[Cursor extension] `model_reasoning_summary = "detailed"` resolves to `summary=none` for new turns

What version of Codex are you using?

Codex IDE extension: openai.chatgpt-26.721.30844-win32-x64

What editor and platform are you using?

• Editor: Cursor
• Platform: Windows x64
• Authentication: ChatGPT account
• Model: gpt-5.6-sol

The exact Cursor version is not present in the captured logs.

What issue are you seeing?

The documented configuration setting:

model_reasoning_summary = "detailed"
model_supports_reasoning_summaries = true
hide_agent_reasoning = false
show_raw_agent_reasoning = true

is ignored when a new conversation/turn is created in the Cursor Codex extension. The extension explicitly resolves the effective turn setting to summary=none, and all returned reasoning-summary items contain zero summary parts.

This report concerns reasoning summaries, not access to raw chain-of-thought.

Expected behavior

A new turn should resolve the effective reasoning-summary setting to detailed (or at least a supported non-none value), and completed reasoning-summary items should contain readable summary parts.

Expected diagnostic shape:

Reasoning summary turn-start config resolved ... summary=detailed
Reasoning summary item completed ... summaryPartCount=>0

Actual behavior

A newly created conversation resolves to:

Conversation created conversationId=<redacted>
Reasoning summary turn-start config resolved concurrentReasoningSummariesFeatureOverrideEnabled=false conversationId=<redacted> requestApprovalPolicy=on-request requestApprovalsReviewer=auto_review requestPermissionProfile=null requestRuntimeWorkspaceRootCount=0 requestSandboxPolicyType=workspaceWrite requestSandboxWritableRootCount=2 resolvedApprovalPolicy=on-request resolvedApprovalsReviewer=auto_review summary=none useAppServerPermissionDefault=false

Every reasoning item then completes without summary content:

Reasoning summary item completed itemId=<redacted> summary=[] summaryPartCount=0 threadId=<redacted> turnId=<redacted>

Steps to reproduce

1. On Windows, install/use Codex IDE extension openai.chatgpt-26.721.30844-win32-x64 in Cursor.
2. Configure ~/.codex/config.toml with:

``toml
model = "gpt-5.6-sol"
model_reasoning_summary = "detailed"
model_supports_reasoning_summaries = true
hide_agent_reasoning = false
show_raw_agent_reasoning = true
``

1. Fully close Cursor and terminate remaining Codex/app-server processes.
2. Reopen Cursor.
3. Create a completely new conversation.
4. Send a prompt that causes multiple reasoning/tool steps.
5. Inspect the Codex extension logs.

Reproducibility and diagnostics already tried

• Reproduces in a completely new conversation after a full restart.
• Adding model_supports_reasoning_summaries = true does not change the result.
• The model still emits multiple rs_... reasoning items, but each has summary=[] and summaryPartCount=0.
• Starting Cursor with:

``powershell
Cursor.exe --enable-proposed-api openai.chatgpt
``

removes the separate chatSessionsProvider activation error, but does not change summary=none.

• The logs repeatedly show:

``text
Concurrent reasoning summaries feature override resolved featureOverride=null
Concurrent reasoning summaries thread-start config resolved featureOverride=null threadStartConfig=null
Reasoning summary turn-start config resolved concurrentReasoningSummariesFeatureOverrideEnabled=false ... summary=none
``

This suggests that the IDE extension's turn-start configuration or feature-gating path is overriding or failing to propagate model_reasoning_summary from the effective Codex configuration.

Additional notes

Other warnings in the logs (unsupported MCP resources/list, PowerShell shell snapshot, plugin prompt length, /settings/user 403) appear unrelated because summary=none is selected directly at turn start before the empty reasoning items are received.

Raw internal reasoning is not expected to be exposed for hosted models; the issue is specifically that the documented reasoning-summary setting does not take effect.