The typings for the sourceContext config appear to be incorrect.

sourceContext: {
 url: 'mygiturl',
 revisionId: 'abc',
}

➡️ Error: Invalid JSON payload received. Unknown name "url" at 'debuggee.source_contexts[0]': Cannot find field. in stackdriver logs

sourceContext: { 
git: {
 url: 'mygiturl',
 revisionId: 'abc',
}
}

➡️ works as expected

I'm presuming these nested objects are going to be required for the other source context options too?

Source: