get_premarket_scan_history

ai.signal8/mcp · Verify this server

Historical MARKET-WIDE premarket scan for a single PAST trade date. For the requested ET date, returns every ticker with that day's premarket (default) session volume and its relative volume (RVOL) vs the trailing 90-day same-session baseline — the SAME RVOL math as get_rvol_history, but across the whole market for one date instead of one ticker across many dates. Filter by RVOL, market cap, price, and float to backtest screens like "sub-$500M tickers with premarket RVOL > 5 on 2026-07-20" in one call. Rows are ranked by RVOL descending. A future or non-trading date returns an empty list with an explanatory reason (not an error). Every row also reports "baselineState" (why its RVOL is or is not null), "advRatio" (volume ÷ trailing 30-session average FULL-DAY volume) and "advDays"; set includeNoHistory=true to surface high-volume tickers that have no computable RVOL at all, such as first-session new listings. Each row ALSO publishes the RVOL denominator itself as "baselineVolume" (shares) plus a "baselineThin" flag (true when that denominator is under 200 shares): a 90x RVOL off a 1-share baseline is arithmetically correct and analytically worthless. That is almost entirely an asOfTime-basis effect (0.1% of full-session rows vs ~38% at the 04:30 cutoff, falling to ~9% by 09:15) and it skews to LIQUID LARGE CAPS that simply do not trade early, NOT to microcaps. Screen it out with minBaselineVolume and/or minSessionVolume. The response "meta" also reports asOfApplied / asOfIgnored / asOfIgnoredReason, so a time-of-day request that could not be honoured is visible instead of quietly returning full-session numbers. Charged per your API tier.