I had an old version of cwltool installed (i.e., the reference implementation, from https://github.com/common-workflow-language/cwltool), and when I tried to run it today I got:

Tool definition failed initialization: ('https://w3id.org/cwl/CommonWorkflowLanguage.yml', HTTPError(u'404 Client Error: Not Found for url: https://w3id.org/cwl/CommonWorkflowLanguage.yml',))

I thought the problem likely had to do with an update, so I went back to that site, downloaded and installed the latest version (I generally install from source). But I still get the same error.

Anyone know what the problem is? Thanks.