📚 Improve usage documentation of API type generator script

mcp/types-generator/README.md

@@ -1,7 +1,8 @@
 # Types Generator
 
 This subproject contains helper scripts used in the development of the
-Penpot MCP server for generate the types yaml.
+Penpot MCP server, specifically for the generation of a YAML file containing 
+Penpot plugin API types and their documentation.
 
 ## Setup
 
@@ -12,15 +13,36 @@ Install the environment via (optional, already handled by `build` script)
 
     pixi install
 
+## Running the API Documentation Preparation Script
 
-### Buld API types
-
-The script `prepare_api_docs.py` reads API documentation from the Web
-and collects it in a single yaml file, which is then used by an MCP
+The script `prepare_api_docs.py` reads API documentation from a Web URL
+and collects it in a single YAML file, which is then used by an MCP
 tool to provide API documentation to an LLM on demand.
 
+Successful execution will generate the output file `../packages/server/data/api_types.yml`.
+
+### Generating the YAML File for a Given URL
+
 Running the script:
 
-    ./build <optional-url>
+    pixi run python prepare_api_docs.py <url>
 
-This will generate `../packages/server/data/api_types.yml`.
+You can alternatively run `./build <url>`, which additionally performs pixi environment installation. 
+
+For example, to generate the API documentation based on the current PROD Penpot API documentation,
+use the URL
+
+    https://doc.plugins.penpot.app
+
+### Generating the YAML File Based on the Current Documentation in the Repository  
+
+Requirement: [Caddy](https://caddyserver.com/download) must be installed and available in the system path.
+
+To generate the API documentation based on the current documentation in the repository,
+run the `build:types` script in the parent directory, i.e.
+
+    cd ..
+    pnpm run build:types
+
+This will spawn a local HTTP server on port 9090 and run the `prepare_api_docs.py` script with the 
+URL `http://localhost:9090`.