[docs] Document Python starter template migration to TypeScript AppHost (aspire-py-starter)

src/frontend/src/content/docs/get-started/aspire-sdk-templates.mdx

@@ -39,10 +39,12 @@ The following Aspire solution templates are available (assume the solution is na
   - **AspireSample.ApiService**: An [ASP.NET Core Minimal API](https://learn.microsoft.com/aspnet/core/fundamentals/minimal-apis) project that provides data to the frontend.
   - **AspireSample.Web**: A React-based frontend application with TypeScript configured to work with the Aspire app.
 
-- **Aspire Starter App with FastAPI and React**: This template provides a Python-based starter app with the following projects:
-  - **AspireSample.AppHost**: The orchestrator project for managing the app's services.
-  - **AspireSample.ApiService**: A [FastAPI](https://fastapi.tiangolo.com/) Python backend service that provides data to the frontend.
-  - **AspireSample.Web**: A React-based frontend application with TypeScript.
+- **Aspire Starter App with FastAPI and React**: This template provides a Python-based starter app using a **TypeScript AppHost**. It includes:
+  - **apphost.ts**: The TypeScript AppHost that orchestrates the app's services using `addUvicornApp`.
+  - **app/**: A [FastAPI](https://fastapi.tiangolo.com/) Python backend service that provides data to the frontend.
+  - **frontend/**: A React-based frontend application with TypeScript.
+
+  The template supports an optional `--use-redis-cache` flag that adds a Redis cache resource to the app. Because the AppHost is TypeScript-based, the .NET SDK is not required to scaffold or run this template.
 
   For more information on Python workloads in Aspire, see [Python integration](/integrations/frameworks/python/) and [Add Aspire to an existing app](/get-started/add-aspire-existing-app/).
 

src/frontend/src/content/docs/reference/cli/commands/aspire-new.mdx

@@ -124,11 +124,23 @@ Each command represents a template. Pass the `--help` parameter to the template
 | ---------------------- | --------------------------------- |
 | `aspire-starter`       | Starter App (ASP.NET Core/Blazor) |
 | `aspire-ts-cs-starter` | Starter App (ASP.NET Core/React)  |
-| `aspire-py-starter`    | Starter App (FastAPI/React)       |
+| `aspire-py-starter`    | Starter App (FastAPI/React) |
 | `aspire-ts-starter`    | Starter App (Express/React)       |
 | `aspire-empty`         | Empty (C# AppHost)                |
 | `aspire-ts-empty`      | Empty (TypeScript AppHost)        |
 
+### aspire-py-starter options
+
+The `aspire-py-starter` template accepts the following additional options:
+
+- **`--use-redis-cache`**
+
+  Scaffold the template with an optional Redis cache resource in the TypeScript AppHost. Accepts `true` or `false`. Defaults to prompting interactively.
+
+  ```bash title="Aspire CLI"
+  aspire new aspire-py-starter --use-redis-cache true
+  ```
+
 ## Examples
 
 - Create an Aspire solution from the template. Because the template was selected (`aspire-starter`), you're prompted for the name, output folder, and template version.

src/frontend/src/content/docs/whats-new/aspire-13-3.mdx

@@ -10,6 +10,7 @@ tableOfContents:
 ---
 
 import { Steps, Aside } from '@astrojs/starlight/components';
+import LearnMore from '@components/LearnMore.astro';
 import { Image } from 'astro:assets';
 import LearnMore from '@components/LearnMore.astro';
 import azureFrontDoorIcon from '@assets/icons/azure-front-door-icon.png';
@@ -136,3 +137,30 @@ You can also disable it in `launchSettings.json`:
 <LearnMore>
   For more details on container networking, see [Inner-loop networking overview](/fundamentals/networking-overview/).
 </LearnMore>
+
+## 🐍 Python starter template migrated to TypeScript AppHost
+
+The `aspire-py-starter` template (Starter App with FastAPI and React) has moved from the `dotnet new` template system to the Aspire CLI template system and now uses a **TypeScript AppHost** instead of a C# AppHost. This aligns it with the same pattern as the `aspire-ts-starter` template.
+
+**What changed for you:**
+
+- Use `aspire new aspire-py-starter` instead of `dotnet new aspire-py-starter`.
+- The AppHost is now authored in TypeScript — the **.NET SDK is no longer required** to scaffold or run the Python starter.
+- The generated TypeScript AppHost uses `addUvicornApp` to run the FastAPI backend.
+- A new `--use-redis-cache` option is available to scaffold the template with an optional Redis cache resource.
+
+```bash title="Aspire CLI"
+# Basic Python starter
+aspire new aspire-py-starter
+
+# Python starter with Redis cache
+aspire new aspire-py-starter --use-redis-cache true
+```
+
+<Aside type="caution" title="Breaking change">
+`dotnet new aspire-py-starter` is no longer available. Existing projects created with the old template continue to work, but new projects should use `aspire new aspire-py-starter` going forward.
+</Aside>
+
+<LearnMore>
+  For details on the `aspire new` command and all available templates, see [aspire new command](/reference/cli/commands/aspire-new/).
+</LearnMore>