False "rate_limited" error on gpt-5.1-codex in CLI v0.0.358

[Daplugg23]

Describe the bug

When attempting to use the newly released gpt-5.1-codex model via the Copilot CLI, the request fails immediately with a rate_limited error.

This appears to be a false error for the following reasons:

1. My Copilot Pro account has premium requests remaining.
2. The rate_limited error happens only for the gpt-5.1-codex model.
3. All other models work correctly from the CLI.
4. The gpt-5.1-codex model has already been successfully enabled in my account's Copilot settings (via the web UI).

Affected version

0.0.358 Commit: f5a8b1e76

Steps to reproduce the behavior

1. Ensure you have a Copilot Pro account with premium requests available.

2. Go to GitHub settings and enable the gpt-5.1-codex model.

3. From the terminal, run any Copilot CLI command, specifying the model:
   copilot --model gpt-5.1-codex "read the directory"

4. Observe the immediate error.

Expected behavior

The Copilot CLI should connect to the gpt-5.1-codex model and execute the prompt, consuming premium requests as expected.

Actual Behavior
The CLI immediately fails and prints the rate_limited error message:
✗ Model call failed: {"message":"Rate limit exceeded. Please review our [Terms of Service](https://docs.github.com/en/site-policy/github-terms/github-terms-of-service).","code":"rate_limited"}

Additional context

Environment & Context

• OS: Windows 11 Pro (64-bit operating system, x64-based processor)
• Terminal: Windows Terminal
• Shell: Powershell 7.5.4
• Hardware: AMD Ryzen 9 9950X3D, 64.0 GB RAM
• Subscription: Copilot Pro
• Troubleshooting Steps Taken:

1. Verified all other models work.
2. Verified gpt-5.1-codex is enabled in settings.
3. Logged out and logged back in.
4. Performed a clean uninstall and reinstall of the 0.0.358 CLI.

• Related Issues: This seems related to or a continuation of Issue 0.0.357 Unable to use gpt-5.1-codex model #558, which reported access problems for this model on v0.0.357. This new rate_limited error might be the new symptom in v0.0.358.

[JuanCS-Dev]

🔍 Additional Investigation - Linux Environment

I can confirm this issue on Linux Mint / Ubuntu 24.04 as well:

Environment

• OS: Linux Mint Vertice (Kernel 6.14.0-35-generic)
• Node.js: v22.20.0
• npm: 10.9.3
• Copilot CLI: 0.0.358 (Commit: f5a8b1e76)
• Subscription: Copilot Pro

Test Results

✅ gpt-5 works:

$ copilot --model gpt-5 -p "say hello" --allow-all-tools
Hello!

Total usage est:       1 Premium request

❌ gpt-5.1-codex fails immediately:

$ copilot --model gpt-5.1-codex -p "test" --allow-all-tools
Model call failed: {"message":"Rate limit exceeded. Please review our [Terms of Service](https://docs.github.com/en/site-policy/github-terms/github-terms-of-service).","code":"rate_limited"} (Request ID: 8F3E:31FAD5:2A47F1:3B12F6:691A46EE)

Key Observations

1. Cross-platform issue: Now confirmed on Windows 11 (original report) and Linux
2. Instant failure: Error happens before any actual API call (no delay)
3. Other models working: gpt-5, gpt-5.1, and gpt-5.1-codex-mini all work fine
4. Premium requests available: Account has remaining quota

Hypothesis

This appears to be a model validation or permission check issue in the CLI, not an actual rate limit from the API:

• The error is immediate (no network delay)
• Request ID is generated, suggesting it reaches GitHub's API
• Possibly related to the fix in 0.0.357 Unable to use gpt-5.1-codex model #558 - the model was re-enabled but with incorrect permission flags?

Would the maintainers be able to check if gpt-5.1-codex has different rate limit rules or requires additional account permissions compared to other gpt-5.1 variants?

[GGJdevelope]

Copilot 0.0.360 still has this bug

[alfonsodg]

Yes, the 0.0.360 still has the bug (Cachy OS - Linux)

[Zinnusl]

Fixed for me in 0.0.362 (Windows 10)

[N-sources]

Ouï y turned up hge &:@