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lib/channels/atrbands/atrbands.md

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 # ATRBANDS: Average True Range Bands
 
+| Property         | Value                            |
+| ---------------- | -------------------------------- |
+| **Category**     | Channel                        |
+| **Inputs**       | OHLCV bar (TBar)                          |
+| **Parameters**   | `period`, `multiplier` (default 2.0)                      |
+| **Outputs**      | Multiple series (Upper, Lower)                       |
+| **Output range** | Tracks input                     |
+| **Warmup**       | `period` bars                          |
+
+### TL;DR
+
+- ATR Bands create a volatility-adaptive envelope by projecting Wilder's Average True Range above and below a central Simple Moving Average.
+- Parameterized by `period`, `multiplier` (default 2.0).
+- Output range: Tracks input.
+- Requires `period` bars of warmup before first valid output (IsHot = true).
+- Validated against TA-Lib, Skender, and Tulip reference implementations where available.
+
 ATR Bands create a volatility-adaptive envelope by projecting Wilder's Average True Range above and below a central Simple Moving Average. Unlike fixed-percentage envelopes or standard-deviation bands, ATR Bands use True Range to measure volatility, making them robust for assets with gaps, pre-market moves, and 24/7 trading where the "hidden" volatility between bars is significant. The True Range captures the maximum of intra-bar range, gap-up distance, and gap-down distance, ensuring that overnight gaps contribute fully to band width even when the current bar's open-to-close range is narrow.
 
 ## Historical Context