[BUG] Deadlock when using custom commands with awsCredentialExport/awsAuthRefresh

[delicb]

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

When custom commands exist in commands/ directory AND awsCredentialExport/awsAuthRefresh are configured, Claude Code hangs in loading state on first prompt. The credential scripts never execute (confirmed via logging).

What Should Happen?

Expected: Credential scripts should execute and request should succeed.

Actual: Credential scripts never run, Claude Code hangs before attempting credential fetch.

Error Messages/Logs

Steps to Reproduce

1. Configure awsCredentialExport and awsAuthRefresh in settings.json
2. Add any custom command file (e.g., commands/test.md)
3. Start Claude Code
4. Send a prompt
5. Claude Code hangs in loading state indefinitely

Claude Model

Sonnet (default)

Is this a regression?

Yes, this worked in a previous version

Last Working Version

1.x branch, not sure exact which exact version

Claude Code Version

2.0.14

Platform

AWS Bedrock

Operating System

macOS

Terminal/Shell

Other

Additional Information

Workaround: Remove awsCredentialExport/awsAuthRefresh and use AWS credential process via ~/.aws/config instead.

Additional Context:

• Custom commands appear in autocomplete (so they load successfully)
• Without custom commands, awsCredentialExport/awsAuthRefresh work fine
• Manual credentials (AWS_ACCESS_KEY_ID env vars) work with custom commands
• Part of the config:

"awsCredentialExport": "echo '{ \"Credentials\": ' && granted credential-process --profile \"${PROFILE}\" 2> /dev/null && echo '}'",
"awsAuthRefresh": "FORCE_NO_ALIAS=true assume -t ${PROFILE}"