This is a follow-up to https://github.com/openai/codex/pull/15922. That
previous PR deleted the old `tui` directory and left the new
`tui_app_server` directory in place. This PR renames `tui_app_server` to
`tui` and fixes up all references.
This is the part 1 of 2 PRs that will delete the `tui` /
`tui_app_server` split. This part simply deletes the existing `tui`
directory and marks the `tui_app_server` feature flag as removed. I left
the `tui_app_server` feature flag in place for now so its presence
doesn't result in an error. It is simply ignored.
Part 2 will rename the `tui_app_server` directory `tui`. I did this as
two parts to reduce visible code churn.
## Summary
- add shared `ModeKind` helpers for display names, TUI visibility, and
`request_user_input` availability
- derive TUI mode filtering/labels from shared `ModeKind` metadata
instead of local hardcoded matches
- derive `request_user_input` availability text and unavailable error
mode names from shared mode metadata
- replace hardcoded known mode names in the Default collaboration-mode
template with `{{KNOWN_MODE_NAMES}}` and fill it from
`TUI_VISIBLE_COLLABORATION_MODES`
- add regression tests for mode metadata sync and placeholder
replacement
## Notes
- `cargo test -p codex-core` integration target (`tests/all`) still
shows pre-existing env-specific failures in this environment due missing
`test_stdio_server` binary resolution; core unit tests are green.
## Codex author
`codex resume 019c26ff-dfe7-7173-bc04-c9e1fff1e447`
## Summary
This PR simplifies collaboration modes to the visible set `default |
plan`, while preserving backward compatibility for older partners that
may still send legacy mode
names.
Specifically:
- Renames the old Code behavior to **Default**.
- Keeps **Plan** as-is.
- Removes **Custom** mode behavior (fallbacks now resolve to Default).
- Keeps `PairProgramming` and `Execute` internally for compatibility
plumbing, while removing them from schema/API and UI visibility.
- Adds legacy input aliasing so older clients can still send old mode
names.
## What Changed
1. Mode enum and compatibility
- `ModeKind` now uses `Plan` + `Default` as active/public modes.
- `ModeKind::Default` deserialization accepts legacy values:
- `code`
- `pair_programming`
- `execute`
- `custom`
- `PairProgramming` and `Execute` variants remain in code but are hidden
from protocol/schema generation.
- `Custom` variant is removed; previous custom fallbacks now map to
`Default`.
2. Collaboration presets and templates
- Built-in presets now return only:
- `Plan`
- `Default`
- Template rename:
- `core/templates/collaboration_mode/code.md` -> `default.md`
- `execute.md` and `pair_programming.md` remain on disk but are not
surfaced in visible preset lists.
3. TUI updates
- Updated user-facing naming and prompts from “Code” to “Default”.
- Updated mode-cycle and indicator behavior to reflect only visible
`Plan` and `Default`.
- Updated corresponding tests and snapshots.
4. request_user_input behavior
- `request_user_input` remains allowed only in `Plan` mode.
- Rejection messaging now consistently treats non-plan modes as
`Default`.
5. Schemas
- Regenerated config and app-server schemas.
- Public schema types now advertise mode values as:
- `plan`
- `default`
## Backward Compatibility Notes
- Incoming legacy mode names (`code`, `pair_programming`, `execute`,
`custom`) are accepted and coerced to `default`.
- Outgoing/public schema surfaces intentionally expose only `plan |
default`.
- This allows tolerant ingestion of older partner payloads while
standardizing new integrations on the reduced mode set.
## Codex author
`codex fork 019c1fae-693b-7840-b16e-9ad38ea0bd00`
## Summary
Adds a simple `/plan` slash command in the TUI that switches the active
collaboration mode to Plan mode. The command is only available when the
`collaboration_modes` feature is enabled.
## Changes
- Add `plan_mask` helper in `codex-rs/tui/src/collaboration_modes.rs`
- Add `SlashCommand::Plan` metadata in
`codex-rs/tui/src/slash_command.rs`
- Implement and hard-gate `/plan` dispatch in
`codex-rs/tui/src/chatwidget.rs`
- Hide `/plan` when collaboration modes are disabled in
`codex-rs/tui/src/bottom_pane/slash_commands.rs`
- Update command popup tests in
`codex-rs/tui/src/bottom_pane/command_popup.rs`
- Add a focused unit test for `/plan` in
`codex-rs/tui/src/chatwidget/tests.rs`
## Behavior notes
- `/plan` is now a no-op if `Feature::CollaborationModes` is disabled.
- When enabled, `/plan` switches directly to Plan mode without opening
the picker.
## Codex author
`codex resume 019c05da-d7c3-7322-ae2c-3ca38d0ef702`
Keep an unmasked base collaboration mode and apply the active mask on
demand. Simplify the TUI mask helpers and update tests/docs to match the
mask contract.
## Summary
- Replace the plan‑implementation prompt with a standard selection
popup.
- “Yes” submits a user turn in Execute via a dedicated app event to
preserve normal transcript behavior.
- “No” simply dismisses the popup.
<img width="977" height="433" alt="Screenshot 2026-01-22 at 2 00 54 PM"
src="https://github.com/user-attachments/assets/91fad06f-7b7a-4cd8-9051-f28a19b750b2"
/>
## Changes
- Add a plan‑implementation popup using `SelectionViewParams`.
- Add `SubmitUserMessageWithMode` so “Yes” routes through
`submit_user_message` (ensures user history + separator state).
- Track `saw_plan_update_this_turn` so the prompt appears even when only
`update_plan` is emitted.
- Suppress the plan popup on replayed turns, when messages are queued,
or when a rate‑limit prompt is pending.
- Add `execute_mode` helper for collaboration modes.
- Add tests for replay/queued/rate‑limit guards and plan update without
final message.
- Add snapshots for both the default and “No”‑selected popup states.
- Only use collaboration modes in the tui state to track model and
effort.
- No behavior change without the collaboration modes flag.
- Change model and effort on /model, /collab (behind a flag), and
shift+tab (behind flag)