challenge

<objective> Challenge is the adversarial verification protocol behind the `challenger` agent: refute-by-default, fresh-context intake (claim + evidence only, never the author's reasoning), sources-backed (Context7 -> Exa -> fuse-browser -> code), bounded to 2 refutation rounds ending in a mandatory verdict (CONFIRMED / REFUTED / UNCERTAIN). It is consultative, not a veto -- it reports the strongest objection and leaves the decision to the lead/owner. It fires systematically by claim TYPE, not by a stakes judgment: before a root-cause conclusion, a done/verified claim, an irreversible action (commit/deploy/rm/push), or a 2nd-time fix reaches the owner, whether inside an APEX task or in plain conversation -- plus automatically at every APEX eLicit round and Verify gate. It does not cover code correctness, lint, or type validation -- that stays sniper's lane at eXamine. </objective> # Challenge Skill Reusable protocol behind the `challenger` agent. Also usable directly inside any expert agent's own eLicit step when a dedicated agent call is overkill -- the discipline is the same either way. ## The 7 Principles 1. **Refute by default** -- a claim is FALSE until proven otherwise. Never "are you sure?" -- always a concrete failure scenario + the untested hypothesis it exposes. 2. **Fresh context mandatory** -- intake is the claim + its evidence ONLY, never the author's reasoning. Inheriting the author's angle reproduces the author's blind spot. 3. **Real sources, never memory*...