Return how ONE page's Google Search performance changed over time. Pass start_date and end_date together as inclusive JST dates; comparison dates are not supported. Or pass preset (last_4_weeks, last_12_weeks or year_to_date) for the same periods as the app's period picker: the period ends on the last Saturday that closes a complete week (weeks run Sunday to Saturday, judged in the site time zone), and year_to_date starts on January 1 of the year of that Saturday; preset cannot be combined with start_date or end_date, and period.preset echoes it. Omitting all of them preserves the current now-minus-30-days rolling window, which may touch 31 JST dates because GSC filters by date inclusively. Explicit dates are converted to JST day boundaries for GSC rows. granularity defaults to day for windows up to about 35 days and week for longer windows; pass it to override. Weeks run Sunday to Saturday and each weekly date is that week's Sunday; weeks at the edge of the period hold only the days inside it. Buckets without GSC rows are omitted. Google-search only; data lags 1-2 days. site_id is optional when OAuth-authenticated (omitting it uses the primary site). When the user names a specific site, such as the sample site, call list_sites first and pass that site_id. For cross-page snapshots use get_breakdown(dimension='page'); for query trends use get_keyword_performance.