fix(codex): hide gpt-5.5-pro for Codex OAuth users

[rakshith1928]

Issue

Fixes #12038

Context

When authenticated with OpenAI using Codex OAuth (ChatGPT Plus/Pro), Kilo displayed gpt-5.5-pro in the model picker even though the model is not supported by the Codex OAuth backend. Selecting it resulted in a 400 Bad Request response from the server

Implementation

Added a DISALLOWED_MODELS set to the Codex OAuth plugin and excluded gpt-5.5-pro during model filtering for OAuth authentication.

The existing fallback logic for supported GPT models remains unchanged, so only the unsupported model is filtered out while API key authentication continues to expose all available models.

Also added regression tests covering:

• gpt-5.5-pro is hidden for OAuth users.
• Supported Codex/GPT models remain available for OAuth users.
• Non-OAuth (API key) authentication is unaffected.

Screenshots / Video

n/a (small change)

How to Test

Manual/local verification

• Built the extension locally.
• Signed in using OpenAI Codex OAuth.
• Verified gpt-5.5-pro no longer appears in the model picker.
• Verified supported GPT/Codex models are still available.
• Verified API key authentication continues to expose gpt-5.5-pro.

Reviewer test steps

• Sign in using OpenAI → ChatGPT (Codex OAuth).
• Open the model picker.
• Verify gpt-5.5-pro is not listed.
• Switch to an OpenAI API key.
• Verify gpt-5.5-pro is available.

Blocked checks and substitute verification

No additional blockers encountered.

Checklist

• Issue linked above, or exception explained
• Tests/verification described
• Screenshots/video included for visual changes, or marked N/A
• Changeset considered for user-facing changes
• I personally reviewed the diff and can explain the changes, including any AI-assisted work.

Get in Touch

@travix26

[kilo-code-bot]

Code Review Summary

Status: No Issues Found | Recommendation: Merge

Files Reviewed (3 files)

• .changeset/hide-gpt-5-5-pro.md
• packages/opencode/src/plugin/openai/codex.ts
• packages/opencode/test/plugin/codex.test.ts

Incremental update: the only change since the last review is a marker-only commit adding kilocode_change annotations around the existing DISALLOWED_MODELS logic and tests, with no functional change. No new issues found.

Previous Review Summary (commit 93c209b)

Current summary above is authoritative. Previous snapshots are kept for context only.

Previous review (commit 93c209b)

Status: No Issues Found | Recommendation: Merge

Files Reviewed (3 files)

• .changeset/hide-gpt-5-5-pro.md
• packages/opencode/src/plugin/openai/codex.ts
• packages/opencode/test/plugin/codex.test.ts

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_{Review guidance: REVIEW.md from base branch main}

[chrarnoldus]

thanks