Discovery Feed

Novel-coupling feed produced by the 6 discovery detectors.

• active_couplings: feature pairs whose mutual information exceeds baseline by >=2 sigma, deduped, with first/last seen timestamps and max z-score over the run history.
• recent_events: changepoints, regime transitions, surprise spikes, cascade alerts in the last hours_back hours.
• run_stats: per-detector run count + findings + average latency.
• headline_summary: one-sentence interpretation (client-renderable).

Gated by admin-only auth in the app-level route layer -- raw endpoint returns public data shape but assume the caller is authenticated in production.