[VS Code] Add inline comments and annotations to Plan mode plans

What variant of Codex are you using?

VS Code Extension

What feature would you like to see?

Please add inline comments and annotations to generated Plan mode plans in the Codex VS Code extension.

After Codex generates a plan, the user should be able to select a specific heading, paragraph, or list item and attach a comment to that exact fragment.

The extension should allow multiple annotations to be collected and submitted together in a single chat message, with each comment retaining the selected plan text as context.

Current behavior

The user can either accept the entire plan or provide a general free-form response asking Codex to change it.

For a large plan, this forces the user to manually quote or restate every relevant section and explain which comment belongs to which part of the plan. This is slow, ambiguous, and makes Plan mode impractical for reviewing non-trivial implementation plans.

Requested behavior

• Allow selecting text inside a generated Plan mode plan.
• Provide an Add comment action for the selected fragment.
• Allow multiple comments on different plan fragments.
• Show the selected fragments and their comments in the chat composer.
• Submit all annotations to Codex in one turn.
• When revising the plan, preserve unaffected sections instead of regenerating unrelated details.

This should work similarly to inline comments during code or document review.

Why this matters

The primary value of Plan mode is reviewing and correcting an implementation approach before any code is changed.

Without comments tied to specific plan fragments, reviewing a large plan becomes harder than reviewing the resulting code. Inline annotations would make the planning workflow precise, collaborative, and usable for real implementation work.

Related issues

• #35918 requests the same inline annotation workflow for Codex Desktop.
• #35272 requests an "Implement with changes" workflow for the VS Code extension.
• #14463 was an earlier request for direct Plan mode review and editing.