Prepare firm-brief.md, page-inventory.csv, query-page-current.csv and query-page-previous.csv. Obtain genuine query/page pairs; separate unfiltered Queries and Pages exports cannot be silently joined. Preserve query, page, clicks, impressions, CTR, average position and available country/device fields. Record range, export timestamp, search type, filters, missing rows and coverage. Inspect actual exporter headers before analysis; this kit does not invent a vendor CSV schema.