[Docs][Desktop] Document side-conversation identity, lifecycle, inheritance, and limitations

Summary

Codex Desktop exposes side conversations, but the official documentation does not provide a dedicated contract for their identity, lifecycle, inherited context, persistence, or capabilities.

The current Projects and chats page explains separate chats and shared Project context. It does not explain what a side conversation is or how it differs from a normal Codex chat.

Documentation gap

Please document:

• whether a side conversation is persistent, searchable, resumable, archivable, or intentionally ephemeral;
• how users can identify it, copy its conversation ID or deep link, and determine its parent conversation;
• which parent transcript content, Project instructions, files, attachments, permissions, tools, Skills, plugins, memories, and working-directory context it inherits;
• whether activity in the side conversation can alter or interrupt the parent conversation;
• whether Goals, subagents, background work, file edits, external actions, and cross-thread messaging are supported;
• how behavior differs across Codex Desktop, CLI/TUI, IDE extension, and selected-text sidebars; and
• how users can preserve or promote a valuable side conversation into a normal persistent chat.

Why this matters

A side conversation can look and behave like an ordinary capable Codex chat. Without an official lifecycle and capability contract, users must rely on UI inference, assistant-provided runtime descriptions, source-code inspection, or experiments before deciding whether the conversation is suitable for consequential work.

The ambiguity also makes it difficult to know whether work will survive restart, appear in normal history, remain isolated from the parent, or retain access to Project context.

Requested documentation

Publish one canonical side-conversation page with:

1. A lifecycle diagram showing the parent relationship and persistence behavior.
2. A capability matrix covering Desktop, CLI/TUI, IDE extension, and sidebar variants.
3. Explicit inheritance rules for context, files, instructions, tools, permissions, and working directory.
4. Clear persistence, search, resume, archive, export, and deletion behavior.
5. A visible Copy ID / Copy deep link action or documented method.
6. A warning in the UI when a side conversation is ephemeral.
7. Links from Projects and chats, the /side command documentation, and the side-conversation UI.

Steps to observe the gap

1. Open a side conversation in Codex Desktop.
2. Attempt to determine its ID, parent relationship, persistence, inherited context, and supported actions from the UI.
3. Review the official Projects and chats documentation.
4. Search the official documentation for “side conversation” and “side chat.”
5. Observe that no dedicated public page defines the side-conversation contract.

Related issues, but not exact duplicates

• #36650 requests a Promote to chat button.
• #31543 requests /side support in the IDE extension.
• #35669 reports compaction and observability failures in ephemeral side conversations.
• #34935 reports persistence loss for selected-text sidebar conversations.
• #38042 requests a broader comparison of Project and runtime types.

Those issues address adjacent features or defects. This request is specifically for one authoritative side-conversation identity, lifecycle, inheritance, and capability document.

Environment

• ChatGPT/Codex Desktop for macOS
• Version 26.818.41509, build 6962
• Observed August 23, 2026

Official documentation reviewed

• https://learn.chatgpt.com/docs/projects