docs: Cover MCP setup in the 4.0 migration guide

docs/04-get-started/02-quickstart.md

@@ -33,7 +33,7 @@ Next, open your newly created project with your favorite AI powered editor. Open
 
 :::important
 
-If you are using Cursor, you will need to **enable the MCP server** in your project settings (_Cursor Settings_ > _Tools & MCPs_).
+If you are using Cursor, you will need to **enable the Serverpod and Dart MCP servers** in your project settings (_Cursor Settings_ > _Tools & MCPs_).
 
 :::
 

docs/11-upgrading/01-upgrade-to-three-five.md

@@ -141,15 +141,50 @@ The first run compiles the native build hooks (this can take about 30 seconds) a
 
 Beyond the server, `serverpod start` also launches the project's Flutter app. By default it uses Flutter's `web-server` device and opens your browser. Pass `--flutter-device <name>` to target a specific device. For IDE debugging, projects scaffolded with 3.5 include a `launch.json` that runs `serverpod start` with the debugger attached; you can copy that file into your existing project from a fresh 3.5 scaffold if you want the same setup.
 
-## Add the agent skills (optional)
+## Set up the agent workflow (optional)
 
-Version 3.5 ships AI agent skills (for editors like Claude Code and Cursor) and an MCP server. Install them with:
+Version 3.5 ships AI agent skills and MCP servers (for editors like Claude Code and Cursor) that let your agent build, run, and inspect your server. A new project configures these during `serverpod create`, so the smoothest way to add the same setup to your upgraded project is to run the same command against the current directory. From the project's root folder, run:
+
+```bash
+$ serverpod create .
+```
+
+Serverpod detects the existing project and adds the missing pieces without touching your source code. It registers the **Serverpod** and **Dart** MCP servers and installs the agent skills for the editor you select. The registration is written to `.mcp.json`, along with editor-specific files (`.cursor/mcp.json` and `.vscode/mcp.json`) in each editor's own format. The `.mcp.json` file looks like this:
+
+```json
+{
+  "mcpServers": {
+    "serverpod": {
+      "command": "serverpod",
+      "args": ["mcp-server", "--server-dir", "<project>_server"]
+    },
+    "dart": {
+      "command": "dart",
+      "args": ["mcp-server"]
+    }
+  }
+}
+```
+
+VS Code's `.vscode/mcp.json` registers the same two servers but nests them under a `servers` key instead of `mcpServers`.
+
+:::warning
+
+Configuration files you created manually can be overwritten, so commit your work before running the command.
+
+:::
+
+If you are using Cursor, enable the **Serverpod** and **Dart** MCP servers in your project settings (_Cursor Settings_ > _Tools & MCPs_).
+
+### Install the skills without the MCP setup
+
+If you already have the MCP servers configured and only want to install or refresh the agent skills, install the skills tool:
 
 ```bash
 $ dart install skills
 ```
 
-From your project's root folder, install the skills for your editor:
+Then, from your project's root folder, pull the skills for your editor:
 
 ```bash
 $ skills get --ide cursor
@@ -167,7 +202,7 @@ Copy the updated Dockerfile from the [3.5 framework template](https://github.com
 
 - **`serverpod start` TUI**: hot reload on save, **R** to hot restart, **M** to create a migration, **A** to apply migrations, **P** to apply a repair migration.
 - **Flutter app spawning** from `serverpod start` so the Flutter app runs alongside the server in the same TUI.
-- **AI agent skills and MCP server** scaffolded during `serverpod create`; existing projects opt in with `dart install skills` and `skills get`.
+- **AI agent skills and MCP servers** scaffolded during `serverpod create`; existing projects opt in by running `serverpod create .`.
 - **Embedded Postgres**: zero-Docker development via `dataPath`.
 - **SQLite database support** as an alternative dialect to Postgres.
 - **Client-side database generation** for the Flutter app.
@@ -185,9 +220,9 @@ Copy the updated Dockerfile from the [3.5 framework template](https://github.com
 
 Running more than one Serverpod server on the same machine can conflict on the default ports (8080 for the main server, 8090 for the database). This is a long-standing limitation, not specific to `serverpod start`. Stop the other server, or run on different ports.
 
-### Agent skills aren't picked up after install
+### Agent skills or MCP servers aren't picked up after setup
 
-Run `skills get` again from the project's root folder. Some editors, like Cursor, require enabling the MCP server in their settings.
+Run `serverpod create .` again from the project's root folder. Some editors, like Cursor, require enabling the **Serverpod** and **Dart** MCP servers in their settings (_Cursor Settings_ > _Tools & MCPs_).
 
 ## Still stuck?