## Why
Pending Guardian review state could outlive an interrupted or completed turn,
leaving stale review details visible during a following goal turn.
## What changed
- Clear pending Guardian reviews during both turn completion and finalization.
- Restore an active MCP startup header after cleanup, falling back to `Working`
when no MCP server is starting.
## Testing
Added coverage for interrupted and completed turns, including goal continuation
and overlapping MCP startup status.
GitOrigin-RevId: a15ed81a5d6005e9294089f4424a8dedbc6e9cb5
## Why
MCP startup failures from spawned subagents were rendered as global
notifications, so a child thread's failure could pollute the visible
parent transcript. Routing the notification to the child exposed two
related replay problems: session refresh could discard the buffered
event, and a newly created child `ChatWidget` did not know the expected
MCP server set, which could leave its startup spinner running after
every server had settled.
MCP startup diagnostics should remain visible in the thread that owns
the startup without affecting other transcripts. The protocol also needs
to support a future app-scoped MCP lifecycle where startup is not owned
by any thread.
## Reported Behavior
The [originating Slack
report](https://openai.slack.com/archives/C08JZTV654K/p1780604538859939)
called out that using subagents could turn MCP startup failures into a
wall of yellow CLI warnings because repeated failures were not
deduplicated. The intended behavior is for those diagnostics to remain
visible once in the thread that owns the startup, without polluting the
parent transcript.
## What Changed
- add nullable `threadId` ownership to `mcpServer/startupStatus/updated`
- populate it from the app-server conversation ID for the current
thread-scoped lifecycle and regenerate the protocol schema and
TypeScript artifacts
- treat a missing or null `threadId` as app-scoped without injecting it
into the active chat transcript
- route and buffer thread-owned MCP startup notifications by thread in
the TUI
- preserve buffered MCP startup events across child session refresh
- seed expected MCP servers before replaying a thread snapshot so
startup reaches its terminal state
- suppress an identical repeated failure warning for the same server
within one startup round
The owning thread still renders the detailed failure and final `MCP
startup incomplete (...)` summary.
## How to Test
1. Configure an optional MCP server named `smoke` that exits during
initialization.
2. Launch the TUI with multi-agent support enabled.
3. Confirm the main thread's own startup failure renders one detailed
`smoke` warning and one incomplete-startup summary.
4. Spawn exactly one subagent.
5. Confirm the parent transcript does not receive the subagent's MCP
startup failure.
6. Switch to the subagent thread and confirm it contains exactly one
detailed `smoke` failure and one incomplete-startup summary.
7. Confirm the subagent's MCP startup spinner disappears and the thread
remains usable.
8. Switch between the parent and subagent and confirm the warnings
neither move nor duplicate.
Targeted tests:
- `just test -p codex-app-server-protocol`
- `just test -p codex-app-server
thread_start_emits_mcp_server_status_updated_notifications`
- `just test -p codex-tui mcp_startup`
The parent/child behavior and spinner completion were also exercised
manually in tmux. `just argument-comment-lint` was attempted but blocked
by an unrelated local Bazel LLVM empty-glob failure; touched Rust
callsites were inspected manually.
This change fixes the case where the UI can sit on _"Starting MCP
servers"_ even though the review work is already running or has already
completed.
- MCP startup status header is visible when a `/review` turn starts with
enabled MCP server startups
- Restore the underlying _Working..._ status after MCP startup completes
or fails
- Add regression coverage for overlapping startup/turn flows and status
restoration
_De-scoped from a broader thread-scoped MCP status change that would
have made it easier to route MCP startup statuses to the appropriate
thread (parent vs. review). These changes address the UI regression
without requiring more significant changes across app-server & core._
Fixes#18792.
## Why
With the local model layer and app-server routing in place from PR1,
this PR moves the active TUI runtime onto app-server notifications. The
affected pieces share the same event flow, so the command surface,
session state, bottom-pane prompts, chat rendering, history/status
views, and tests move together to keep the stacked branch buildable.
This PR also removes the obsolete compatibility surface that is no
longer used after the migration. The proposed protocol-boundary verifier
layer was dropped from the stack; enforcing that final boundary will be
simpler once `codex-tui` no longer needs any `codex_protocol`
references.
This PR is part 2 of a 2-PR stack:
1. Add TUI-owned replacement models and extract app-server event
routing.
2. Move the active TUI flow to app-server notifications and delete
obsolete adapter code.
## What changed
- Rewired app command and session handling to use app-server request and
notification shapes.
- Moved approval overlays, request-user-input flows, MCP elicitation,
realtime events, and review commands onto the app-server-facing model
surface.
- Updated chat rendering, history cells, status views, multi-agent UI,
replay state, and TUI tests to use app-server notifications plus the
local models introduced in PR1.
- Deleted `codex-rs/tui/src/app/app_server_adapter.rs` and the
superseded `chatwidget/tests/background_events.rs` fixture path.
## Verification
- `cargo check -p codex-tui --tests`
- Top of stack: `cargo test -p codex-tui`
## Why
This is part 1 of a 7-PR stack to remove direct
`codex_protocol::protocol` usage from `codex-tui` while keeping each
layer reviewable and shippable.
This first layer reduces the size of the later `chatwidget` diff by
mechanically moving MCP startup bookkeeping out of the central widget
file without changing the event shapes or behavior.
## What changed
- Extracted MCP startup status handling into
`tui/src/chatwidget/mcp_startup.rs`.
- Kept the existing core event types in place for this purely mechanical
move.
- Updated the MCP startup tests to import the moved test-only event
types directly.
## Verification
- `cargo test -p codex-tui chatwidget::tests::mcp_startup`
Eric Traut