## Why
Paginated threads need explicit user-facing names to remain distinct from
derived titles and previews without requiring rollout metadata writes.
## What changed
- Add a nullable `name` column to persisted thread metadata and use it as the
canonical name for paginated threads.
- Route paginated name updates through the state database while retaining the
name index as best-effort compatibility data and preserving legacy thread
behavior.
- Return persisted names when reading, listing, searching, and resuming
paginated threads, and include them in state-database search matching.
## Testing
- Cover paginated name updates, reads, list/search results, and metadata-only
resume behavior, including stale or unavailable compatibility data.
GitOrigin-RevId: 5ac4dfa2a83682b43d59ecc87e0f515580164dca
## Why
Clients that use full-history resume or request full items in turn pages should
work consistently across legacy and paginated threads.
## What changed
- Materialize complete turns and items from the paginated projection for
`thread/resume` and `thread/turns/list` when requested.
- Support `initialTurnsPage` during paginated resume, including merging a live
active turn while preserving the requested page size and cursors.
- Keep metadata-only resume behavior and backwards cursors available through
`excludeTurns: true`.
## Testing
- Extend app-server coverage for full paginated history, full item views, and
initial resume pages on running threads.
GitOrigin-RevId: e340f44d631ce135895c95d7e1baa7bfecd86e71
## What changed
- Add the experimental `thread/searchOccurrences` app-server method for case-insensitive literal search across visible user messages and final assistant messages without replaying the thread.
- Return paginated snippets with UTF-16 match ranges and `thread/turns/list` cursors for navigating to each matching turn.
- Index persisted item types to efficiently select searchable messages from paginated thread history.
## Testing
- Add an app-server integration test covering pagination, steering messages, final-answer selection, Markdown normalization, and UTF-16 offsets.
GitOrigin-RevId: e80160e0f83eb4e5db8de862307085093bee362b
## Why
Multi-agent V2 spawned threads are controlled by their parent and reject direct
app-server input. The TUI should expose that ownership instead of presenting an
input flow that the server will reject.
## What changed
- Add the experimental `Thread.canAcceptDirectInput` capability for loaded
threads and populate it from the same policy used to validate `turn/start`
and `turn/steer`. Stored, unloaded threads report `null`.
- Carry the capability through TUI thread discovery, selection, startup, and
resume flows, with a compatibility fallback for older app servers.
- Present parent-owned threads as view-only, preserve drafts and queued input,
block agent-directed commands and settings shortcuts, and keep local
navigation and inspection commands available.
## Testing
- Cover V1 writable and V2 view-only spawned threads through selection and
resume.
- Cover composer submission paths, queued and initial input preservation,
allowed navigation commands, settings shortcuts, and the view-only UI.
GitOrigin-RevId: 495ad051249e5577fb0b0c1cc8c40a0998d04918
## What changed
- Allow `thread/start` to select experimental `historyMode: "paginated"` when the thread store supports turn and item pagination.
- Resume paginated threads with bounded model context and require `excludeTurns: true` instead of loading full history.
- Return `turnsBackwardsCursor` and `itemsBackwardsCursor` from `thread/resume` so clients can hydrate durable history through `thread/turns/list` and `thread/items/list` while newer records arrive through live notifications.
- Reject operations that still require full history, including `initialTurnsPage`, `thread/read` with `includeTurns: true`, `thread/rollback`, and detached review.
- Make item cursors independent of the optional `turnId` filter.
## Testing
- Cover paginated thread start, cold and live resume, backwards cursor hydration, metadata reads, unsupported operations, and stores without pagination support.
GitOrigin-RevId: c42f9b268e29d049843330f474fa3ecde12f5b8a
## What changed
- Add experimental `beforeTurnId` support to `thread/fork` for copying history strictly before a turn, including an in-progress turn.
- Use before-turn forks for TUI backtracking and safety retries so the replacement prompt retains thread context instead of recreating the branch from the preceding turn or a new thread.
- Add experimental `deferGoalContinuation` support so safety-retry forks can inherit an active goal while waiting for the replacement turn before automatic continuation resumes.
- Hide duplicated nested-review prompts when replaying history or selecting a prompt to edit.
## Testing
- Cover before-turn truncation, fork validation, active-goal inheritance, TUI safety retries, backtracking, and nested-review replay.
GitOrigin-RevId: 4915d85ae1929a0b8c40f3ed7dca29c7a5bdcdf3
## Why
Clients could discover threads with paginated history, but could not page their
turns through `thread/turns/list`.
## What changed
- Route `thread/turns/list` for paginated threads through the thread store,
preserving cursors, sort direction, turn status, timing, errors, and the
requested `summary` or `notLoaded` item view.
- Reject the `full` turn item view for paginated threads and direct clients to
`thread/items/list` for complete item pagination.
- Return each item page entry with both its containing `turnId` and `item`, so
clients can regroup thread-wide pages into turns.
- Expose local thread-store turn and item pagination through the `ThreadStore`
implementation.
## Testing
Added app-server coverage for paging projected turns and items, item views,
cursors, turn metadata, and rejection of the unsupported `full` view.
GitOrigin-RevId: 9c4a127a9b4fa91313f0e87494c62fe2e3a06f19
## What changed
- Check the source thread's `history_mode` before loading its history for
`thread/fork`.
- Return the existing `paginated_threads is not supported yet` method-not-found
error for paginated source threads.
## Testing
- Add an app-server integration test covering rejection of a paginated source
thread.
GitOrigin-RevId: 49b4b8aef7c9488eec93c24e831cea6382f8c995
## Why
Multi-environment turns can run against different filesystems, so a single
thread-wide workspace-root list cannot accurately describe every selected
environment.
## What changed
- Add optional `runtimeWorkspaceRoots` to each app-server environment selection.
Omitted roots default to that environment's `cwd`, while an empty list selects
no roots.
- Carry environment-native roots through turn selection, model-visible context,
permission materialization, and tool sandboxing.
- Keep the top-level `runtimeWorkspaceRoots` field as a compatibility input when
constructing default environment selections; explicit selections use their
own roots.
## Testing
- Cover thread and turn API defaults, overrides, empty roots, and schema
round-tripping.
- Verify foreign roots remain model-visible and remote execution applies the
target environment's roots before sandbox selection.
GitOrigin-RevId: c6e7a62883c45c676c153055f46a55ee15a323a4
## What changed
- Project durable paginated rollout records into rebuildable SQLite tables for turns, items, and projection progress while keeping JSONL as the source of truth.
- Add cursor-based local reads for turn summaries and thread or per-turn items, including archived-thread and history-mode validation.
- Serialize writes, shutdown, and deletion per thread so projection updates cannot race cleanup, and remove projected rows when a thread is deleted.
- Preserve stable item ordering while updating repeated snapshots and expose structured turn error details.
## Testing
- Cover projection, snapshot updates, summary recovery, pagination, failure handling, shutdown flushing, legacy-mode rejection, and deletion races.
GitOrigin-RevId: 34533185ece7f1f5690004c7f12b0f1f34dc2640
## Why
`Max` and `Ultra` consume usage limits faster than standard reasoning levels, so they should not be selected accidentally while navigating the normal effort scale.
## What changed
- Move `Max` and `Ultra` behind a `More reasoning…` entry with a dedicated warning and descriptions.
- Keep the reasoning shortcuts from silently increasing into advanced efforts.
- Apply `Ultra` to the active conversation without changing defaults for new threads, while preserving it across mode switches and thread resumes.
- Record applied thread settings in thread metadata, including explicit clearing of reasoning effort, so resumed threads restore their latest model settings unless the user supplied an override.
## Testing
- Add TUI coverage for the advanced picker, shortcuts, Plan mode, configuration defaults, and resumed conversations.
- Add app-server and thread-store coverage for persisting, clearing, and restoring model and reasoning settings.
GitOrigin-RevId: 6708c7c2e8d38f491bf63000ea34f83476afdfe6
## What changed
- Allow the local thread store to create paginated threads while keeping them unsupported through the app-server API.
- Filter live append items using the history mode recorded with the thread's live recorder, so paginated threads persist canonical `ItemCompleted` events instead of legacy history events.
## Testing
- Add a local-store test that creates a paginated thread and verifies that a paginated item is persisted while a legacy user-message event is omitted.
GitOrigin-RevId: 83d93660afd5f0217213d4f21b5bf2a97745ff19
## Description
This PR makes new threads with `history_mode = "paginated"` persist
`ItemCompleted(item: <turn_item>)` in their rollout JSONL file.
Legacy threads keep persisting the existing legacy events. Because the
format is selected per thread, a rollout is either legacy or paginated;
we do not need to support mixed rollouts containing both
representations.
This PR depends on [#31473](https://github.com/openai/codex/pull/31473).
## Why
Paginated thread history needs stable turn/item IDs and completed item
snapshots so the later SQLite projector can materialize appended rollout
JSONL without rebuilding the whole thread.
Keeping the legacy persistence policy unchanged avoids changing
historical rollouts or the readers that still consume them.
## What changed
- Made rollout filtering history-mode aware. Paginated threads keep
completed canonical `ItemCompleted` events and drop their redundant
legacy projections; legacy threads keep the existing event set.
- Made forks inherit the source thread history mode, so copied legacy
history is never filtered as paginated.
- Made paginated threads assign IDs to locally-created response items
even when `Feature::ItemIds` is off, and reject streamed output items
that arrive without server IDs.
- Updated legacy turn replay, rollout list/search, and SQLite metadata
extraction to understand completed canonical user-message items.
## Why
A thread resumed without an explicit reviewer could pick up the reviewer
from the current config instead of preserving the reviewer already in
use by the thread. After an app restart, this meant a thread running
with auto review could silently switch back to user review, and the next
turn could continue under the wrong reviewer.
## What changed
Persist the effective reviewer with each turn and restore the latest
persisted value when the thread resumes. If the resume request
explicitly provides a reviewer, that value still takes precedence.
## Test plan
- Added a regression test that starts a thread with auto review, records
a turn, restarts with user review in config, resumes without an
override, and verifies that auto review is preserved.
- `just test -p codex-protocol`
- `just test -p codex-state`
- `just test -p codex-rollout`
- `just test -p codex-app-server
thread_resume_preserves_persisted_approvals_reviewer`
- Clippy for the affected crates
## Why
App-server initialization captures exec-policy parse warnings only once.
Each `thread/start` then reloads config for that thread's cwd and
rereads its `.rules` files, so rules that become malformed after
initialization—or belong to a different project—are dropped without a
fresh warning to the requesting client.
## What changed
- Validate exec-policy rules against the freshly loaded per-thread
config during `thread/start`.
- Send the existing structured `configWarning` only to the connection
that requested the thread.
- Preserve nonfatal startup and avoid repeating an identical warning
already delivered during initialization.
This is intentionally separate from the TUI `legacy_core` cleanup in
#31179 and the managed-requirements fallback fix in #31188.
## Description
This adds stable optional `turnId` support to `thread/fork`. When
supplied, the fork copies persisted history through that terminal turn,
inclusive, and drops later turns from the new thread.
Omitting or passing `null` preserves the existing full-history fork
behavior, including the interruption marker when the stored source
history ends mid-turn.
## Why
We're deprecating `thread/rollback` and this will help certain UX use
cases work around it by using `thread/fork` + `turn_id` instead.
## Description
This PR adds a new `historyMode = "legacy" | "paginated"` to `Thread`.
This will be stored in `SessionMeta` in the JSONL rollout file and as a
new column in the SQLite thread_metadata table, and exposed on
`thread/start` and on the `Thread` object in app-server.
## What changed
- Added canonical `ThreadHistoryMode` with `legacy` and `paginated`,
defaulting old and new SessionMeta to `legacy`.
- Carried `history_mode` through core session config, ThreadStore stored
metadata, local/in-memory stores, rollout metadata extraction, and the
existing SQLite `threads` table.
- Added experimental `historyMode` to app-server v2 `Thread` and
`thread/start`.
- Made paginated stored threads metadata-discoverable but unsupported
for legacy full-history reads, `load_history`, live resume, and create
paths.
- Regenerated app-server schema fixtures and added
protocol/state/thread-store/app-server coverage for persistence and
fail-closed behavior.
## Compatibility floor
Because users may be running various versions of Codex binaries on the
same machine (TUI, Codex App, etc.), we will need to establish a
compatibility floor for upcoming paginated threads, which will change
how thread storage reads and writes work.
The overall plan here:
```
Release N:
- Add historyMode to SessionMeta / Thread / SQLite metadata.
- Teach binaries to understand paginated threads.
- If a binary sees `historyMode="paginated"` but does not support the paginated contract, it refuses to resume/mutate the thread.
- Default remains `"legacy"`.
Release N+1:
- First-party clients start opting into paginated threads where appropriate.
- Internal dogfood / staged rollout.
- Measure old-client usage and paginated-thread unsupported errors.
Release N+2:
- Only after Release N+ is overwhelmingly deployed, make paginated the default.
- Accept that a small tail of N-1-or-older binaries may not understand paginated threads.
```
The important behavior change is fail-closed handling for a binary that
encounters a persisted `paginated` thread before it knows how to fully
support paginated history. In app-server, if a thread is `paginated`, we
will:
- allow metadata-only discovery paths like `thread/list` and
`thread/read(includeTurns=false)`, so clients can still see the thread
and inspect its `historyMode`
- reject legacy full-history/live-thread paths like
`thread/read(includeTurns=true)` and `thread/resume` with an unsupported
JSON-RPC error
- avoid silently treating an unknown or future `historyMode` as `legacy`
Under the hood, the ThreadStore layer also rejects legacy operations
that would need to load or replay the full thread history for a
paginated thread. That gives us the behavior we want for Release N:
future paginated threads are visible, but this binary fails closed
instead of trying to operate on them as if they were legacy threads.
## Why
Desktop Work threads and regular Codex threads can share the same
app-server connection. App-server analytics currently copy
`product_client_id` from connection metadata for every thread-scoped
event, so Work thread activity is attributed to the Desktop connection
instead of the thread's resolved originator. This prevents analytics
from distinguishing the two products on a shared connection.
## What changed
- Publish the resolved originator after a thread is materialized,
covering new, resumed, forked, and subagent threads.
- Store that originator in the analytics reducer's existing per-thread
state.
- Override only `app_server_client.product_client_id` for thread, turn,
tool, review, goal, guardian, and compaction events while preserving the
connection's client name, version, and transport metadata.
- Fall back to the connection-wide product client ID when a thread has
no originator override.
- Preserve persisted originators in thread initialization analytics for
resume and fork flows.
## Validation
- `just test -p codex-analytics
thread_originator_overrides_shared_connection_across_thread_events
subagent_events_keep_thread_originator_with_explicit_turn_connection`
- `just test -p codex-app-server
turn_start_tracks_thread_originator_in_analytics
thread_start_tracks_thread_initialized_analytics
thread_fork_tracks_thread_initialized_analytics
thread_resume_tracks_thread_initialized_analytics`
- `just test -p codex-core thread_manager`
## Why
Selected plugin metadata is stable, but MCP processes are live runtime
state. They need different lifetimes:
- the MCP extension caches manifest, MCP, and connector declarations for
each stable selected root;
- each model step projects that cached metadata through the roots that
resolved as ready for that exact step;
- the MCP manager is rebuilt only when that availability projection
changes.
This matches executor skills: both features consume the same resolved
step roots instead of inferring readiness from the turn's selected
environments.
## Behavior
```text
E1 not ready for this step
-> no E1 MCP servers or connectors
-> cached plugin metadata stays in ext/mcp
E1 becomes ready
-> reuse cached metadata
-> publish one MCP runtime containing E1 capabilities
same ready roots on the next step
-> reuse the exact runtime; no rediscovery and no MCP restart
resume
-> create new extension thread state and a new MCP runtime
```
All model-facing consumers use the same step snapshot:
```text
resolved selected roots
|
v
extension MCP/connector projection
|
v
{ MCP config, connector snapshot, MCP manager }
|
+-> advertise model tools
+-> build app/connector tools
+-> execute MCP calls
```
## Cache contract
The existing MCP extension owns a cache keyed by the full
`SelectedCapabilityRoot`:
```rust
let state = thread_store.get_or_init(SelectedExecutorPluginMcpState::default);
```
The cache lives with extension thread state. Environment availability
filters projection but does not invalidate metadata. Resume creates new
thread state. There is no file watcher or executor generation because
contents behind a stable environment/root are assumed stable.
## What changes
- Keeps executor plugin discovery and cached metadata in `ext/mcp`.
- Caches MCP and connector declarations together per selected root.
- Uses the step's already-resolved capability roots, including lazy
environments that are not turn environments.
- Reuses the current MCP runtime when the ready-root projection is
unchanged.
- Uses the same step MCP manager and connector snapshot for
model-visible tools and execution.
- Resolves direct thread-scoped MCP requests from the current
selected-root projection.
## Deliberately out of scope
- `app/list` remains based on the latest global host-plugin state; this
PR does not make its response or notifications thread-specific.
- `required = true` startup semantics do not apply to delayed executor
MCP activation.
- No filesystem/content invalidation.
- No transport-disconnect watcher.
- No executor generations or environment replacement semantics.
- No client sharing across complete manager replacements.
## Stack
1. Extension-owned World State sections.
2. Project executor skills through World State.
3. Pin one MCP runtime to each model step.
4. **This PR:** project selected MCP and connector state from
extension-owned metadata.
5. Integration coverage for selected capability availability and resume.
## Verification
-
`selected_plugin_servers_use_managed_requirements_for_the_selected_root_id`
- The stacked integration PR covers unavailable to ready activation,
unchanged-runtime reuse, skills, MCP tools, connector attribution, and
cold resume.
## Why
The TUI uses `thread/rollback` internally for user-facing flows such as
prompt cancellation/backtracking. After `thread/rollback` was marked
deprecated, those internal calls started surfacing `deprecationNotice`
messages in the TUI, even though the user did not explicitly call the
deprecated app-server API.
The endpoint should remain deprecated for external app-server clients,
but the built-in `codex-tui` client should not show this
implementation-detail warning during normal interaction.
## What changed
- Pass the initialized app-server client name into the `thread/rollback`
request processor.
- Suppress the `thread/rollback` deprecation notice only for
`codex-tui`.
- Preserve the existing `deprecationNotice` behavior for non-TUI
clients.
- Add regression coverage for the `codex-tui` suppression path.
## How to Test
1. Start Codex TUI from this branch.
2. Type text into the composer and press `Esc` to cancel/backtrack.
3. Confirm the TUI restores/cancels the prompt without showing
`thread/rollback is deprecated and will be removed soon`.
4. Also verify an external app-server client that calls
`thread/rollback` still receives `deprecationNotice`.
Targeted tests:
- `just test -p codex-app-server thread_rollback`
- `just argument-comment-lint`
## Why
Helper threads such as task title generation can request a model ID that
is valid for the default OpenAI provider but unavailable from the active
provider. With Amazon Bedrock, `gpt-5.4-mini` is rejected while the
provider static catalog exposes Bedrock model IDs such as
`openai.gpt-5.5` and `openai.gpt-5.4`. This causes repeated background
404s and can surface a misleading turn error even when the main turn
succeeds.
Clients need an explicit way to ask app-server to resolve an unavailable
helper model to the active provider default. That fallback must remain
limited to providers with an authoritative static catalog so custom or
dynamically discovered model IDs are not rewritten based on an
incomplete catalog.
Fixes#28741.
## What changed
- Add the experimental `allowProviderModelFallback` option to
`thread/start`, defaulting to `false` to preserve existing behavior.
- Thread the option through thread creation and model selection.
- When enabled for a static model manager, preserve requested models
present in the catalog and replace unavailable models with the provider
default.
- Continue preserving explicit model IDs for dynamic model managers
without fetching a catalog solely to validate them.
- Document the new `thread/start` behavior in the app-server API
overview.
## Test
Temporary test-client harness:
```
ThreadStartParams {
model: Some("gpt-5.4-mini".to_string()),
allow_provider_model_fallback: true,
..Default::default()
}
```
Command:
```
CODEX_HOME=/tmp/codex-bedrock-thread-start-home \
CODEX_E2E_BEDROCK_THREAD_START_ONLY=1 \
./target/debug/codex-app-server-test-client \
--codex-bin ./target/debug/codex \
-c 'model_provider="amazon-bedrock"' \
send-message-v2 --experimental-api ignored
```
Relevant output:
```
> "method": "thread/start",
> "params": {
> "model": "gpt-5.4-mini",
> "modelProvider": null,
> "allowProviderModelFallback": true,
> ...
> }
< "result": {
< "model": "openai.gpt-5.5",
< "modelProvider": "amazon-bedrock",
< ...
< }
```
## Why
Ultra should be one user-facing reasoning selection for work that
benefits from both maximum reasoning and proactive multi-agent
delegation. Without it, clients must coordinate maximum reasoning with
the experimental `multiAgentMode` setting, even though the inference
backend still expects its existing `max` effort value.
This change makes reasoning effort the source of truth: clients select
`ultra`, core derives proactive multi-agent behavior when the turn is
eligible for multi-agent V2, and inference requests continue to use the
backend-compatible `max` value.
## What changed
- Add `ultra` as a first-class reasoning effort and preserve
model-catalog ordering when exposing it to clients.
- Convert `ultra` to `max` at the inference request boundary, including
Responses HTTP/WebSocket requests, startup prewarm, compaction, and
memory summarization.
- Derive effective multi-agent mode per turn from effective reasoning
effort:
- eligible multi-agent V2 + `ultra` → `proactive`
- eligible multi-agent V2 + any other effort → `explicitRequestOnly`
- V1 or otherwise ineligible sessions → no multi-agent mode instruction
- Keep the derived effective mode in turn context history so successive
turns can emit a developer-message update only when the effective mode
changes.
- Remove selected multi-agent mode from core session configuration, turn
construction, thread settings, resume/fork restoration, and subagent
spawn plumbing. Subagents inherit reasoning effort and derive their own
effective mode.
- Retain the experimental app-server `multiAgentMode` fields for wire
compatibility while marking them deprecated. Request values are accepted
but ignored; compatibility response fields report `explicitRequestOnly`.
- Display Ultra in the TUI using the order supplied by `model/list`.
## Validation
- `just test -p codex-core ultra_reasoning_uses_max_for_requests`
- `just test -p codex-tui model_reasoning_selection_popup`
Pick up the AgentGraphStore migration.
- Inject an explicit optional agent graph store into `ThreadManager`
- Move all calls to spawn, close, recursive resume, and
subtree/archive/delete/feedback traversal through it
- Keep using `LocalAgentGraphStore` when SQLite is available
This required some changes to the interface to deal with futures:
- The interface now matches `ThreadStore`'s object-safe pattern by
returning a boxed `AgentGraphStoreFuture` directly, allowing
`ThreadManager` to hold `Arc<dyn AgentGraphStore>`
*Slight behavior change!* Unfiltered subtree enumeration now performs a
single all-status breadth-first traversal, so a closed grandchild
beneath an open edge is included; the previous Open-then-Closed
traversals could not cross mixed-status paths and silently omitted it.
## Why
`thread/list` can filter direct children with `parentThreadId`, but
clients cannot request an entire spawned subtree. Discovering every
descendant requires repeated client-side requests and gives up the
database's existing filtering and pagination path.
## What changed
Experimental clients can use `ancestorThreadId` to return strict
descendants at any depth while `parentThreadId` retains its direct-child
meaning. The filters are mutually exclusive, the ancestor is excluded,
and every result preserves its immediate `parentThreadId` so callers can
reconstruct the tree.
## How it works
- **Explicit relationship:** Internal list parameters distinguish direct
children from transitive descendants without changing the meaning of
`parentThreadId`.
- **Existing graph:** Persisted parent-child spawn edges remain the
source of truth, so descendant lookup needs no schema migration or
ancestry cache.
- **Indexed traversal:** A recursive SQLite query starts from the
parent-edge index, walks each generation, and applies thread filters,
sorting, and cursor pagination in the same database request.
- **Reconstructable results:** The response stays flat and normally
ordered while carrying each descendant's immediate parent.
## Verification
Ran 550 tests across the protocol, state, rollout, and thread-store
crates, then reran the four focused state, store, and app-server
descendant-listing tests after the final diff reduction. Scoped Clippy
and formatting checks passed. Stable and experimental schema generation
was checked; the stable fixtures remain unchanged while the experimental
schema includes the new field.
## Description
Rename the experimental app-server item pagination API from
`thread/turns/items/list` to `thread/items/list` and make `turnId`
optional. Clients can now page persisted items across a thread, or still
filter to one turn when needed.
## What changed
- Rename the request/response protocol types and JSON-RPC method to
`ThreadItemsList*` / `thread/items/list`.
- Pass optional `turnId` through to `ThreadStore::list_items`.
- Update app-server docs and focused protocol/app-server tests.
## Validation
- `just test -p codex-app-server-protocol thread_items_list_round_trips`
- `just test -p codex-app-server thread_items_list_returns_unsupported`
## Summary
Resuming a persisted thread currently deep-clones its complete rollout
history several times. `InitialHistory` is retained for the app-server
response, copied into thread persistence, and copied again by read-only
accessors. These copies scale with the complete rollout rather than the
bounded model context and add measurable latency for large sessions.
This change stores resumed rollout history in `Arc<Vec<RolloutItem>>`.
Rollout loading wraps the parsed vector once, while app-server response
construction, session initialization, and thread persistence share it
through inexpensive `Arc` clones. Read-only history access now returns a
borrowed slice, and fork paths use `Arc::unwrap_or_clone` where they
genuinely need mutable ownership. Rollout reconstruction also consumes
its temporary context instead of cloning the reconstructed model
history.
The serialized representation remains unchanged. In an artificial 123 MB
rollout benchmark, sharing resumed history reduced cold resume latency
by roughly 9–10%. The affected crates compile with their test targets,
all 80 thread-store tests pass, and the Bazel dependency lock remains
valid.
## Why
Once multi-agent mode can be selected per turn, clients also need to
choose the initial selection when creating a thread and observe that
selection through lifecycle and settings APIs.
The selected value is intentionally distinct from the effective
model-visible value: no client selection is represented as `null`, even
though an eligible multi-agent v2 turn derives `explicitRequestOnly` as
its effective default.
## What changed
- Add the optional experimental `thread/start.multiAgentMode` parameter
and pass it through thread creation.
- Preserve an omitted initial value as an unset selection rather than
eagerly storing `explicitRequestOnly`.
- Apply an explicit `thread/start` selection to the first turn through
the session configuration established at thread creation.
- Restore the latest persisted effective mode as the selected baseline
on cold resume when rollout history contains one.
- Inherit the optional selected mode from a loaded parent when creating
related runtime threads.
- Return the current selected `multiAgentMode` from `thread/start`,
`thread/resume`, `thread/fork`, and thread settings, using `null` when
no mode is selected.
- Keep lifecycle reporting independent from model capability and feature
eligibility; core turn construction remains responsible for calculating
and persisting the effective mode.
## Not covered
- Clearing an existing loaded-session selection back to unset through
`turn/start`; omitted or `null` currently retains the session's
selection.
- A TUI control, slash command, or `config.toml` preference.
## Verification
- `CARGO_INCREMENTAL=0 just test -p codex-app-server-protocol`
- `CARGO_INCREMENTAL=0 just test -p codex-app-server multi_agent_mode`
The focused app-server coverage verifies explicit `thread/start`
initialization, first-turn prompting, nullable reporting for an omitted
selection, and retention of selections that are not currently
runtime-eligible.
## Stack
Stacked on #28685. This PR contains only the thread initialization and
lifecycle/settings API layer.
## Why
Make it possible to load AGENTS.md from remote exec-servers whose OS is
different than app-server.
## What
- keep `AGENTS.md` discovery and provenance as `PathUri`, with
root-aware parent and ancestor traversal
- expose lifecycle instruction sources as legacy app-server path strings
in events while retaining `PathUri` internally
- preserve and test mixed POSIX and Windows paths in model context and
TUI status output
- cover remote Windows loading end to end by seeding the Wine prefix
through host filesystem APIs
- fix bug in `PathUri`'s parent() implementation that would erase
Windows drive letters
## Why
It should be possible for app-server to handle "foreign" OS paths in
unified_exec working directories, allowing e.g. a Linux app-server to
run processes on e.g. a Windows exec-server.
## What
Convert the core unified_exec cwd values to use `PathUri`.
Adds fallible path conversion in several places to try to minimize the
scope of this change. The only time this change suppresses errors from
converting `PathUri` to an `AbsolutePathBuf` is when the turn is
configured with no sandboxing at all to allow us to make progress
testing without sandboxing.
Future changes to apply_patch and sandboxing will clean up these error
paths.
A tool's cwd is resolved from joining a model-provided workdir to the
environment's cwd. When using `AbsolutePathBuf::join()`, an
absolute-path workdir would overwrite the environment's cwd and we would
resolve permissions/sandboxing against the model-provided path. This
change extends `PathUri::join()` to also treat an absolute rhs as an
override of the base/lhs.
This also removes some coverage from the remove_env_windows tests until
a follow-up converts foreign paths in command exec events correctly.
## Breaking Changes
When using `AbsolutePathBuf::join()` for workdir resolution, we ended up
resolving tilde-prefixed paths against the app-server's `$HOME`, e.g.
`~/foo/bar` becomes `/home/anp/foo/bar`. It's difficult to do this with
`PathUri` joining, so after offline discussion this PR no longer
implements it.
A quick check of some power users' rollouts suggests that models don't
actually generate home-prefixed absolute working directories for their
spawns, so this shouldn't have any real blast radius.
## Summary
- Revert #28655, restoring the thread `recencyAt` behavior introduced by
#27910.
- Move `threads_recency_at` to migration 0039 so it no longer collides
with `external_agent_config_imports` at version 0038.
- Repair databases that already applied the recency migration as version
38 by moving the matching migration-history row to version 39 before
SQLx validation. The current version-38 migration can then apply
normally.
## Validation
- `just test -p codex-state
migrations::tests::repairs_recency_migration_that_was_applied_as_version_38`
- `just test -p codex-state -p codex-rollout -p codex-thread-store -p
codex-app-server-protocol -p codex-tui`: 3,439 passed; six TUI tests
could not open the machine's existing read-only incident database at
`~/.codex/sqlite/state_5.sqlite`.
- `just fix -p codex-state`
- `just fmt`
- Verified that state migration versions are unique.
## Why
Revert #27910 to remove the newly introduced thread `recencyAt`
persistence and API behavior from `main`.
## What changed
This reverts commit `fac3158c2a783095768076489815f361fa9b0db4`,
including the state migration, thread-store propagation, app-server API
surface, generated schemas, and related tests.
## Validation
Not run before opening; relying on CI for the initial fast signal.
## Summary
Add a server-owned `recencyAt` timestamp and `recency_at` thread-list
sort key for product recency ordering while preserving the existing
meaning of `updatedAt` as the latest persisted thread mutation.
This is the server-side alternative to #27697. Rather than narrowing
`updatedAt`, clients can sort the sidebar by `recency_at` and continue
treating `updatedAt` as mutation time.
Paired Codex Apps PR:
[openai/openai#1024599](https://github.com/openai/openai/pull/1024599)
## Contract
- `recencyAt` initializes when a thread is created.
- A turn start advances `recencyAt` monotonically.
- Commentary, agent output, tool results, token/accounting updates, turn
completion, archive, unarchive, resume, and generic metadata writes do
not advance it.
- `updatedAt` retains its existing behavior and continues to advance for
persisted thread mutations.
- Current servers populate `recencyAt`; the response field is optional
in generated TypeScript so clients connected to older servers can fall
back to `updatedAt`.
- Filesystem-only fallback uses existing updated/mtime ordering when
SQLite is unavailable.
## Persistence and compatibility
Migration 0038 adds second- and millisecond-precision recency columns,
backfills them from the existing updated timestamp, creates list
indexes, and includes an insert trigger so older binaries writing to a
migrated database seed recency without causing later mutations to
advance it.
Generic metadata upserts preserve existing recency values. Turn-start
updates use a dedicated monotonic touch, and process-local allocation
keeps millisecond cursor values unique. State DB list, search, read,
filtered-list repair, rollout fallback propagation, and app-server
conversions all carry the new field.
## API
`Thread` responses include:
```ts
recencyAt?: number
```
`thread/list` and `thread/search` accept:
```json
{ "sortKey": "recency_at" }
```
Generated TypeScript and JSON schemas are included.
## Validation
- `just test -p codex-state` — 146 passed
- `just test -p codex-rollout` — 69 passed
- `just test -p codex-thread-store` — 81 passed
- `just test -p codex-app-server-protocol` — 231 passed
- Focused app-server list ordering, response mapping, archive/unarchive,
and resume lifecycle tests passed
- Scoped `just fix` for state, rollout, thread-store,
app-server-protocol, and app-server
- `just fmt`
- `git diff --check`
- Independent correctness, simplicity, elegance, security, and
test-quality reviews; actionable ordering, lifecycle, query-projection,
and timestamp-uniqueness findings were addressed
## Why
app-server may run on a different OS from the selected exec-server
environment. Parsing that environment’s cwd with the Codex host’s path
rules prevents thread startup.
## What
Carry environment cwd values as `LegacyAppPathString` at the app-server
boundary and `PathUri` internally. Existing tool-call schemas and
relative-path behavior stay host-native; remaining local-only consumers
convert explicitly and leave follow-up TODOs.
The Wine integration test verifies app-server can start a thread and
complete an ordinary turn with a Windows environment cwd from Linux.
## Validation
- `bazel test //codex-rs/core/tests/remote_env_windows:smoke-test
--test_output=errors`
- focused app-server environment-selection and protocol schema tests
- scoped Clippy for `codex-core` and `codex-app-server-protocol`
Stacked on #27365.
## Stack note
[#27365](https://github.com/openai/codex/pull/27365) kept `thread/start`
unchanged and converted its input in `thread_processor`. This PR updates
`thread/start` to accept explicit functions and namespaces directly.
Legacy per-tool arrays are still accepted and converted while reading
the request. As a result, `thread_processor` can validate and pass the
tools through directly, which is why some code added in #27365 is
removed here.
## Why
`thread/start.dynamicTools` still repeats namespace data on each
function even though core now stores explicit namespace groups. The
request API should use the same shape so each namespace has one
description and one member list.
## What changed
- Accept top-level functions and explicit namespace objects in
`dynamicTools`.
- Continue accepting fully legacy flat arrays, including
`exposeToContext`.
- Reject arrays that mix legacy and canonical entries.
- Reuse the protocol types directly and remove the temporary app-server
adapter.
- Update validation, docs, the test client, and generated schemas.
## Test plan
- `just test -p codex-app-server-protocol`
- `just test -p codex-app-server
dynamic_tool_call_round_trip_sends_text_content_items_to_model`
- `just test -p codex-app-server
thread_start_normalizes_legacy_dynamic_tools_into_model_request`
- `just test -p codex-app-server
thread_start_rejects_mixed_dynamic_tool_formats`
- `just test -p codex-app-server
thread_start_rejects_hidden_dynamic_tools_without_namespace`
Follow-up to #27356.
## Stack note
This PR changes Codex's internal dynamic-tool shape while leaving
`thread/start` unchanged. App-server therefore converts the existing
per-tool input into explicit functions and namespaces before passing it
to core.
[#27371](https://github.com/openai/codex/pull/27371) updates
`thread/start` to use the same explicit shape and removes this temporary
conversion.
## Why
Dynamic tools repeat namespace metadata on every function. Core should
keep one explicit namespace with its member tools so descriptions and
membership stay consistent across sessions and runtime planning.
## What changed
- Represent dynamic tools as top-level functions or explicit namespaces
in protocol and session state.
- Read old flat rollout metadata and write the canonical hierarchy.
- Flatten namespace members only when registering callable tools.
- Keep `thread/start.dynamicTools` flat for now and normalize it at the
app-server boundary.
New builds can read old rollout metadata. Older builds cannot read newly
written hierarchical metadata.
## Test plan
- `just test -p codex-app-server
thread_start_normalizes_legacy_dynamic_tools_into_model_request`
- `just test -p codex-protocol
session_meta_normalizes_legacy_dynamic_tools`
- `just test -p codex-core
resume_restores_dynamic_tools_from_rollout_with_sqlite_enabled`
- `just test -p codex-core
tool_search_returns_deferred_dynamic_tool_and_routes_follow_up_call`
- `just test -p codex-core code_mode_can_call_hidden_dynamic_tools`
- `just test -p codex-tools`
## Why
#27870 teaches the MCP extension how to discover stdio MCP servers
declared by a selected executor plugin, but app-server does not yet
install that contributor or initialize its per-thread state. As a
result, `thread/start.selectedCapabilityRoots` can select the plugin
while its MCP servers remain inactive.
This PR closes that app-server wiring gap:
```text
thread/start(selectedCapabilityRoots)
-> initialize the thread's selected-plugin MCP snapshot
-> read the selected plugin's .mcp.json through its environment
-> start declared stdio servers in that environment
-> expose their tools only on the selected thread
```
## What changed
- Install the selected-executor-plugin MCP contributor in app-server
using the existing shared `EnvironmentManager`.
- Initialize its frozen thread snapshot when `thread/start` includes
selected capability roots.
- Document that selected plugin stdio MCPs are activated in their owning
environment.
- Add an app-server E2E covering the complete selection-to-tool-call
path.
The E2E verifies that:
- the selected MCP process receives an executor-only environment value,
proving the tool runs through the selected environment;
- the MCP tool is advertised to the model and can be called;
- a normal MCP config reload does not discard the thread's frozen
selected-plugin registration;
- another thread without the selected root does not see the MCP server.
## Scope
- Existing sessions without `selectedCapabilityRoots` are unchanged.
- Only stdio MCP declarations are activated. HTTP declarations remain
inactive.
- This does not change selected-root persistence across resume/fork or
add hosted-plugin behavior.
## Verification
- Focused app-server E2E:
`selected_executor_plugin_exposes_its_stdio_mcp_only_to_that_thread`
## Stack
Stacked on #27870.
## Why
Clients that display or coordinate spawned subagents need an
authoritative snapshot of a thread's immediate spawned children when
they connect to app-server or recover after missing live events.
`thread/list` cannot query by parent, so clients must otherwise scan
unrelated threads or reconstruct relationships from rollout history and
transient events.
The direct spawn relationship already exists in persisted
`thread_spawn_edges` state. Review and Guardian threads do not
participate in that lifecycle and are intentionally outside this
filter's scope.
## What changed
This adds an experimental `parentThreadId` filter to `thread/list`.
Parent-filtered requests return direct spawned children from persisted
state while preserving the existing response shape, explicit filters,
sorting, and timestamp-only cursor behavior. The lookup does not read
rollout transcripts or recursively return descendants.
Supersedes #25112 with the narrower `thread/list` filter approach.
## How it works
1. An experimental client passes a valid thread ID as `parentThreadId`.
2. App-server routes the list through the existing thread-store and
state-database boundaries.
3. SQLite selects threads whose IDs have a direct persisted spawn edge
from that parent.
4. Omitted provider and source filters include all values; explicit
filters keep ordinary `thread/list` semantics.
5. Grandchildren, Review threads, and Guardian threads are excluded.
## Verification
State (144 tests), rollout (69 tests), and focused app-server
thread-list (31 tests) suites passed. Scoped Clippy checks and
repository formatting also passed. Coverage includes direct spawned
children, omitted grandchildren, pagination, malformed IDs, mixed source
kinds, explicit filters, and operation without rollout files.
## Why
Next slice needed to make progress on the `remote_env_windows` test is
to support passing a Windows cwd for the remote environment and using
that environment's native shell. This lets the test run a real Windows
process instead of only recording an early path or shell mismatch.
## What
- change `TurnEnvironmentSelection.cwd` from `AbsolutePathBuf` to
`PathUri`
- convert local cwd values to URIs when constructing selections
- preserve a remote primary cwd instead of replacing it with the local
legacy fallback
- prefer the selected environment's discovered shell for unified exec,
falling back to the session shell when unavailable
- convert back to a host-native absolute path at current native-only
consumer boundaries
- reject or deny unsupported foreign cwd values at the existing
request-permissions boundary, with TODOs for its future migration
- extend the hermetic Wine test to execute Windows PowerShell in
`C:\windows` and verify successful process completion
- record the current app-server rejection against the same Wine-backed
remote Windows fixture when its cwd is supplied as a native Windows path
## Why
We have some large gaps in our thread start, resume, and pre-sampling
traces that make it hard to tell where latency is coming from.
## What Changed
- Added coarse spans around thread start/resume, turn context
construction, rollout reconstruction, skill/plugin loading, and tool
preparation.
- Added a breakdown of discoverable-tool preparation across connector
loading, plugin discovery, and local plugin details.
## Testing
- `cargo check -p codex-app-server -p codex-core -p codex-core-skills -p
codex-core-plugins`
- Built the app-server locally and exercised thread start, first turn,
follow-up turn, server restart, thread resume, and a resumed turn.
## Why
Turn construction passed resolved environments through several layers
while leaving the environment shell unresolved. As a result,
model-visible environment context could fall back to the session shell
instead of reporting the selected remote environment's shell.
Resolve environment metadata at the turn-context boundary so each turn
carries the shell that belongs to its selected environment. Keep request
validation in app-server, where invalid selections can be returned as
straightforward JSON-RPC errors without coupling core turn construction
to that policy.
## What changed
- resolve environment selections eagerly in
`new_turn_context_from_configuration`
- store the full resolved `Shell` on each `TurnEnvironment`
- simplify the now-redundant resolved-environment constructor plumbing
- keep duplicate and unknown-environment validation as a small
app-server preflight
- add a remote-environment integration test that runs a full
`test_codex` turn and verifies the model-visible environment message
reports `bash`
## Testing
- `cargo check -p codex-core --test all -p codex-app-server`
- `remote_test_env_exposes_bash_shell_to_model` on the Linux
remote-executor harness
## Why
Clients can archive and unarchive threads today, but there is no
app-server API for permanently removing a thread. Deletion also needs to
cover the full session tree: deleting a main thread should remove
spawned subagent threads and the related local metadata instead of
leaving orphaned rollout files, goals, or subagent state behind.
## What
- Adds the v2 `thread/delete` request and `thread/deleted` notification,
with the response shape kept consistent with `thread/archive`.
- Implements local hard delete for active and archived rollout files.
- Deletes the requested thread's state DB row as the commit point, then
best-effort cleans associated state including spawned descendants,
goals, spawn edges, logs, dynamic tools, and agent job assignments.
- Updates app-server API docs and generated protocol schema/TypeScript
fixtures.
## Summary
Codex Apps needs app-server as the source of truth for chat-started
background terminals instead of guessing from local process trees.
This PR adds experimental v2 APIs to list and terminate background
terminals for a loaded thread using app-server process ids, so clients
can manage background terminals without local PID discovery.
## Changes
- `thread/backgroundTerminals/list` returns paginated background
terminal records with `itemId`, app-server `processId`, `command`,
`cwd`, nullable `osPid`, nullable `cpuPercent`, and nullable `rssKb`.
- `thread/backgroundTerminals/terminate` terminates one running
background terminal by app-server `processId` and returns whether a
process was terminated.
- Background terminal list and terminate operations use unified-exec
process manager state as their source of truth.
## Why
- `ThreadSource` currently defines a closed set of core-owned values
- Product features also create threads for background or scheduled work
- Adding every product-specific value to the core enum would require
repeated `codex-rs` protocol changes
- Feature-backed values let product callers provide precise attribution
while preserving the existing core classifications
## What Changed
- Adds `ThreadSource::Feature(String)` for app-owned thread source
values
- Represents all app-server v2 thread sources as scalar strings, so a
feature source is supplied as `"automation"`
- Persists and emits the feature's plain string label, so `"automation"`
produces `thread_source="automation"` in analytics
- Keeps `user`, `subagent`, and `memory_consolidation` as explicit
core-owned values and regenerates the app-server schemas and TypeScript
bindings
## Verification
- `just write-app-server-schema`
- `cargo check --workspace`
- `just test -p codex-protocol
feature_thread_source_serializes_as_its_app_owned_label`
- `just test -p codex-app-server-protocol
thread_sources_round_trip_as_scalar_labels`
- `cargo test -p codex-analytics
thread_initialized_event_serializes_expected_shape`
- `just fmt`
## Why
CCA is moving toward a split runtime where the orchestrator may not have
a filesystem, while executors can expose preinstalled plugins and
skills. A thread therefore needs to select capabilities without asking
app-server or core to interpret executor-owned paths through the
orchestrator's filesystem.
The longer-term model is broader than executor skills:
- A plugin is a bundle of skills, MCP servers, connectors/apps, and
hooks.
- A plugin root can be local, executor-owned, or hosted by a backend.
- Components inside one plugin can use different access and execution
mechanisms. A skill may be read from a filesystem or through backend
tools; an HTTP MCP server can run without an executor; a stdio MCP
server or hook needs an execution environment.
- Core should carry generic extension initialization data. The extension
that owns a component should discover it, expose it to the model, and
invoke it through the appropriate runtime.
This PR establishes that architecture through one complete vertical:
selecting a root on an executor, discovering the skills beneath it,
exposing those skills to the model, and reading an explicitly invoked
`SKILL.md` through the same executor.
## Contract
`thread/start` gains an experimental `selectedCapabilityRoots` field:
```json
{
"selectedCapabilityRoots": [
{
"id": "deploy-plugin@1",
"location": {
"type": "environment",
"environmentId": "workspace",
"path": "/opt/codex/plugins/deploy"
}
}
]
}
```
The root is intentionally not classified as a "plugin" or "skill" in the
API. It can point at a standalone skill, a directory containing several
skills, or a plugin containing skills and other components. This PR only
teaches the skills extension how to consume it; later extensions can
resolve MCP, connector, and hook components from the same selection.
The platform-supplied `id` is stable selection identity. The location
says which runtime owns the root and gives that runtime an opaque path.
App-server does not inspect or canonicalize the path.
## What changed
### Generic thread extension initialization
App-server converts selected roots into `ExtensionDataInit`. Core
carries that generic initialization value until the final thread ID is
known, then creates thread-scoped `ExtensionData` before lifecycle
contributors run.
This keeps `Session` and core independent of the capability-selection
contract. The initialization value is consumed during construction; it
is not retained as another long-lived `Session` field.
### Executor-backed skills
The skills extension now owns an `ExecutorSkillProvider` that:
- resolves the selected environment through `EnvironmentManager`
- discovers, canonicalizes, and reads skills through that environment's
`ExecutorFileSystem`
- contributes the bounded selected-skill catalog as stable developer
context
- reads an explicitly invoked skill body through the authority that
listed it
- warns when an environment or root is unavailable
- never falls back to the orchestrator filesystem for an executor-owned
root
Skill catalog and instruction fragments have hard byte bounds, which
also bound them below the 10K-token per-item context limit. If a
selected executor skill has the same name as a legacy local skill, the
executor selection owns that invocation and the local body is not
injected a second time.
Existing local and bundled skill loading remains in place. Omitting
`selectedCapabilityRoots` therefore preserves current local-only
behavior.
## Current semantics
- Only environment-owned locations are represented in this first
contract.
- Roots are resolved by the destination extension, not by app-server or
core.
- An unavailable executor or invalid root produces a warning and no
capabilities from that root; it does not trigger a local-filesystem
fallback.
- Selection applies to a newly started active thread.
- MCP servers, connectors, and hooks beneath a selected plugin root are
not activated yet.
- Selection is not yet persisted or inherited across resume, fork, or
subagent creation. Existing local capabilities continue to behave as
they do today in those flows.
## Planned vertical follow-ups
1. **Hosted HTTP MCP:** add an extension-backed HTTP MCP source that
works without an executor, then replace the special-purpose MCP plugins
loader with that implementation.
2. **Executor MCP:** register and execute stdio MCP servers through the
environment that owns the selected plugin root.
3. **Backend skills:** add a hosted skill source whose catalog and
bodies are accessed through extension tools rather than a filesystem.
4. **Connectors and hooks:** activate those components through their
owning extensions, using the same selected-root boundary and
component-specific runtime.
5. **Durable selection:** define the desired-selection lifecycle,
persist it, and make resume, fork, and subagent inheritance explicit
rather than accidental.
6. **Local convergence:** incrementally route existing local plugin,
skill, and MCP loading through the same extension model while preserving
current local behavior.
Each follow-up remains reviewable as an end-to-end capability. The
platform selects roots, generic thread extension data carries the
selection, and the owning extension resolves and operates its component.
## Verification
Coverage added for:
- app-server end-to-end discovery and explicit invocation of a skill
inside an executor-selected plugin root
- exclusive invocation when a selected executor skill collides with a
local skill name
- executor filesystem authority for discovery, canonicalization, and
reads
- thread extension initialization before lifecycle contributors run
- stable executor catalog context, explicit invocation, context
rebuilding, hidden skills, and preserved host/remote catalog behavior
Targeted protocol, core-skills, skills-extension, core lifecycle, and
app-server executor-skill tests were run during development.
## Summary
- reuse the history-bearing `StoredThread` loaded while probing for a
running thread
- avoid rereading and reparsing the rollout when that probe finds no
active process
- reload after shutting down a loaded thread because shutdown may flush
newer rollout items
- add a regression test that verifies cold resume performs one
history-bearing store read
## Problem
`thread/resume` first reads the persisted thread with history while
checking whether the thread is
already running. When no running process exists, cold resume currently
falls through to
`resume_thread_from_rollout`, which reads and parses the same history
again.
That duplicate work grows with rollout size and remains on the
synchronous resume path even when
the caller requests `excludeTurns`.
## Background
The duplicate read was introduced by #24528, which fixed resume
overrides for idle cached
threads. To support resumes specified by rollout path,
`resume_running_thread` began loading the
stored thread with history so it could resolve the canonical thread ID
and determine whether a
cached `CodexThread` was already loaded.
That history is needed when the loaded-thread path handles the request.
On a cold miss, however,
the function's boolean result could only report that no loaded thread
handled the request. It
discarded the history-bearing `StoredThread`, and the normal cold-resume
path immediately loaded
and parsed the same rollout again.
This change preserves the idle cached-thread behavior from #24528 while
allowing the cold-resume
path to reuse the probe result.
## Performance
I benchmarked real retained rollouts using isolated `CODEX_HOME`
directories, explicit rollout
paths, debug builds of the commit and its exact parent, and alternating
parent/patch order. The
table below uses `thread/resume` with `excludeTurns: true`; response
payload sizes were identical.
| Rollout size | Records | Parent median | Patch median | Median paired
saving |
| ---: | ---: | ---: | ---: | ---: |
| 6 MB | 3,574 | 541 ms | 441 ms | 132 ms |
| 30 MB | 15,220 | 1.505 s | 1.041 s | 701 ms |
| 60 MB | 31,453 | 2.644 s | 1.742 s | 970 ms |
| 149 MB | 100,874 | 10.506 s | 7.156 s | 3.350 s |
| 559 MB | 259,734 | 27.759 s | 16.725 s | 9.836 s |
The absolute saving increases with thread size, as expected when
removing one complete JSONL
history read and parse. Total resume time is also content-dependent, so
the relationship is not
perfectly linear.
I also tested full-history resume with `excludeTurns: false`. The
response payload was
byte-identical between variants, and the same size-dependent improvement
remained visible:
| Rollout size | Parent median | Patch median | Median paired saving |
| ---: | ---: | ---: | ---: |
| 6 MB | 1.052 s | 904 ms | 270 ms |
| 30 MB | 2.667 s | 1.762 s | 924 ms |
| 60 MB | 8.464 s | 6.272 s | 3.680 s |
| 149 MB | 26.719 s | 12.118 s | 14.601 s |
| 559 MB | 40.359 s | 25.475 s | 16.590 s |
## Validation
- `just test -p codex-app-server
cold_thread_resume_reuses_non_local_history_probe`
- `just fix -p codex-app-server -p codex-thread-store`
- `just fmt`
## Why
Thread cwd and environment selections are a single logical setting in
core: updating one without the other can silently desynchronize the
next-turn execution context. This change makes that relationship
explicit in the internal thread settings flow while preserving the
existing app-server public API shape.
## What changed
- Moved the cwd/environment pair through internal
`ThreadSettingsOverrides.environment_settings` instead of a top-level
internal `cwd` field.
- Kept `thread/settings/update` public params unchanged, with app-server
translating top-level `cwd` into the paired internal settings shape.
- Moved `Op::UserInput` environment overrides into thread settings so
user turns and settings updates use the same core path.
- Updated core, app-server, MCP, memories, sample, and test callsites to
construct the paired settings shape.
## Verification
- `git diff --check`
- Local test run starting after PR creation.
Stacked on #26532.
## Why
#26532 moves cwd normalization to the app-server/core boundary.
`runtimeWorkspaceRoots` still accepted raw paths in v2 requests and in
`ConfigOverrides`, which left core responsible for interpreting those
roots later. This makes runtime workspace roots follow the same
absolute-path boundary as cwd.
## What
- Change v2 `runtimeWorkspaceRoots` request fields for `thread/start`,
`thread/resume`, `thread/fork`, and `turn/start` to `AbsolutePathBuf`.
- Deduplicate already-absolute runtime roots in app-server handlers and
pass them through `ConfigOverrides.workspace_roots` as
`AbsolutePathBuf`.
- Update TUI and exec client request builders to pass absolute runtime
roots directly.
- Update app-server docs, schema fixtures, and focused tests for
absolute runtime roots.
## Testing
- `just test -p codex-app-server-protocol`
- `just test -p codex-app-server runtime_workspace_roots`
- `just test -p codex-core
session_permission_profile_rebinds_runtime_workspace_roots`
- `just test -p codex-tui app_server_session`
- `just test -p codex-exec`
