Files
codex/codex-rs/tui
T
Felipe Coury d3692b14c9 feat(tui): add clear-context plan implementation (#17499)
## TL;DR

- Adds a second Plan Mode handoff: implement the approved plan after
clearing context.
- Keeps the existing same-thread `Yes, implement this plan` action
unchanged.
- Reuses the `/clear` thread-start path and submits the approved plan as
the fresh thread's first prompt.
- Covers the new popup option, event plumbing, initial-message behavior,
and disabled states in TUI tests.

## Problem

Plan Mode already asks whether to implement an approved plan, but the
only affirmative path continues in the same thread. That is useful when
the planning conversation itself is still valuable, but it does not
support the workflow where exploratory planning context is discarded and
implementation starts from the final approved plan as the only
model-visible handoff.

<img width="1253" height="869" alt="image"
src="https://github.com/user-attachments/assets/90023d75-c330-4919-bed8-518671c3474b"
/>

## Mental model

There are now two implementation choices after a proposed plan. The
existing choice, `Yes, implement this plan`, is unchanged: it switches
to Default mode and submits `Implement the plan.` in the current thread.
The new choice, `Yes, clear context and implement`, treats the proposed
plan as a handoff artifact. It clears the UI/session context through the
same thread-start source used by `/clear`, then submits an initial
prompt containing the approved plan after the fresh thread is
configured.

The important distinction is that the new path is not compaction. The
model receives a deliberate implementation prompt built from the
approved plan markdown, not a summary of the previous planning
transcript. Both implementation choices require the Default
collaboration preset to be available, so the popup does not offer a
coding handoff when the fresh thread would fall back to another mode.

## Non-goals

This change does not alter `/clear`, `/compact`, or the existing
same-context Plan Mode implementation option. It does not add protocol
surface area or app-server schema changes. It also does not carry the
previous transcript path or a generated planning summary into the new
model context.

## Tradeoffs

The fresh-context option relies on the approved plan being sufficiently
complete. That matches the Plan Mode contract, but it means vague plans
will produce weaker implementation starts than a compacted transcript
would. The upside is that rejected ideas, exploratory dead ends, and
planning corrections do not leak into the implementation turn.

The current implementation stores the latest proposed plan in
`ChatWidget` rather than deriving it from history cells at selection
time. This keeps the popup action simple and deterministic, but it makes
the cache lifecycle important: it must be reset when a new task starts
so an old plan cannot be submitted later.

## Architecture

The TUI stores the most recent completed proposed-plan markdown when a
plan item completes. The Plan Mode approval popup uses that cache to
enable the fresh-context option and to build a first-turn prompt that
instructs the model to implement the approved plan in a fresh context.

Selecting the new option emits a TUI-internal
`ClearUiAndSubmitUserMessage` event. `App` handles that event by reusing
the existing clear flow: clear terminal state, reset app UI state, start
a new app-server thread with `ThreadStartSource::Clear`, and attach a
replacement `ChatWidget` with an initial user message. The existing
initial-message suppression in `enqueue_primary_thread_session` ensures
the prompt is submitted only after the new session is configured and any
startup replay is rendered.

## Observability

The previous thread remains resumable through the existing clear-session
summary hint. There is no new telemetry or protocol event for this path,
so debugging should start at the TUI event boundary: confirm the popup
emitted `ClearUiAndSubmitUserMessage`, confirm the app-server thread
start used `ThreadStartSource::Clear`, then confirm the fresh widget
submitted the initial user message after `SessionConfigured`.

## Tests

The Plan Mode popup snapshots cover the new option and preserve the
original option as the first/default action. Unit coverage verifies the
original same-context option still emits `SubmitUserMessageWithMode`,
the new option emits `ClearUiAndSubmitUserMessage` with the approved
plan embedded verbatim, and the clear-context option is disabled when
Default mode is unavailable or no approved plan exists. The broader
`codex-tui` test package passes with the updated fresh-thread
initial-message plumbing.
d3692b14c9 ยท 2026-04-17 14:30:09 -03:00
History
..