if your VS Code with the InterSystems Language Server isn’t fetching the namespace list, and you’ve confirmed the namespace exists and api/atelier is enabled, the next things to check are usually around connection config + network/auth:

make sure settings.json has the correct server, port, scheme (http vs https), and credentials. even small typos or wrong case in username/password can block fetching.

try using “Choose Server and Namespace” in ObjectScript Explorer — sometimes the cached connection info trips the extension up.

check for any firewall or proxy on Ubuntu ARM64 that could be blocking the VS Code extension from reaching the web app.

confirm the extension version (2.8.0) is fully compatible with IRIS 2024.3; occasionally newer IRIS builds need the latest language server release.

basically, the extension looks fine, so it’s almost always a config or network hiccup, not a namespace/server issue.