Microsoft's NuGet server API documentation for enumerating package versions says the API response should be 404 when the package source has no versions of the requested package:
https://learn.microsoft.com/en-us/nuget/api/package-base-address-resource#enumerate-package-versions

But ProGet currently returns 200 with an empty array:

{
    "versions": []
}

The documentation doesn't say the 404 should have specific body content, but just for comparison, api.nuget.org returns an XML body:

<?xml version="1.0" encoding="utf-8"?>
<Error>
    <Code>BlobNotFound</Code>
    <Message>The specified blob does not exist.
RequestId:d5844934-501e-000f-5804-f3cb9b000000
Time:2023-09-29T18:43:32.7072199Z</Message>
</Error>

The reason this is an issue for me is because I use the Version Lens extension for VS Code, which currently relies on the documented 404 behavior:
https://marketplace.visualstudio.com/items?itemName=pflannery.vscode-versionlens

That one works, thanks!

That URL isn't working for me either. It says "There is no feed with that name in ProGet."

Here's what the UI tells me to use for my PyPI feed called "Python", which gives me "Endpoint not found":

curl https://{proget}/pypi/Python/upload --user <user>:<password> --upload-file <file-path>

When I click the "Add Package" button for my PyPI feed, the "Publish with cURL (command line)" button displays information for twine instead of curl.

I found that I can change the button's target URL from "push" to "curl", and curl instructions appear. However, it says to use a URL that gives a 404, e.g. https://myproget/pypi/myfeed/upload.

I can see that the manual upload button POSTs to /pypi-packages/add-package/upload?feedId=123. Are we supposed to use that endpoint instead? I haven't been able to get it to work with curl.