add php doc

README.md

@@ -13,7 +13,7 @@ composer require open-solid/bus
 ### Dispatching Message with the Bus
 
 Think of the "bus" as a mail delivery system for your messages. It follows a specific path, decided 
-by some rules (middleware), to send your messages.
+by some rules (middleware), to send your message and handle it.
 
 Here's a snippet on how to set it up and dispatch a message:
 

src/Envelope/Message.php

@@ -13,6 +13,9 @@
 
 namespace OpenSolid\Bus\Envelope;
 
+/**
+ * A data structure that represents a message to be dispatched by a bus to its handlers.
+ */
 abstract readonly class Message
 {
 }

src/Envelope/Stamp/HandledStamp.php

@@ -13,6 +13,9 @@
 
 namespace OpenSolid\Bus\Envelope\Stamp;
 
+/**
+ * A stamp that marks the message as handled.
+ */
 final readonly class HandledStamp extends Stamp
 {
     public function __construct(

src/Envelope/Stamp/Stamp.php

@@ -13,6 +13,10 @@
 
 namespace OpenSolid\Bus\Envelope\Stamp;
 
+/**
+ * A stamp is a marker that can be used to store metadata and take decisions
+ * during the message journey.
+ */
 abstract readonly class Stamp
 {
 }

src/Envelope/Stamp/Stamps.php

@@ -13,6 +13,9 @@
 
 namespace OpenSolid\Bus\Envelope\Stamp;
 
+/**
+ * A collection of stamps.
+ */
 final class Stamps implements \Countable
 {
     /**