diff --git a/CommandHook/CommandData.cs b/CommandHook/CommandData.cs
index b7b905c..4c44adc 100644
--- a/CommandHook/CommandData.cs
+++ b/CommandHook/CommandData.cs
@@ -2,23 +2,54 @@ using Vintagestory.API.Server;
 
 namespace CommandHook;
 
+/// <summary>
+/// The data passed to Before/After listeners for a single command invocation.
+/// Passed by ref through the hot path, no allocation per command.
+/// </summary>
 public struct CommandData
 {
+    /// <summary>
+    /// The player who ran the command, or null if it came from the server console.
+    /// </summary>
     public readonly IServerPlayer? Sender;
+
+    /// <summary>
+    /// The full command text as typed, including the leading slash.
+    /// </summary>
     public readonly string FullCommand;
+
+    /// <summary>
+    /// The command name only, without the leading slash (matches what listeners
+    /// register in <see cref="ICommandHookListener.Commands"/>).
+    /// </summary>
     public readonly string CommandName;
     private byte flags;
 
     private const byte FlagIsPlayerCommand = 1 << 0;
     private const byte FlagCancel = 1 << 1;
 
+    /// <summary>
+    /// True if a player ran this command, false if it came from the server console.
+    /// Equivalent to <c>Sender != null</c>.
+    /// </summary>
     public bool IsPlayerCommand => (flags & FlagIsPlayerCommand) != 0;
+
+    /// <summary>
+    /// Set this to true in a Before listener to stop the command from executing.
+    /// Stops any remaining Before listeners from running too, and skips After entirely.
+    /// </summary>
     public bool Cancel
     {
         get => (flags & FlagCancel) != 0;
         set => flags = value ? (byte)(flags | FlagCancel) : (byte)(flags & ~FlagCancel);
     }
 
+    /// <summary>
+    /// Creates the command data for a single invocation.
+    /// </summary>
+    /// <param name="sender">The player who ran the command, or null for console.</param>
+    /// <param name="commandName">The command name without the leading slash.</param>
+    /// <param name="fullCommand">The full command text as typed, including the leading slash.</param>
     public CommandData(IServerPlayer? sender, string commandName, string fullCommand)
     {
         Sender = sender;