Tool contract 6.0.0

The leaked-elixir counter travels as one object with its caveat on the value (feedback #65 and #66, 2026-09-19). The 3.13.0 note beside the row was served, read and overridden by a consuming agent the morning it shipped, because the number sat beside crowns and trophy_change as if it were an outcome fact; and the differential was populated on duel rows where the shipped spec said null, which supplied the exact number that agent misused. Jamie's call: keep the fields, move them under one object that carries the caveat itself.

• battles_query full verbosity: me.elixir and every teammate's and opponent's elixir is { leaked, opponent_leaked, differential, rounds, caveat } or null when the game did not report it. leaked is the side's own counter; opponent_leaked the one opponent's on me of a head-to-head row (null on 2v2 and always null on teammates and opponents); differential is leaked minus opponent_leaked on a single-game head-to-head row and NULL on every duel (each side's counter sums two or three games played on different decks); rounds is how many games the counters sum over (null on a duel whose rounds the record never held); caveat says why none of it is a skill measure.
• The duel note names the field: elixir.leaked sums across rounds for both sides.
• verbosity is accepted on every tool. The instructions call it the one size control without listing tools, so agents sent it everywhere and forty-three tools refused it. A tool with one size now accepts full or compact, answers in full, echoes applied.verbosity: "full" and, when compact was asked, says in a note that it had nothing to drop. The eleven tools that declare it are unchanged.
• elixir_send_feedback.message takes 8,000 characters (was 4,000), and every string-length refusal says how long the value was (must be at most 8000 characters; it is 9,214), so nobody trims blind (feedback #64).

No deprecation window (first-party clients; the 3.0.0, 4.0.0 and 5.0.0 precedent). This is the last major before the adoption freeze: additive minors only from here.