This website allows you to download Youtube video annotations. To download videos itself, go here.
To interface this, request https://cable.ayra.ch/ytdl/annotations.php?id=<id/url>
It's recommended to just submit the plain video id and not the full URL.
Submitting the full URL will (if we are able to extract the Id) redirect to the proper request with the Id.
This means if you plan on submitting URLs instead of Ids, you have to make sure your tool follows HTTP redirects.
On success, the script returns the raw XML file with the annotation content. On failure, an HTTP error is presented. This is most likely to happen if the Id doesn't exists.
We don't load the main video watch page at all, which should make this a pretty solid solution until the backend is completely shut down. This also means that it will likely continue to work for a while after YT no longer delivers annotations on their own.
We deliver the raw XML with annotation marks in it. We currently lack a documentation for the fields in the file but they are not obfuscated in any way.
We don't evaluate the XML file content. All videos have an annotation file with at least one entry.