Improve Codex VS Code UX with inline diffs, granular approval, context shortcuts, and custom instructions

What variant of Codex are you using?

Codex VS Code extension

What feature would you like to see?

I would like the Codex VS Code extension to provide a more native and developer-friendly editing workflow, closer to the experience offered by GitHub Copilot.

The main improvements I would like to see are:

1. Inline code changes directly inside the editor

Instead of reviewing changes mainly through a separate diff file/view, Codex should show proposed edits directly inside the currently opened file.

For example:

• Removed code highlighted in red
• Added code highlighted in green
• Accept / Reject controls next to each changed block
• Ability to accept or reject individual hunks instead of approving an entire file
• Accept All / Reject All options
• Ideally, allow editing the proposed change before accepting it

This would make reviewing Codex-generated changes much faster and safer, especially when Codex makes multiple modifications and I only want to accept some of them.

2. Better context controls inside VS Code

It should be easier to explicitly control what is being sent as context to Codex.

Useful actions would include:

• Add current file to context
• Add currently selected code to context
• Add all currently opened files
• Add a folder to context
• Remove files from context
• Clearly display which files are currently included in the context

These actions should ideally be available through keyboard shortcuts, the editor context menu, and the Codex sidebar.

3. Persistent custom instructions

It would also be very useful to have an easy interface for defining instructions Codex should follow.

Examples:

• Coding style
• Framework conventions
• Architecture rules
• Testing requirements
• Preferred libraries
• Naming conventions
• Project-specific rules

It would be useful to support different scopes, such as:

• Global user instructions
• Workspace instructions
• Repository/project instructions

Overall, I think Codex is already very capable as a coding agent, but the VS Code extension could become much more comfortable and productive for developers if the interaction with code changes and context management felt more native to the editor.

Additional information

The workflow I have in mind is something like:

Codex proposes a change
→ the change appears inline inside the file
→ removed code is shown in red
→ added code is shown in green
→ I review each individual change
→ I accept or reject each hunk
→ I continue coding without leaving the editor

This kind of workflow is particularly useful when Codex makes several changes across a file but the developer only agrees with some of them.

I would also strongly value keyboard-first interactions, for example:

• Shortcut to add the current file to Codex context
• Shortcut to add the current selection
• Shortcut to open Codex with the current file already attached
• Quick actions for accepting or rejecting individual changes

The goal would be to make Codex feel deeply integrated into VS Code rather than having the developer frequently switch between the editor and a separate diff/review interface.

GitHub Copilot provides some useful UX patterns in this area, and I think Codex could benefit from similar ergonomics while keeping its stronger agentic capabilities.

The issue does not name implementation files, tests, or extension entry points. Begin by locating the Codex VS Code extension code and mapping the requested inline diffs, context controls, and persistent instruction scopes; define separate acceptance criteria and tests for each area before implementation.