Error: 403 Authentication failed for Muse Spark 1.3 Contributor

[iAziz786]

Summary

I'm constantly seeing this intermittent issue of getting this error.

Expected Behavior

The model should work file with no errors.

Actual Behavior

Getting this error:

Error: 403 Authentication failed. Please check your credentials.
   Authentication failed. Please check your credentials. (type=permission_error)

Although I have active plan. It's happening again and again for some time then it started working.

Steps to reproduce the issue

1. Using the model normally it's happening often. No extra step needed.

Command Code Version

1.66.0

Operating System

macOS

Terminal/IDE

ghostty

Shell

zsh

Session file (optional)

No response

Fix prompt (optional)

No response

Additional context

OS: macOS Tahoe 26.7

[iAziz786]

Another user reported this from Discord:

[lee5312]

Controlled reproduction on 2026-09-29 (Provider API, meta/muse-spark-1.3-contributor):

• The same unmodified Command Code API key returns 200 for gpt-5.6-sol from a Windows laptop, and 200 for Muse from an Azure host.
• From the laptop, the documented /provider/v1/chat/completions endpoint intermittently returns 403 permission_error / Authentication failed. Please check your credentials. for Muse. One captured failure: x-trace-id: bcf923313633b31501ecc91270739d17, cf-ray: a42a5dce5f7e6131-HKG.
• Cloudflare's client-side trace reports loc=KR for the laptop. Calls routed through NRT/KIX succeeded, while HKG calls failed; a DNS/IP pin did not reliably select a good edge.
• The official Command Code CLI 1.66.0, using that same key on the same laptop with --no-session --model meta/muse-spark-1.3-contributor --print, returned OK immediately after the captured Provider API 403.
• The API failures can persist across multiple bounded retries, so a one-off retry is insufficient. The response contains no actionable error code distinguishing an edge/routing failure from a region or account restriction.

Could you inspect this trace and confirm the actual rejection reason, then fix the HKG Provider API route or its error mapping? No key or prompt data is included here.