## What changed
- Add effective workspace roots to `EnvironmentConfig` and use them when
materializing permission profiles and filesystem context.
- Preserve selection roots for thread-owned configurations while allowing a
ready environment attachment to supply its resolved roots.
- Propagate resolved roots to child environments and validate both command and
`apply_patch` writes in owner-provided secondary workspaces.
GitOrigin-RevId: 1832c168ce1fc37fa67efc2a472998ab4f448c70
## What changed
Rename the `UserInstructions` type to `Instructions` across the extension API,
its core API re-export, and all consumers. This keeps loading behavior and the
`LoadedUserInstructions` provider interface unchanged.
GitOrigin-RevId: 1ac236b34c31718e7aa38ff5eae5e9b179aeedd8
## What changed
- Add the experimental `turn/start.cyberAccessProgram` option with `standard`,
`daybreakBlue`, and `daybreakRed` values.
- Forward the selection as `access_programs.cyber` on Responses, WebSocket,
and remote-compaction requests made with ChatGPT authentication, while
omitting it for API-key and custom-provider requests.
- Preserve the per-turn selection across recovery, compaction, and child-agent
turns without making it a persistent thread setting.
## Testing
- Cover app-server forwarding, authentication boundaries, WebSocket reuse,
turn recovery, compaction, and child-agent inheritance.
GitOrigin-RevId: d2eb468f365b2214c5099bc21741cf30f8bd2eb5
## Why
Thread settings can change while a turn is running, and delegated review or
compaction steps can select a different model. Each request needs a consistent
set of settings resolved against the model that will execute it.
## What changed
- Capture immutable resolved settings for each model step, including model
metadata, reasoning options, service tier, approvals, and personality.
- Keep in-flight steps on their captured settings while applying thread updates
to subsequent work.
- Resolve inherited reasoning summaries and filter service tiers against the
selected model and feature configuration for review and compaction steps.
## Testing
Added coverage for settings updates during paused turns, model changes,
previous-model compaction, review-model defaults, and service-tier filtering.
GitOrigin-RevId: fca4b3b305379f1bf26a5cac75ee0dd1747ac1f6
## Why
Post-commit work can overlap with another settings write. Reading the session
again afterward could make a settings operation report or use the later state
instead of the state that it committed.
## What changed
- Return the committed configuration and `ThreadSettingsSnapshot` from session
settings updates.
- Use that commit result when creating a turn and emitting
`ThreadSettingsApplied`, while retaining current-state snapshots for
synthesized fork history.
- Route turn-start updates through the shared settings update path.
## Testing
Add coverage for standalone and turn-start updates that pause after committing,
restore different settings concurrently, and verify that each operation keeps
its original configuration and notification snapshot.
GitOrigin-RevId: cee5be9536d2840170893e6eb0c64cd039fb0a96
## Why
Guardian sessions can run alongside another Windows sandbox launch and should not reconcile the persistent proxy settings established by that launch.
## What changed
- Start internal Guardian sessions with `WindowsSandboxProxySettingsMode::Preserve`.
- Continue using `Reconcile` for other sessions.
## Testing
Added a thread manager test that verifies a parent session reconciles proxy settings while its internal Guardian session preserves them.
GitOrigin-RevId: c6a31637ecdf828548cfd7153da7e9405abe34fa
## What changed
- Add Windows sandbox mode, private-desktop behavior, and legacy Landlock selection to each `EnvironmentConfig`.
- Centralize sandbox context construction on `TurnEnvironment`, preserving environment-owned permissions, paths, and backend settings while applying additional permission grants.
- Use the environment-derived context for project instructions, capability discovery, file uploads, and filesystem-oriented tools.
## Testing
- Verify capability discovery uses the selected environment's permission profile and sandbox backends when they differ from the thread defaults.
GitOrigin-RevId: 7ae2fed90c8ada950f2e8431e571e9b2c793c291
## Why
Internal Guardian reviews must remain independent of parent-session customization while still honoring managed execution and environment restrictions.
## What changed
- Apply the restricted Guardian session path to both internal and subagent review sources.
- Start internal reviews without inherited user instructions, extensions, MCP servers, or multi-agent behavior.
- Preserve managed execution policy and selected environment constraints while exposing only the allowed review tools. Honor shell feature restrictions across every selected environment and retain code mode when enabled.
## Testing
- Cover internal review isolation from parent state and managed instructions.
- Cover optional tool filtering, managed shell restrictions, code mode, and secondary environment profiles.
GitOrigin-RevId: edbf7d8a6fe3ee8213a1c75bc8ec331a1cf49006
## What changed
- Preserve each contextual fragment's `ContentItemKind` when converting it to a response message.
- Classify user text, image, and audio content as `user.text`, `user.image`, and `user.audio` in their original order.
- Give additional context key-specific `additional_content.<key>` kinds and retain annotations on generated messages such as image resize notices and interrupted-turn markers.
## Testing
- Expand request-level coverage to verify content-kind annotations across mixed-modality turns, additional context, reminders, budgets, skills, model switching, subagents, and image resizing.
GitOrigin-RevId: 671e4545f39b335525c60d2a5df4608e8068cafc
## What changed
- Add an extension API for spawning host-owned internal sessions and a
`ThreadReadyInput` lifecycle callback that runs after thread registration.
- Add Guardian reviewer session scaffolding that records the parent thread and
effective model, plus the under-development `guardian_ext` feature flag.
- Start internal sessions with fresh history while preserving parent lineage,
shared session controls, and internal-thread visibility rules.
- Scope internal-session prompt cache keys to their source and parent thread,
and expose `guardian` as an internal session source.
## Testing
- Cover internal-session spawning, parent metadata, history isolation, prompt
cache keys, and extension spawner argument forwarding.
GitOrigin-RevId: 682dae80397d62bb36247796b447042e760ca364
## What changed
- Add environment-provided MCP restrictions for configured and plugin-provided servers.
- Disable attachment-scoped servers while their environment configuration is pending, failed, or unselected, while preserving selected-plugin access and the controller-owned Apps server.
- Apply the resolved policy to runtime startup, model tool exposure, telemetry, OAuth flows, and skill dependency installation.
## Testing
- Cover policy filtering for configured and plugin servers, environment state transitions, Apps ownership, and managed OAuth rejection.
GitOrigin-RevId: 7ca5d4dda14068e758497f88835d5cba685e159e
## What changed
- Add an optional `delivery` field to agent message events and app-server
`agentMessage` items, with `"async"` identifying a user-visible message sent
without ending the current turn.
- Preserve the marker through legacy event conversion, thread history
materialization, replay, and generated JSON and TypeScript schemas.
- Require delivery of async agent message completion notifications on the
in-process app-server transport.
## Testing
- Cover preservation of async delivery metadata in thread history.
- Cover delivery-required classification for async agent messages.
GitOrigin-RevId: f92ba25de1293ee271404badfdf0d117d6530329
## Why
Callers need to associate host-owned state with a thread before Core starts it.
## What changed
- Add `ThreadManager::reserve_thread_id` and allow new threads to start with the reserved ID. Reject reserved IDs when resuming an existing thread.
- Let thread stores stage metadata for a reserved ID. The local store merges staged values into the first successful metadata update and then removes them.
- Clear staged metadata when an unmaterialized thread shuts down or is discarded, and require the state database for staging.
## Testing
- Cover reserved ID generation and resume validation.
- Cover metadata persistence, merging, rollout-compatible updates, cleanup, and invalid staging requests.
GitOrigin-RevId: 3f9bc48f0f7764011cc90ea01349e497dda0a9e3
## What changed
- Add `EnvironmentConfigState` to `TurnEnvironmentSelection` so each environment attachment can inherit thread configuration or carry ready configuration for its login-shell policy and selected capability roots.
- Apply ready configuration during thread creation and thread-settings updates while reusing the existing environment connection.
- Validate selection configuration before applying settings, rejecting unsupported pending state and invalid capability roots.
## Testing
- Cover attachment-scoped capability roots, ready configuration at thread startup and turn updates, and rejection of invalid selections without changing existing settings.
GitOrigin-RevId: 86cf8f2148fdaa746ea0dd12890ab7b1577d7587
## Why
Thread stores may filter a metadata patch to a no-op. Requiring every successful
update to return a `StoredThread` forces those implementations to materialize a
thread even when the caller does not need one.
## What changed
- Let `ThreadStore::update_thread_metadata` return `None` after a successful
update that did not materialize a thread.
- Preserve the materialized-thread contract of `LiveThread` and `ThreadManager`
metadata updates by reading the thread when the store returns `None`.
- Keep completion-only metadata updates from issuing that fallback read.
## Testing
Cover materialized in-memory updates and verify that fallback reads occur only
for callers that require the updated thread.
GitOrigin-RevId: 3059efc9d5b69e0b46e35fb5b5aa9638086654f2
## What changed
- Wrap response items with optional harness-owned metadata while keeping the persisted response payload shape backward compatible.
- Store compacted-history metadata in an aligned sidecar and reject malformed sidecars.
- Carry metadata through history normalization, compaction, resume, fork, truncation, migration, and rollout recording without sending it to model providers.
## Testing
- Cover legacy rollout compatibility, metadata serialization and validation, compaction retention, and resume/fork reconstruction.
GitOrigin-RevId: 17a6127c9048ff984cb4df4d97c0751a38c29f5f
## What changed
- Add `codex-history` for model-history and persisted-rollout domain types, including `RolloutItem`, `RolloutLine`, `CompactedItem`, and initial/resumed history state.
- Re-export the persisted types from `codex-rollout` and update consumers to use the new crate boundary instead of `codex-protocol`.
- Preserve existing rollout serialization, including legacy numeric compacted-window IDs.
## Testing
- Add `codex-history` tests for rollout JSON round trips, compacted-history compatibility, persisted history modes, and multi-agent version selection.
GitOrigin-RevId: 944daa9297ddd231d3aebbdcb05fff4adf8b4e1b
## What changed
- Add a `codex-diagnostics` crate that snapshots the process ID, available
resident-memory measurements, and registered process-wide gauges.
- Provide guards that update gauges for the lifetime of measured objects.
- Track live `CodexThread` instances with the `core.threads.live` gauge.
## Testing
- Add unit coverage for gauge registration, guard lifetimes, process memory
snapshots, and live-thread reporting.
GitOrigin-RevId: 3236b086bd4ebe31ed4768ab87a5fa288b0891b0
## What changed
- Add `ThreadManager::with_thread_id_generator` to configure ID allocation for new root, child, and forked threads.
- Keep the standard UUIDv7 generator as the default and preserve stored IDs when resuming threads.
- Add `ThreadId::from_u128` for constructing identifiers from UUID-compatible values.
## Testing
- Cover default allocation, custom IDs across roots, child agents, and forks, and ID preservation on resume.
GitOrigin-RevId: 6c38c862e30a50bad944a994bcbccf7d1e7ada24
## What changed
- Add `session_source()` to `McpServerContributionContext` for thread-scoped MCP resolution.
- Propagate each thread's `SessionSource` through initial setup, per-step resolution, and runtime refreshes.
## Testing
- Verify global contexts omit the source while thread-scoped contexts retain it.
- Verify MCP contributors observe distinct sources for a root thread and its spawned subagent.
GitOrigin-RevId: 23da1509858e023fbd9e2d179034ddc83553f17b
## Why
App-server clients need to advertise structured MCP extension settings, including supported MCP App UI MIME types, rather than only opting into OpenAI form elicitation with a boolean.
## What changed
- Add an `extensions` map to initialize capabilities and preserve `mcpServerOpenaiFormElicitation` as a legacy alias for `openai/form`.
- Capture the declared extension profile when a thread is started, resumed, or forked, propagate it to subagents, and advertise it to downstream MCP servers during initialization.
- Keep the profile stable for the lifetime of the loaded session instead of changing it on later turns or direct tool calls.
## Testing
- Cover extension conversion, downstream MCP initialization, session isolation, legacy form support, and subagent inheritance.
GitOrigin-RevId: fbcedbb74ce788e574b0f884a4c45c4cedb9de54
## What changed
- Move the V8 implementation into a dedicated `codex-code-mode-runtime` crate used by `codex-code-mode-host`, removing the embedded runtime fallback from the Codex process.
- Resolve the host executable from the active installation layout and check its availability before selecting tools.
- Fall back to direct tools with a one-time warning when optional code mode is unavailable. Keep `code_mode_only` and `disable_in_process_fallback` configurations fail-closed.
## Testing
- Cover host discovery for standalone and package layouts, including missing hosts and symlinks.
- Verify direct-tool fallback, one-time warnings, and fail-closed code-mode-only behavior.
GitOrigin-RevId: 5aa3c6f1db148b2231fc24089a2ee0e2b00dbddb
## What changed
- Preserve `encrypted_function_args` on function calls so an empty list can mark plaintext collaboration arguments across request replay.
- Deliver `spawn_agent`, `send_message`, and `followup_task` payloads as structured plaintext agent messages when that marker is present; retain encrypted delivery otherwise.
- Redact plaintext collaboration arguments from tool and communication logs, and omit the metadata when sending requests to non-OpenAI providers.
## Testing
- Cover serialization of empty encrypted-argument metadata and plaintext versus encrypted subagent message delivery.
- Verify plaintext tool arguments are redacted and provider-specific metadata is removed from non-OpenAI requests.
GitOrigin-RevId: 64db98ff0b61a3af2f04ed609292363f2e2362a8
## Why
MCP configuration can change while a thread is still starting, before it appears in the thread manager's loaded-thread list. In that window, invalidation could miss the new thread and leave it with a stale MCP runtime.
## What changed
- Centralize MCP runtime invalidation in `ThreadManager` so it refreshes loaded threads and marks in-progress thread startups for refresh after publication.
- Use the centralized invalidation path for account and plugin changes.
- Invalidate MCP runtimes after successful server and plugin OAuth logins.
## Testing
- Add a regression test that pauses thread startup, invalidates MCP runtimes, and verifies that the newly published thread refreshes its MCP projection.
GitOrigin-RevId: 8944f5a21816a1405e038a0d4c08b66362ea9368
## What changed
- Add `--code-mode-host ws://...` and `wss://...` support to `codex app-server`, gated by the `code_mode_host` feature. When omitted, app-server continues to start a local host.
- Share one remote WebSocket connection across the process's threads, using the configured HTTP client's proxy and TLS policy and preserving the existing framed host protocol.
- Reject invalid host URLs, bound WebSocket frame sizes, close connections cleanly, and return an error when a connection exceeds 1,024 pending delegate calls without disconnecting it.
## Testing
- Cover CLI validation, WebSocket protocol execution and shutdown, connection sharing across app-server threads, and delegate-call capacity recovery.
GitOrigin-RevId: 715e82d4d9db1e7e2f91b754a777dcab504e2ae4
## What changed
- Add `StartThreadOptions::new` to provide the standard configuration for a new thread.
- Make `ThreadManager::start_thread` the single thread-start entry point and migrate callers from the previous convenience methods.
- Derive default environment selections when `environments` is `None`, while preserving explicit selections, including an empty list.
GitOrigin-RevId: 8977dc11aed54c5e1215a81eaed2b2cf5fc6087a
## What changed
- Assign IDs to client-created response items in every session, including streamed items, forked history, compaction results, and non-OpenAI provider requests.
- Preserve server-provided IDs and stable generated IDs across persisted and resumed conversations while continuing to omit unprefixed server IDs from outbound requests.
- Retire `features.item_ids` as a configurable feature. Existing configuration and CLI toggles remain accepted as compatibility no-ops.
## Testing
- Cover default ID assignment, persistence and resume behavior, remote compaction, provider requests, WebSocket requests, and removed-feature compatibility.
GitOrigin-RevId: 7a09e2d07d2606c2ef1e8e2283d36cb555557eae
## Why
Selected capability roots can contribute plugins, MCP servers, connectors, and
skills. Discovering each contribution separately requires repeated access to the
executor filesystem.
## What changed
- Add the `capabilityRoots/discoverV1` exec-server RPC to scan selected roots and
materialize recognized plugin manifests, configuration files, skill
instructions, and skill metadata in one bounded request.
- Add the opt-in `executor_capability_discovery` feature, with a thread-scoped
cache and per-step snapshot shared by MCP and skill discovery.
- Parse MCP, connector, and skill contributions from the materialized snapshot,
including serving cached skill instructions without another filesystem read.
## Testing
- Cover discovery limits, manifest precedence, root-local failures, cache reuse,
plugin contributions, and parity with the existing environment skill loader.
GitOrigin-RevId: f98fd2321cafb58c596db02da1f83c09d8eb375d
## Why
Standalone web search and image requests need to preserve the trusted,
thread-scoped originator used for billing attribution.
## What changed
- Seed extension data with the resolved thread originator and recognize
`codex_work_cca` and `chatgpt_cca` service names as originators.
- Forward non-default originators from the web search and image generation
extensions with the shared originator-header helper.
## Testing
- Cover originator resolution, header validation, and forwarding for web
search, image generation, and image editing.
GitOrigin-RevId: 165dace8e4d24e4bd92f234bff5ec77a21a7ff6e
## Why
With deferred execution enabled, rebuilding a step context from the latest
thread environment snapshot could apply a settings update to a turn that was
already in progress.
## What changed
- Preserve each turn's captured environment selections when creating later
step contexts.
- Refresh only the readiness of environments that were already starting, while
retaining their original selection order.
- Apply updated environment selections to the next turn.
## Testing
Add coverage for changing the selected workspace while a turn is paused,
verifying that the active turn keeps its original working directory and the
next turn uses the new one.
GitOrigin-RevId: c6f4388c843384ef045b7abdbc303dcfca11d230
## What changed
- Let deferred environments provide selected capability roots with their ready signal.
- Validate that those roots have unique, non-empty IDs, belong to the registering environment, and stay within the root limit.
- Include roots from ready turn environments when resolving MCP contributions, and refresh the MCP runtime when the selected root set changes.
- Expose the exact ready root set to MCP contributors so executor plugins become available with their environment.
## Testing
- Cover ready-root propagation, validation failures, replacement isolation, reconnection, and MCP plugin availability refresh.
GitOrigin-RevId: ec3498aab1164824025094e96a9b1063b7b731ad
## What changed
- Replace the combined `Codex` wrapper with an `Arc<Session>` and a dedicated
`SessionIo` handle for submissions, events, status, and loop termination.
- Make `Session::spawn` return the session and I/O handle separately, and have
`CodexThread` own both.
- Update thread management, delegated sessions, guardian reviews, and agent
control to use the appropriate session or I/O interface.
GitOrigin-RevId: 8523bad7e7366e2969fd0cc3849b4247b141427a
## What changed
- Accept a caller-provided `CodexAppsToolsCache` when constructing a `ThreadManager` and pass it through to the MCP manager.
- Add `ConnectorRuntimeManager::new_without_cache()` for an in-memory runtime that neither loads nor persists connector state on disk.
- Re-export `CodexAppsToolsCache` from `codex-core` and `codex-core-api` for embedders.
## Testing
- Verify that a cache-disabled connector runtime ignores existing disk state and publishes live tools without creating cache files.
GitOrigin-RevId: f52f4f27c425a8d84ad0d0987b30a6fc3c14d702
## 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
## Why
Embedding callers need to control whether model catalogs are persisted to disk.
## What changed
- Accept a shared models manager when constructing `ThreadManager` instead of always creating a cached manager internally.
- Add provider APIs for creating uncached model managers. OpenAI-compatible providers fetch on each `OnlineIfUncached` refresh without reading or writing `models_cache.json`.
- Keep existing app server, MCP server, sample, and test callers on the standard cached manager.
## Testing
- Verify an uncached manager fetches on every refresh.
- Verify an injected uncached manager controls thread refresh behavior and does not create `models_cache.json`.
GitOrigin-RevId: 8bb646054ecec4ccb865b2bf56249384916ea9db
## What changed
- Add a `ResponseItemId` type that generates item-specific prefixes with UUIDv7 suffixes and use it across response items.
- Keep deserialization permissive for legacy histories, but omit empty or unprefixed item IDs from HTTP and WebSocket requests.
- Export the new type in the generated TypeScript protocol schema.
## Testing
- Cover prefixed ID generation, legacy deserialization, prefix recognition, and outbound request filtering.
GitOrigin-RevId: 0209fe430c826d0ae88bc4648652c4ebf390c4a4
## What changed
- Add an optional `started_at` Unix timestamp to `TurnCompleteEvent` and
`TurnAbortedEvent`.
- Populate the timestamp from turn timing state when a turn completes or is
aborted.
- Preserve the timestamp when synthesizing interrupted fork history and when
importing external sessions.
## Testing
- Verify that interrupting a turn emits a `TurnAbortedEvent` with a start
timestamp.
GitOrigin-RevId: 75b3911b95c060e5fc1843a5e293d8fe47377186
## Summary
- Forward Codexs canonical `originator` header on ChatGPT-hosted Apps
and plugin-runtime MCP requests.
- Preserve the configured `X-OpenAI-Product-Sku` header.
- Cover originator-only and originator-plus-SKU configurations.
## Why
Sites project creation is logged downstream of Apps MCP. Production
validation found `CODEX_UNKNOWN_DEFAULT` project-created threads that
matched `codex_surface=desktop_app` and `originator=Codex Desktop` in
`fact_codex_cli`
([query](https://kepler.gateway.data-1.internal.api.openai.org/permalink/H_mVoVPqLQ0)).
The hosted Apps MCP configuration forwarded the product SKU but not
Codexs canonical originator, so codex-backend could not derive
`CODEX_DESKTOP_APP` for those tool calls.
## Validation
- `just fmt`
- `CARGO_HOME=/private/tmp/codex-cargo-home
CARGO_TARGET_DIR=/private/tmp/codex-target just test -p codex-mcp` (106
passed)
- `CARGO_HOME=/private/tmp/codex-cargo-home
CARGO_TARGET_DIR=/private/tmp/codex-target just fix -p codex-mcp`
## Why
Generic plugin guidance is currently emitted only with initial context
from host plugin state. An executor-selected plugin can become available
later in the same turn, making its skills and tools usable without ever
telling the model how plugin capabilities should be used.
## What
- project every ready selected plugin package, including skill-only
plugins
- carry plugin availability with the exact MCP runtime projection while
preserving MCP manager reuse when servers and connectors are unchanged
- move generic plugin guidance from the static initial-context path into
persisted World State
- recognize legacy and retained plugin fragments so resume and
compaction do not duplicate guidance
## Testing
- `just test -p codex-mcp-extension`
- `just test -p codex-core plugins_instructions`
- `just test -p codex-core
plugin_availability_change_reuses_the_mcp_manager`
- `just test -p codex-app-server --test all selected_capabilit`
## 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.
## Summary
- add the `code_mode_host` feature flag and select
`ProcessOwnedCodeModeSessionProvider` in `CodeModeService` when enabled
- initialize code-mode sessions lazily so a missing host reports a tool
error without failing thread startup
- resolve `codex-code-mode-host` beside the running Codex binary by
default while preserving `CODEX_CODE_MODE_HOST_PATH` as an override
- add unit and end-to-end coverage for host resolution and graceful
missing-host behavior
## Why
This wires the process-owned session client from #30112 into the core
service behind an opt-in rollout gate. Packaged Codex installations can
place the helper in the same `bin` directory as the main executable
without relying on `PATH`, while development and custom installations
can continue to override the helper path.
## Stack
- Depends on #30112
- Base branch: `cconger/process-owned-session-runtime-4-client`
## Validation
Build `codex` and `codex-code-mode-host`
`CODEX_CODE_MODE_HOST_PATH="$PWD/target/debug/codex-code-mode-host"
./target/debug/codex --enable code_mode_host`
## 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.
## Summary
- recognize `codex_work_web` and `codex_work_mobile` as supported
`thread/start.serviceName` values
- use the recognized value as the thread-scoped originator, with the
same persistence and request propagation added for `codex_work_desktop`
- cover precedence over persisted and inherited originators
This is the Codex consumer for the service names introduced by
[openai/openai#1073178](https://github.com/openai/openai/pull/1073178).
## Rollout / Compatibility
The producer is ChatGPT's app-server integration in
openai/openai#1073178. This PR is the Codex app-server consumer that
converts those service names into the outgoing per-thread `originator`.
Until this change is deployed, the new service names are ignored and
Codex continues using its fallback originator. Deploy this mapper and
the matching codex-backend compatibility change in
[openai/openai#1073594](https://github.com/openai/openai/pull/1073594)
while the existing Flora egress overwrite remains in place. Remove that
overwrite in
[openai/openai#1073197](https://github.com/openai/openai/pull/1073197)
only after both consumers are deployed.
## Validation
- `just test -p codex-core
effective_originator_prefers_thread_scoped_sources_before_env_originator`
- `just fix -p codex-core`
- `just fmt`
## 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
`selectedCapabilityRoots` is durable thread intent: “use this capability
root from environment `worker`.”
The important product assumption is:
> One environment ID always names the same logical executor and stable
contents.
`worker` does not silently change from executor A to an unrelated
executor B. The process-local connection handle for `worker` can still
be replaced while Codex is running, though, for example when
`environment/add` registers a fresh handle for the same logical
environment.
The thread should persist only the stable selection. Each model step
should pair that selection with the exact ready handle captured for that
step.
## The boundary
```text
persisted thread intent
plugin@1 -> environment "worker"
|
| capture the current step
v
model-step view
unavailable, or
plugin@1 + worker's exact captured ready handle
```
The environment ID is the stable identity and cache key. The
`Arc<Environment>` is only a process-local handle retained so consumers
of one model step use the same captured environment. It is never
persisted and it does not imply different environment contents.
## What changes
### Persist the stable selection
Selected roots are written into `SessionMeta` and restored with the
thread. Forked subagents inherit the same selections, including
bounded-history forks.
Only stable data is persisted: root ID, environment ID, and root path.
### Capture readiness together with the exact handle
The environment snapshot records:
```rust
environment_id -> Some(Arc<Environment>) // ready in this step
environment_id -> None // still starting in this step
```
This prevents readiness and execution from coming from different
registry snapshots.
For example:
```text
step snapshot: worker -> handle A, ready
environment/add: worker -> fresh handle B for the same logical environment
current step: plugin@1 still uses captured handle A
```
Without carrying handle A in the snapshot, the resolver could combine “A
was ready” with handle B and treat B as ready before it had finished
starting.
This does not change cache invalidation. Stable capability metadata
remains identified by environment ID and capability root. Replacing a
process-local handle under the same stable environment ID does not
invalidate or rediscover that metadata.
### Resolve availability per model step
- A ready captured environment produces resolved roots using its
captured handle.
- A starting, missing, or failed environment is omitted from that step.
- A selected lazy environment that is outside the turn's captured
environment set is asked to start, and a later step can observe it as
ready.
- No capability files are scanned here.
Transient transport disconnects remain the remote client's reconnect
concern. This PR models initial attachment/readiness; it does not add
live socket-connectivity state.
## Example
```text
thread selection: plugin@1 -> environment "worker"
step 1: worker is starting -> plugin@1 unavailable
step 2: worker is ready -> plugin@1 resolves through worker's captured handle
step 3: fresh local handle -> current step remains pinned; a later step captures its own view
```
Temporary unavailability does not discard the durable selection. Later
PRs can retain stable metadata caches while projecting only currently
available capabilities into model-visible World State.
## Compatibility
The app-server request shape does not change. Older rollouts without
`selected_capability_roots` deserialize to an empty list.
## Stack
1. **This PR:** persist stable selected roots and resolve them through
an exact model-step handle.
2. #29960: cache stable skill metadata and project available skills into
World State.
3. #29946: cache stable plugin declarations and manage the separate live
MCP runtime.
## Why
With deferred executors, a turn can begin before a remote environment
attaches. AGENTS.md discovery previously ran only during session setup,
so instructions from a later environment never reached the model or the
session instruction sources.
WorldState persistence has now landed, so this uses the durable
model-visible baseline directly instead of carrying a temporary
resume/fork compatibility path.
## What
- Add an `AgentsMdManager` in `SessionServices` to own host
instructions, loaded state, and refresh caching.
- When `DeferredExecutor` is enabled, refresh AGENTS.md when attached
environment selections change and freeze the result in the corresponding
`StepContext`.
- Represent AGENTS.md as a persisted WorldState section for every
session, with bounded initial, replacement, and removal updates.
- Remove duplicate AGENTS.md state and rendering from
`SessionConfiguration` and `TurnContext`.
- Build initial context, per-request updates, and compaction context
from the same step-scoped value.
- On resume and fork, compare current instructions with the restored
WorldState baseline and inject a replacement exactly once when they
differ.
Builds on #29833, #29835, and #29837.
## Tests
- Covers a remote environment becoming ready mid-turn, with AGENTS.md
appearing on the next request exactly once and updating canonical
instruction sources.
- Covers full, unchanged, replaced, and removed AGENTS.md WorldState
rendering.
- Covers changed instructions across cold resume and fork without
duplicate reinjection.
- Covers remote-v2 compaction retaining creation-time instructions in
the live session and cold resume appending one replacement when the
source changed.
- Ran focused `codex-core` AGENTS.md, WorldState, and context-update
test suites.
## 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
Work(TPP) threads can be launched from the Desktop app, but if they all
keep the Desktop app's default originator then downstream attribution
cannot distinguish local Work launches from cloud-backed Work launches.
`thread/start.serviceName` already carries that launch signal, while
`SessionMeta.originator` is the durable thread-level value that survives
resume and fork.
This change converts the Desktop Work service names into an effective
originator at thread creation time, persists that originator with the
thread, and keeps using it for later model requests and memory writes.
## What changed
- Map `CODEX_WORK_LOCAL` and `CODEX_WORK_CLOUD` service names to
per-thread originators, while preserving
`CODEX_INTERNAL_ORIGINATOR_OVERRIDE` as the highest-precedence override.
- Persist the effective originator in `SessionMeta.originator`, read it
back on resume/fork, and inherit the parent originator for subagent
spawns when there is no persisted session metadata.
- Handle truncated `SpawnAgentForkMode::LastNTurns` forks by falling
back to the live parent originator when the forked history no longer
includes `SessionMeta`.
- Thread the per-thread originator through Responses headers,
websocket/compaction request paths, thread-store creation, rollout
metadata, and memory stage-one telemetry.
## Verification
- `just test -p codex-core
agent::control::tests::spawn_thread_subagent_inherits_parent_originator_without_fork
agent::control::tests::spawn_thread_subagent_fork_last_n_turns_inherits_parent_originator_without_session_meta
thread_manager::tests::originator_override_precedes_service_name_remapping`
- `just test -p codex-core
agent::control::tests::resume_thread_subagent_restores_stored_metadata_and_effective_multi_agent_mode`
- `just test -p codex-memories-write`
- `just fix -p codex-core -p codex-memories-write`
- `git diff --check`