"Malicious scraper" error when script download videos

Hello, I'm trying to write a console app that will use the API to get the file url's for some of my favorite shows, and then archive them (download) for offline viewing.

I tried using the /videos endpoint like:
> https://www.giantbomb.com/api/videos/?filter=video_show:[THE_SHOW_I_LIKE]&api_key=[MY_API_KEY]&format=json

However, when I make a GET request from a Csharp console app, I get an error page that tells me I'm a malicious scraper, because I don't have a valid user agent (like from a browser).

If I include a user agent manually (using my httpClient's ProductInfoHeader()), I am able to get the response of all the videos I'd like to download.

Is this legal use?

I don't see how others are able to download videos without being able to utilize the /videos endpoint like this - and I consider it valid as a way to index and then download videos that are available.

Thanks