improve diagrams

Author: kentcdodds

exercises/01.ping/README.mdx

@@ -25,6 +25,52 @@ connection by spawning a new process and then use STDIO to communicate with it.
 	keep things simple and not much changes in this workshop by using `stdio`.
 </callout-info>
 
+## MCP Initialization
+
+Here's what happens when the client initializes the session with the server:
+
+```mermaid
+sequenceDiagram
+    participant Host
+    participant Client
+    participant Server
+
+    Host->>+Client: Initialize client
+    Client->>+Server: Initialize session with capabilities
+    Server-->>Client: Respond with supported capabilities
+
+    Note over Host,Server: Active Session with Negotiated Features
+
+    loop Client Requests
+        Host->>Client: User- or model-initiated action
+        Client->>Server: Request (tools/resources)
+        Server-->>Client: Response
+        Client-->>Host: Update UI or respond to model
+    end
+
+    loop Server Requests
+        Server->>Client: Request (sampling)
+        Client->>Host: Forward to AI
+        Host-->>Client: AI response
+        Client-->>Server: Response
+    end
+
+    loop Notifications
+        Server--)Client: Resource updates
+        Client--)Server: Status changes
+    end
+
+    Host->>Client: Terminate
+    Client->>-Server: End session
+    deactivate Server
+```
+
+<callout-success>
+	This is all handled by the MCP SDK automatically. Once you set up your server
+	and connect it to a transport, the SDK will handle the initialization and
+	negotiation of capabilities.
+</callout-success>
+
 ## MCP `ping`
 
 ```mermaid
@@ -35,6 +81,11 @@ sequenceDiagram
 	Server-->>Client: JSON-RPC Response {"result": {}}
 ```
 
+<callout-success>
+	The MCP SDK handles the ping request for you. Just get the server set up with
+	a transport and you're good to go.
+</callout-success>
+
 A "ping" is a common concept in protocol design. It's a simple request to check
 if a connection is working. In this exercise, we'll implement a `ping` tool
 for our MCP server.

exercises/05.sampling/README.mdx

@@ -36,9 +36,9 @@ sequenceDiagram
 	Client->>App: Request permission for sampling
 	App->>User: Request permission for sampling
 	alt User approves
-		App->>Client: Permission granted
-		Client->>LLM: Forward sampling request
-		LLM-->>Client: Generation (completion)
+		App->>LLM: Forward sampling request
+		LLM-->>App: Generation (completion)
+		App-->>Client: Sampling result
 		Client-->>Server: Sampling result
 	else User rejects
 		App->>Client: Permission denied