Amazon branded search is the cleanest halo signal there is: nobody searches a brand by name unless something put it in their head, and on TikTok-driven brands that something is usually a video. This returns the daily branded-search volume and click share for the window, the window totals, the peak day, and the Pearson correlation against TikTok views at the requested lag_days — the same regression the analysis endpoint runs.

top_search_terms is always null: Amazon reports branded-search volume per ASIN per day, not the query strings, so there is no term list to return. The field exists so it can be filled later without a breaking change.

Pass asins to scope to specific products; omit for every tracked ASIN. An empty series means branded search isn't tracked for this shop (check branded_search on GET /halo/channels). Single-shop only.