a
  // secret that later resurfaces into agent context.
  if (redacted.counts.MEDIUM > 0) {
    return {
      ok: false,
      error: `decision contains MEDIUM-tier sensitive content (${redacted.counts.MEDIUM} finding(s): PII or credential-shaped). This store is non-interactive and syncs across machines, so it fails closed — remove or rephrase the value before logging.`,
    };
  }

  const event: DecisionEvent = {
    id: input.id || randomUUID(),
    kind: "decide",
    decision: input.decision.trim(),
    rationale: input.rationale,
    alternatives_considered: input.alternatives_considered,
    scope,
    branch: input.branch || undefined,
    issue: input.issue || undefined,
    date: input.date || new Date().toISOString(),
    session: input.session,
    source,