Platform freshness (V17 Wave A). 518 tests.
New hook: SubagentStop -- tailtest now fires after a subagent finishes its work, not just after direct Claude edits. Files queued in pending_files during a subagent's tool calls are surfaced to the parent turn via an additionalContext drain note, so subagent-authored code is no longer silently skipped.
New agent: agents/verifier.md -- a read-only haiku-powered failure triage agent. Auto-invoked on test failures, it classifies each failure as real-bug | wrong-test | flaky | env and returns a one-line root cause to the main thread without modifying any files.
Plugin manifest polish -- .claude-plugin/plugin.json now declares displayName, enriched keywords (adds tdd, adversarial), agents reference, hooks path, and typed userConfig for depth. Enables marketplace display name and config UI.