Add additional documentation

src/BaseControllerV2.ts

@@ -129,6 +129,11 @@ export class BaseController<
     string | never
   >;
 
+  /**
+   * The name of the controller.
+   *
+   * This is used by the ComposableController to construct a composed application state.
+   */
   public readonly name: N;
 
   public readonly metadata: StateMetadata<S>;

src/ComposableController.ts

@@ -6,6 +6,12 @@ import {
 
 /**
  * List of child controller instances
+ *
+ * This type encompasses controllers based up either BaseController or
+ * BaseControllerV2. The BaseControllerV2 type can't be included directly
+ * because the generic parameters it expects require knowing the exact state
+ * shape, so instead we look for an object with the BaseControllerV2 properties
+ * that we use in the ComposableController (name and state).
  */
 export type ControllerList = (
   | BaseController<any, any>

src/ControllerMessenger.ts

@@ -24,6 +24,13 @@ type ExtractEventPayload<Event, T> = Event extends { type: T; payload: infer P }
   : never;
 
 type ActionConstraint = { type: string; handler: (...args: any) => unknown };
+
+/**
+ * A valid ControllerMessenger Event.
+ *
+ * This type is used to constrain generic Event parameters, to ensure valid
+ * Event types are given.
+ */
 export type EventConstraint = { type: string; payload: unknown[] };
 
 /**