diff --git a/CommandHook/ICommandHookListener.cs b/CommandHook/ICommandHookListener.cs
index a4bdeee..8a62944 100644
--- a/CommandHook/ICommandHookListener.cs
+++ b/CommandHook/ICommandHookListener.cs
@@ -2,9 +2,27 @@ using System.Collections.Generic;
 
 namespace CommandHook;
 
+/// <summary>
+/// Implement this to watch chat commands through CommandHook. Pass your
+/// implementation to <see cref="CommandHookModSystem.Register"/>.
+/// </summary>
 public interface ICommandHookListener
 {
+    /// <summary>
+    /// Your mod's id. Used as the namespace key so two mods can register
+    /// for the same command without colliding, and to find your existing
+    /// registration when you call <see cref="CommandHookModSystem.Register"/> again.
+    /// </summary>
     string ModId { get; }
+
+    /// <summary>
+    /// The command names to watch, without the leading slash (e.g. "tp", not "/tp").
+    /// Return null or an empty list to stop watching anything.
+    /// </summary>
     IReadOnlyList<string> Commands { get; }
+
+    /// <summary>
+    /// The Before/After delegates to invoke for the commands in <see cref="Commands"/>.
+    /// </summary>
     CommandRegistration Registration { get; }
 }