## Summary
- reduce public module visibility across Rust crates, preferring private
or crate-private modules with explicit crate-root public exports
- update external call sites and tests to use the intended public crate
APIs instead of reaching through module trees
- add the module visibility guideline to AGENTS.md
## Validation
- `cargo check --workspace --all-targets --message-format=short` passed
before the final fix/format pass
- `just fix` completed successfully
- `just fmt` completed successfully
- `git diff --check` passed
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.
#### What
Add structured `@plugin` parsing and TUI support for plugin mentions.
- Core: switch from plain-text `@display_name` parsing to structured
`plugin://...` mentions via `UserInput::Mention` and
`[$...](plugin://...)` links in text, same pattern as apps/skills.
- TUI: add plugin mention popup, autocomplete, and chips when typing
`$`. Load plugin capability summaries and feed them into the composer;
plugin mentions appear alongside skills and apps.
- Generalize mention parsing to a sigil parameter, still defaults to `$`
<img width="797" height="119" alt="image"
src="https://github.com/user-attachments/assets/f0fe2658-d908-4927-9139-73f850805ceb"
/>
Builds on #13510. Currently clients have to build their own `id` via
`plugin@marketplace` and filter plugins to show by `enabled`, but we
will add `id` and `available` as fields returned from `plugin/list`
soon.
####Tests
Added tests, verified locally.
## What changed
- In `codex-rs/core/src/skills/injection.rs`, we now honor explicit
`UserInput::Skill { name, path }` first, then fall back to text mentions
only when safe.
- In `codex-rs/tui/src/bottom_pane/chat_composer.rs`, mention selection
is now token-bound (selected mention is tied to the specific inserted
`$token`), and we snapshot bindings at submit time so selection is not
lost.
- In `codex-rs/tui/src/chatwidget.rs` and
`codex-rs/tui/src/bottom_pane/mod.rs`, submit/queue paths now consume
the submit-time mention snapshot (instead of rereading cleared composer
state).
- In `codex-rs/tui/src/mention_codec.rs` and
`codex-rs/tui/src/bottom_pane/chat_composer_history.rs`, history now
round-trips mention targets so resume restores the same selected
duplicate.
- In `codex-rs/tui/src/bottom_pane/skill_popup.rs` and
`codex-rs/tui/src/bottom_pane/chat_composer.rs`, duplicate labels are
normalized to `[Repo]` / `[App]`, app rows no longer show `Connected -`,
and description space is a bit wider.
<img width="550" height="163" alt="Screenshot 2026-02-05 at 9 56 56 PM"
src="https://github.com/user-attachments/assets/346a7eb2-a342-4a49-aec8-68dfec0c7d89"
/>
<img width="550" height="163" alt="Screenshot 2026-02-05 at 9 57 09 PM"
src="https://github.com/user-attachments/assets/5e04d9af-cccf-4932-98b3-c37183e445ed"
/>
## Before vs now
- Before: selecting a duplicate could still submit the default/repo
match, and resume could lose which duplicate was originally selected.
- Now: the exact selected target (skill path or app id) is preserved
through submit, queue/restore, and resume.
## Manual test
1. Build and run this branch locally:
- `cd /Users/daniels/code/codex/codex-rs`
- `cargo build -p codex-cli --bin codex`
- `./target/debug/codex`
2. Open mention picker with `$` and pick a duplicate entry (not the
first one).
3. Confirm duplicate UI:
- repo duplicate rows show `[Repo]`
- app duplicate rows show `[App]`
- app description does **not** start with `Connected -`
4. Submit the prompt, then press Up to restore draft and submit again.
Expected: it keeps the same selected duplicate target.
5. Use `/resume` to reopen the session and send again.
Expected: restored mention still resolves to the same duplicate target.
