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 ## Status
 
+M3 (drift interceptor): while a commitment is Active, the daemon watches the
+focused window. A cheap local match against the session's allowed window classes
+is authoritative for on-task; only unmatched windows are sent to the LLM drift
+judge (debounced and cached per class, run asynchronously). When it judges you
+off-task, the active view shows a dismissible interrupt: "Back to task", "This is
+on task" (which adds the app to the session's allowed list), or "End session".
+The drift judge degrades gracefully — without it, local matching still runs.
+
 M2 (AI planning coach): in the Planning view, a rough intent is "sharpened"
 into a structured commitment (next action, success condition, timebox) by an
 LLM CLI backend (claude or codex, selectable via `ANTIDRIFT_AI_BACKEND`). The