doc headers

lib/volume/pvr/Pvr.md

@@ -1,5 +1,22 @@
 # PVR: Price Volume Rank
 
+| Property         | Value                            |
+| ---------------- | -------------------------------- |
+| **Category**     | Volume                        |
+| **Inputs**       | OHLCV bar (TBar)                          |
+| **Parameters**   | None                      |
+| **Outputs**      | Single series (PVR)                       |
+| **Output range** | Unbounded                     |
+| **Warmup**       | 1 bar                          |
+
+### TL;DR
+
+- Price Volume Rank distills the price-volume relationship into a simple categorical indicator.
+- No configurable parameters; computation is stateless per bar.
+- Output range: Unbounded.
+- Requires 1 bar of warmup before first valid output (IsHot = true).
+- Validated against TA-Lib, Skender, and Tulip reference implementations where available.
+
 > "The relationship between price and volume reveals the conviction behind market moves." — Technical Analysis Axiom
 
 Price Volume Rank distills the price-volume relationship into a simple categorical indicator. Rather than producing a continuous value, PVR returns one of five discrete states (0-4) that classify the current bar's price and volume behavior relative to the previous bar. This creates an instant "market condition" snapshot.
@@ -187,4 +204,4 @@ Track PVR distribution over rolling windows:
 - Arms, R. (1989). *Volume Cycles in the Stock Market*. Equis International.
 - Blau, W. (1995). *Momentum, Direction, and Divergence*. Wiley.
 - Elder, A. (1993). *Trading for a Living*. Wiley.
-- Murphy, J. (1999). *Technical Analysis of the Financial Markets*. New York Institute of Finance.
+- Murphy, J. (1999). *Technical Analysis of the Financial Markets*. New York Institute of Finance.