How do I launch Appstream Desktop Application 2.0 after JumpCloud completes login to Appstream Web?

While the core explanation „the answer of the re:Post Agent“ of the URI scheme is correct, two critical administrative steps are missing for a seamless production rollout:

• SAML Relay State Configuration: To ensure JumpCloud redirects users directly to the desktop client rather than the browser, your SAML Relay State must be configured to point to the client endpoint. By default, many IdP setups point to the standard Web Portal URL, which can cause users to get "stuck" in the browser session.
• Browser Protocol Handling (GPO): To avoid the repetitive "Always allow this site to open the link" prompt, administrators should deploy a Group Policy (GPO) for Chrome/Edge using the AutoLaunchProtocolsFromOrigins policy. Adding amazonappstream to the allowed protocols for your AWS domain ensures the AppStream client launches instantly after the JumpCloud login. These steps are essential for a professional "native" user experience.

After JumpCloud completes login to AppStream 2.0 via the web, you have a couple of options for launching desktop applications:

If you want to redirect the streaming session from the web browser to the AppStream 2.0 client (also known as the WorkSpaces Applications client), you can configure this by generating a streaming URL with the "amazonappstream:" prefix. When users access this URL after authentication, their browser will detect the need for the client and prompt them to use it. If the client is installed, users can choose to continue their streaming session using the client instead of the browser. If the client isn't installed, users will be prompted to download and install it, after which they can refresh their browser to start the streaming session using the client.

The AppStream 2.0 client offers two connection modes:

• Classic mode: Applications stream in the AppStream 2.0 session window, similar to browser-based streaming, and is the recommended default mode.
• Native application mode: Applications function similarly to locally installed applications, with icons appearing in the taskbar and supporting application keyboard shortcuts for seamless switching between local and remote applications.

Administrators can control which connection mode users have access to and can deploy the client using PowerShell scripts or the Enterprise Deployment Tool for large-scale installations.
Sources
AppStream 2.0 client for Windows - Best Practices for Deploying Amazon AppStream 2.0
Redirect a Streaming Session from the Web Browser to the WorkSpaces Applications Client - Amazon WorkSpaces Applications