## 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
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
## Why
Agent roles can override the model or reasoning effort after the initial
`spawn_agent` configuration is validated, leaving an unsupported combination
unchecked.
## What changed
- Validate the final reasoning effort against model metadata whenever a role
changes the spawned agent's model settings.
- Preserve independently configured subagent defaults when a role does not
override them.
- Apply the same role validation in both multi-agent spawn implementations.
## Testing
Added coverage for independent model and reasoning defaults, instruction-only
roles, and rejection of a reasoning effort unsupported by a role-selected
model.
GitOrigin-RevId: 1885314e9380f778603f067fc04a6225ee963428
## What changed
- Allow parallel `write_stdin` tool calls to interact with independent terminal sessions.
- Serialize reads and writes within each session so its output buffer and process lifecycle remain consistent.
- Prevent active sessions from being pruned while a `write_stdin` interaction is in progress.
## Testing
- Added unified exec and code mode coverage that uses two terminal sessions concurrently and verifies output from both.
GitOrigin-RevId: 618f5503f4c4670421f680c0f0c27414bc6b2ddd
## What changed
- Tell the model to call `wait_for_environment` only when a task needs the selected environment's files, commands, or installed capabilities.
- Document that waiting can take several minutes and blocks other tool calls, and direct the model to continue if startup fails.
- Require the exact `starting` environment ID shown in `<environment_context>`.
GitOrigin-RevId: 6b434b835d379318879d5499c365c70598673afd
## What changed
- Apply `agents.default_subagent_model` and
`agents.default_subagent_reasoning_effort` when a spawn request does not
provide explicit values, including agent job workers.
- Allow full-history forks to use configured defaults or explicit model and
reasoning-effort overrides while retaining the parent conversation context.
- Preserve the selected model and reasoning effort when an agent role does not
override them.
## Testing
- Cover configured defaults, explicit override precedence, full-history forks,
role application, and agent job workers.
GitOrigin-RevId: b1efa8c9abeee82355088fceef57560433144595
## Why
The `agent_type` argument is only useful when agent roles are configured. Avoid
advertising an inapplicable override in the model-visible `spawn_agent` schema.
## What changed
- Include `agent_type` in the V1 and V2 spawn tools only when configured roles
are available.
- Clarify that `agent_type` is an explicit override and document its interaction
with context forking.
- Remove the unused `agents.support_agent_type` configuration field.
## Testing
- Add coverage for hiding `agent_type` without roles and exposing it when a role
is configured.
GitOrigin-RevId: 32e0f123b15f317e9cdb71774029375bc073d9ad
## What changed
- Add `agents.enabled` as a user override for multi-agent tools while keeping an enabled `features.multi_agent_v2` authoritative.
- Rename the shared spawned-thread limit to `agents.max_concurrent_threads_per_session`, retain `agents.max_threads` as an alias, and apply the setting to both multi-agent backends.
- Add reserved subagent model, reasoning effort, and agent-type settings to the config surface and persist all resolved agent settings in config locks.
- Show the resolved `[agents]` values in TUI debug-config output.
## Testing
- Cover config loading, legacy alias normalization across merged layers, backend-selection precedence, V2 concurrency, and debug output.
GitOrigin-RevId: 2957c954a2e1aef51592768dbbccd56c4bf8f118
## What changed
- Remove `template_id` from MCP tool call items and lifecycle events.
- Remove `templateId` from app-server `McpToolCallAppContext` responses and generated schemas.
- Update protocol conversions, documentation, and existing test expectations for the revised metadata shape.
GitOrigin-RevId: f2b1304eadff661eec3966673ea71206b1542b98
## Why
Token-budget sessions need a final opportunity to preserve important state before the current context is compacted.
## What changed
- When `auto_compact_fallback_prompt` is configured, reserve `auto_compact_fallback_buffer_tokens` beyond the base auto-compaction limit.
- At the base limit, inject the fallback prompt once as a developer message while keeping the normal tool surface available. Continue reporting zero base-window tokens during this reserve.
- Roll over when the reserve or full model context is exhausted, and skip the fallback when a new context was already requested.
## Testing
Added coverage for using the fallback reserve, rolling over after it is exhausted, and bypassing the fallback for an explicit `new_context` request.
GitOrigin-RevId: 32983ecadc5cb4927e15ecd7b1e896cb52a9ad3b
## 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
## Why
Core filesystem permission models operate on native absolute paths, while exec
sandbox contexts must serialize paths as portable URIs.
## What changed
- Make the core filesystem permission and profile types concrete over
`AbsolutePathBuf` instead of generic over their path representation.
- Add exec-specific permission types that convert native permission paths to
`PathUri` values at the sandbox protocol boundary.
- Replace the legacy read/write-roots tuple with a named
`LegacyReadWriteRoots` struct.
## Testing
- Add coverage that exec sandbox permission paths serialize as URIs and round
trip through the filesystem protocol.
GitOrigin-RevId: a0ef5f8aba9bbfdf00a00fcc4f199314836bc85d
## What changed
Document that `exec_command.yield_time_ms` has an effective range of
2,000–30,000 ms on Windows, and update the tool specification test to match.
GitOrigin-RevId: aa20bbb2ad82d162d29d93f3bfbe1b970445f44e
## What changed
- Define `SleepItem` in `codex-extension-items` and carry `clock.sleep` events through `TurnItem::Extension`.
- Preserve sleep persistence, thread-history reconstruction, and the app-server's `type: "sleep"` schema while reusing the extension-owned type.
## Testing
- Add serialization coverage for the `clock.sleep` extension wire shape and its protocol wrapper.
- Update sleep lifecycle and thread-history tests to exercise the extension-owned item.
GitOrigin-RevId: 34bb33ed9b90a09bf4744aafdb56e019c717a168
## Why
The generic `yield_time_ms` description does not explain the Windows-specific
initial wait behavior or when callers should choose a shorter value.
## What changed
- Describe `yield_time_ms` on Windows as the maximum wait before a running
command returns a session ID, while commands that finish sooner still return
immediately.
- Recommend the 10-second default for ordinary commands and shorter waits for
intentionally long-lived or interactive processes.
- Keep the existing parameter description on other platforms.
## Testing
- Update the expected `exec_command` tool schema for both platform variants.
GitOrigin-RevId: 32f90b3a56604fcf1734cc81ba7ab2f0bec41643
## What changed
- Convert filtered MCP tool metadata into `CoreToolRuntime` instances before constructing the tool router.
- Pass those runtimes through the shared tool-planning path instead of maintaining separate direct and deferred MCP tool lists.
- Preserve MCP visibility, app policy filtering, and direct versus deferred exposure behavior.
GitOrigin-RevId: 67f7fbeecc2992318c859e038cd97938833911db
## 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
## What changed
- Return only each live agent's name and status from `list_agents`.
- Stop tracking the most recent task message in agent metadata.
GitOrigin-RevId: 91836fe8efad7ea6b7305f0b409081ec77419cfd
## 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
- Limit `request_plugin_install` guidance to explicitly requested plugins after tool search has been exhausted.
- Exclude adjacent capabilities, broad recommendations, and plugins that only seem potentially useful.
- Clarify that `plugin_id` is the parenthesized ID from `<recommended_plugins>` and prohibit parallel tool calls.
- Keep the recommendation context focused on listing available plugins while the tool specification owns the installation criteria.
## Testing
- Update tool specification tests to verify the stricter eligibility and serialization guidance.
GitOrigin-RevId: 6ebfdd864a76316ab59a0624dc4d7d3abda39a98
## What changed
- Limit Guardian reviewer sessions with an environment to `exec_command`,
`write_stdin`, and `view_image`.
- Exclude general tool sources from Guardian reviewer tool planning.
## Testing
- Extend the Guardian request snapshot test to assert the exact model-visible
tool list.
GitOrigin-RevId: 80ba7011c23c32d163aaad906087fac396cc70fa
## 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
## Why
`TurnContext` stored model and reasoning settings both as resolved turn fields and inside `CollaborationMode`, requiring the copies to stay synchronized when the model changed.
## What changed
- Store the mode and collaboration-mode developer instructions directly on `TurnContext`.
- Reconstruct `CollaborationMode` from those values plus the turn's current model and reasoning effort when callers need it.
- Read the mode directly for plan-mode checks, lifecycle events, and telemetry.
GitOrigin-RevId: b8fccafdd5d5cbccc84bc70d542588087ddf0093
## Why
Standalone web search can return structured result DTOs separately from its
model-facing text output. App-server clients need access to that data without
coupling Codex to every result type or field.
## What changed
- Preserve the optional `results` array from `/v1/alpha/search` as opaque JSON
through web-search completion events, thread history, and app-server
`webSearch` items.
- Keep responses from older endpoints compatible when `results` is absent, and
allow clients to ignore result types and fields they do not understand.
- Regenerate the protocol schemas and TypeScript definitions for the optional
field.
## Testing
- Cover responses with missing, empty, and forward-compatible result payloads.
- Verify standalone web-search results round-trip through app-server item
notifications and thread-item conversion.
GitOrigin-RevId: 739ef5694ece5733f7b8749ec41d6bfa3f33c8c5
## Why
Policy-blocked proxy requests must terminate the corresponding active tool call and preserve the correct approval result, including when multiple calls are running concurrently.
## What changed
- Resolve a blocked request's execution ID to its registered active network call before recording the policy denial.
- Preserve an outcome already recorded for that call, and cancel the owning call after storing a new denial.
## Testing
Expand network approval integration coverage for Guardian and user decisions, permission hooks, persisted policy amendments, concurrent calls, timeouts, cancellations, and unattributed proxy requests.
GitOrigin-RevId: 961901bbc07cc498309453ec78cda1a56ab00a4b
## What changed
- Mark `request_plugin_install` as not supporting parallel tool calls so install requests execute serially.
- Add a unit test covering the handler's parallel-call capability.
GitOrigin-RevId: 5f2c8184562bd776b0e527e5e258c61c604a0910
## What changed
Add a `command_category` tag to tool result telemetry for `exec_command` and
`shell_command` invocations. Classify parsed commands as `read`, `list_files`,
`search`, or `unknown`; use `mixed` when a script contains multiple categories.
GitOrigin-RevId: 1edacb38c7be9b03af4f2fc86746184f19067592
## What changed
- Add optional serialized Codex turn metadata to extension tool calls.
- Populate it from the current turn context and send it as the
`x-codex-turn-metadata` header on standalone web search requests.
## Testing
- Extend the app-server web search integration test to verify that client
metadata, including the model ID, reaches the standalone search request.
GitOrigin-RevId: c0950108d89a1d317ac94ccd23efcee72fffc6f0
## Why
Model overrides for `spawn_agent` must be compatible with the multi-agent backend used by the current turn.
## What changed
- Carry each model's multi-agent backend metadata into `ModelPreset`.
- Filter the advertised `spawn_agent` model overrides for multi-agent v2 and reject overrides assigned to another backend.
- Limit error suggestions to picker-visible, backend-compatible models.
## Testing
Added coverage for hiding incompatible models from the tool description and rejecting them during spawn validation.
GitOrigin-RevId: 22c12aba67df46e9743a74f019b72a1b8b76b308
## What changed
- Add the `features.multi_agent_v2.expose_spawn_agent_model_overrides` setting, enabled by default, to expose `model` and `reasoning_effort` on the v2 `spawn_agent` tool.
- Keep these controls available when other spawn metadata is hidden, while allowing them to be disabled independently.
- Add root-agent and subagent guidance that overrides require a partial or context-free fork and should only be used when explicitly authorized.
## Testing
- Cover configuration parsing and defaults, usage-hint preservation, and tool-schema behavior with override exposure enabled and disabled.
GitOrigin-RevId: 92370498108c96fbd51f32965624ce531e991d9a
## What changed
- Include permission instructions in Guardian review requests and let the review model use its configured tool mode and standard tool plan instead of a Guardian-specific direct-tool override.
- Refine the Guardian policy for tenant policy precedence, authorization scoring, prompt-injection handling, read-only investigation, and post-denial user approval.
- Simplify low-risk allow responses to `{"outcome":"allow"}` regardless of authorization scoring.
## Testing
- Update Guardian request-layout snapshots to cover the permission instructions included in initial and follow-up reviews.
GitOrigin-RevId: eb83571ef61f7b4e854c12e13e7163c6fab43f00
## What changed
- Add an optional `error` payload to `TurnCompleteEvent` and omit it when a turn completes without an error.
- Preserve the full terminal `ErrorEvent` through the turn lifecycle so the completion event includes the same error details emitted separately by `EventMsg::Error`.
## Testing
- Extend the stream-error integration test to verify that `TurnCompleteEvent` contains the emitted error and that the next turn can still proceed.
GitOrigin-RevId: 8d32942a44132763076130102d8b89ab356d59d0
## 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
## Why
Drive-shaped POSIX paths such as `/C:/workspace` can be mistaken for Windows
paths when an automatic approval request converts them from `PathUri`.
## What changed
- Keep approval paths as `PathUri` values together with their environment ID
until the automatic review request is built.
- Recover host-native paths for local working directories when strict
conversion cannot determine the path convention.
- Continue rejecting incompatible paths from remote environments.
## Testing
Add coverage for drive-shaped local POSIX paths, foreign remote paths, and
preserving apply-patch path URIs while building approval actions.
GitOrigin-RevId: 3fd31cfb4e8b46f9968ff66d5e986ca777430185
## What changed
- Run permission-request hooks before routing approvals to the automated reviewer or user, including when `strict_auto_review` is enabled.
- Centralize approval resolution so hook, automated-reviewer, and user decisions share rejection handling and report the correct telemetry source.
## Testing
- Add an integration test showing that an allow hook can approve a shell command during strict auto-review without invoking the automated reviewer.
GitOrigin-RevId: 18e9d76baee6cbae9d35ae517250f2f82270a9d2
## What changed
- Pass configured workspace roots from core to the exec server so filesystem and process sandbox permissions are materialized against the intended roots.
- Preserve an explicitly empty workspace-root list instead of treating the sandbox working directory as an implicit root.
- Initialize filesystem sandbox contexts with their working directory as the default workspace root.
## Testing
- Add end-to-end coverage for patch and command writes inside and outside workspace roots.
- Verify remote filesystem and process sandboxes do not grant access through an empty workspace-root list.
GitOrigin-RevId: 6684c8f7de50970b45a29e2a6323df954c96f9f6
## Why
Unified exec can drain process output multiple times while waiting for a command. Collecting those drains into an uncapped buffer allows large commands to exceed the output collection limit.
## What changed
- Accumulate drained output through the capped head/tail buffer so collection remains bounded while preserving the beginning and end of the stream.
- Include a `... N bytes omitted ...` marker when the collection cap drops output.
- Calculate the original token estimate from all observed bytes and preserve omission metadata through truncation and sandbox-denial responses.
## Testing
- Cover repeated drains, previously omitted output, omission markers, and large-output summaries.
GitOrigin-RevId: c6e2efeb875ed8f35914365eab7431f25fd3484c
## Why
Not every Codex distribution currently includes the
`codex-code-mode-host` companion binary. Enabling the process-host
feature should not make code mode unavailable on those surfaces while
packaging support is being completed.
## What changed
- Fall back to an in-process code-mode session only when spawning the
companion binary returns `io::ErrorKind::NotFound`.
- Keep permission, handshake, timeout, and other host failures visible
instead of silently falling back.
- Store the provider's owned-process/in-process choice as one
enum-backed state so later sessions reuse the fallback decision.
- Preserve the underlying spawn `io::Error` while retaining the host
path in the displayed error.
- Update provider, `CodeModeService`, and end-to-end coverage to verify
successful fallback execution.
## Test plan
- `just test -p codex-code-mode`
- `just test -p codex-core missing_process_host`
## Summary
Codex Apps file parameters are exposed to the model as local paths,
uploaded at execution time, and rewritten into provided-file payloads
before the MCP tool call.
The rewrite currently includes the documented optional fields
`mime_type` and `file_name` for every file parameter. Apps with strict
schemas can reject those fields when they are not declared.
## Changes
- Derive the supported optional file fields from each
`openai/fileParams` parameter's raw input schema before replacing it
with the model-visible local-path schema.
- Always include `download_url` and `file_id`.
- Include `mime_type` and `file_name` only when that specific file
parameter's schema accepts them, including schemas that allow additional
properties.
- Handle scalar and array file parameters, including items-only arrays,
composed schemas, and local JSON Schema references.
- Preserve the existing restriction that only the host-owned Codex Apps
MCP server can use this upload path.
This supports tools with different file contracts in the same app: one
parameter can accept the optional fields while another remains strict.
## Validation
- `just test -p codex-mcp`
- `just test -p codex-core mcp_openai_file`
- `just test -p codex-core codex_apps_file_params_`
- `just fix -p codex-mcp`
- `just fix -p codex-core`
- `just fmt`
- `git diff --check`
- Manually verified in the Codex Electron app that:
- a strict file schema receives only `download_url` and `file_id`
- a rich file schema also receives `mime_type` and `file_name`
Related: #31330
## Why
When MCP tools are deferred behind `tool_search`, Code mode keeps them
callable but omits their individual declarations from the initial `exec`
description. The shared MCP `CallToolResult` types were derived only
from directly rendered tools, so deferring every MCP tool also removed
the common response contract that models need to interpret MCP results.
This restores that contract without undoing the context savings from
deferred tool definitions. This is a follow-up to #29486.
## What changed
- Track deferred Code-mode tool definitions separately from directly
rendered definitions.
- Render the shared MCP type preamble when either direct or deferred MCP
tools are available.
- Keep deferred tool declarations out of the initial prompt.
- Add unit and integration coverage for deferred MCP tools.
## Testing
- `just test -p codex-code-mode-protocol`
- `just test -p codex-core
code_mode_only_guides_all_tools_search_and_calls_deferred_app_tools`
## Why
Auto-review performance is weaker because of confusing instructions
about sandbox permissions, and because it is given many tools which are
irrelevant to it.
## What
* Update the auto review prompt
* Remove the permissions_instructions developer message
* Only pass exec_tool and view_image tool to the reviewer
## Validation
`just fmt`
`cargo test -p codex-core --lib --quiet`
### summary
We want to pause code-mode from yielding back to the model when a
subcommand triggers an approval prompt. This means that all of these
previously inline blocking requests should also take out a
ElicitationService registration.
This also does some plumbing refactoring to request patch approval to
make it match the other `request_*_approval` methods in that it blocks
on the approval in the function instead of returning the oneshot
channel, this affords our ability to encapsulate the ElicitationService
registration via RAII.
Adds tests to confirm the blocking behavior for code_mode both in suite
tests and that the session holds them.
## Description
This PR removes the last path in core that emits `ExecCommandBegin` /
`ExecCommandEnd` directly.
Every command execution now starts and completes through canonical
`ItemStarted` / `ItemCompleted(TurnItem::CommandExecution)`. The
existing `HasLegacyEvent` compatibility layer still fans out Begin/End
afterward, so raw core event consumers and legacy rollout replay keep
seeing the same events.
`UnifiedExecInteraction` is dormant today. Live unified exec uses
`UnifiedExecStartup` for command lifecycle and `TerminalInteraction` for
`write_stdin` and polling, so this is code cleanup rather than a current
product behavior change. The main win is the code-level invariant where
all core flows emit `TurnItem` instead of legacy events.
## What changed
- Removed the `UnifiedExecInteraction` branches that emitted legacy
command events directly.
- Routed every command source through the existing canonical
`CommandExecution` lifecycle and compatibility fanout.
## Description
This PR migrates standalone web search onto the extension-owned
turn-item path introduced in #31283.
Standalone web search now emits `ExtensionItem::WebSearch` through
generic `TurnItem::Extension`, while app-server still exposes the
existing typed `ThreadItem::WebSearch` JSON shape. Hosted Responses API
web search stays on core-owned `TurnItem::WebSearch`.
## What changed
- Added `web_search::WebSearchItem` and `WebSearchAction` to
`codex-extension-items` under the stable `web.search` kind.
- Collapsed `ExtensionTurnItem` to generic `{ item, legacy_events }` now
that no typed extension special cases remain.
- Kept the existing `WebSearchBegin` / `WebSearchEnd` compatibility
events and canonical-first ordering.
- Updated app-server projection/history and generated TypeScript; the
app-server JSON schema is unchanged.
## Description
This PR adds a `codex-extension-items` crate for extension-owned
`TurnItem` schemas, and updates standalone image generation to start
using it via `TurnItem::Extension`.
This gives us a way to prevent Core from having to be aware of all
extension items. App-server still exposes the existing public
`ThreadItem::ImageGeneration` shape, now by wrapping the same shared
`image_generation::ImageGenerationItem` type.
The new `codex-extension-items` crate is necessary because the image gen
extension item is used by:
- `codex-image-generation-extension`, which produces it.
- `codex-tools / core`, which carry it generically.
- `codex-protocol`, which serializes it into lifecycle events and
rollouts.
- `app-server protocol`, which wraps it in public
`ThreadItem::ImageGeneration`
```
extension implementation
↓
codex-extension-items
↓
protocol / tools / app-server
```
We keep the hosted Responses API image generation as
`TurnItem::ImageGeneration` because core still owns its persistence and
legacy fanout.
### Before
Standalone image generation is implemented as an extension, but its item
representation previously lived in the core protocol. This sets the
precedent that core is aware of all extension items, which would be good
to avoid.
```
image-gen extension
→ constructs codex_protocol::ImageGenerationItem
→ emits ExtensionTurnItem::ImageGeneration
→ core matches ImageGeneration specially
→ protocol stores TurnItem::ImageGeneration
```
### After
```
image-gen extension
→ constructs extension-owned ImageGenerationItem
→ emits generic ExtensionItem
→ core transports/persists it generically
→ app-server wraps ImageGenerationItem as ThreadItem::ImageGeneration
```
Future extension items can have typed app-server APIs without adding a
new `TurnItem` variant, `ExtensionTurnItem` variant, or core emitter
match arm.
## What changed
- Added `codex-extension-items` with the closed `ExtensionItem` enum and
shared `image_generation::ImageGenerationItem` schema.
- Added generic `TurnItem::Extension(ExtensionItem)` and
`ExtensionTurnItem::Extension { item, legacy_events }` paths.
- Updated standalone image generation to emit a typed extension item and
provide its existing legacy `ImageGenerationBegin` /
`ImageGenerationEnd` events explicitly.
- Kept canonical lifecycle ordering: core emits `ItemStarted` /
`ItemCompleted` before extension-provided legacy events.
## Follow-up
Standalone web search still uses its typed special-case path. Migrating
it later would let `ExtensionTurnItem` collapse into a single
extension-item struct.
## Summary
- Rename the hosted web-search wire field to the canonical
`indexed_web_access` spelling.
- Preserve existing indexed-search behavior.
## Rollout
Merge and release only after server support for `indexed_web_access` is
fully deployed.
## Testing
- `just fmt`
- `just test -p codex-tools
web_search_tool_spec_serializes_expected_wire_shape`
- Blocking CI passed, including indexed web-search integration coverage.
Bryan Ashley