Confirm by changing [ ] to [x] below to ensure that it's a bug:

• I've gone through Developer Guide and API reference
• I've checked AWS Forums and StackOverflow for answers
• I've searched for previous similar issues and didn't find any solution

Describe the bug
Using expired tokens results in retries. I've seen long runtimes of sts.getCallerIdentity, for example, retrying with an expired credential.

Is the issue in the browser/Node.js?
Node.js

If on Node.js, are you running this on AWS Lambda?
No.

Details of the browser/Node.js version
v15.3.0

SDK version number
aws-sdk@2.601

To Reproduce (observed behavior)
Use an expired credential, call sts.getCallerIdentity, observe that it retries using the expired credential

Expected behavior
Expired credentials should not be retried (since presumably they can never become un-expired). Or, if this is to account for clock skew or something nuanced like that, perhaps a sensible number of retries should be used (maybe just one?)

Additional context
This was observed in AWS CDK, on which I raised a bug here. There, @rix0rrr asserts that retrying retryable requests is appropriate, but that a request using an expired credential should not be retryable.

The offending code seems to be here.

Can you explain the logic of having expired tokens be explicitly retryable if this is intentional?