## Summary
Introduce a `CodeModeSession` interface for executing and managing
code-mode cells.
This moves cell lifecycle, callback delegation, termination, and
shutdown behind a session abstraction, while continuing to use the
existing in-process implementation, and the ability to implement an
external process one behind this interface.
A Codex session owns one `CodeModeSession`, which in turn owns its
running cells and stored code-mode state. Each cell is represented to
the caller as a `StartedCell`, exposing its cell ID and initial
response.
It also introduces a `CodeModeSessionDelegate` callback interface. A
session uses the delegate to invoke nested host tools and emit
notifications while a cell is running, allowing the runtime to
communicate with its owning Codex session without depending directly on
core turn handling.
<img width="2121" height="1001" alt="image"
src="https://github.com/user-attachments/assets/c349a819-2a59-485c-bda4-2caf68ac4c31"
/>
## Why
Some models need to select their code-execution behavior through model
catalog metadata. Models without that metadata must continue to follow
the existing `CodeMode` and `CodeModeOnly` feature flags, including when
a newer server sends an enum value this client does not recognize.
## What changed
- add optional `ModelInfo.tool_mode` metadata with `direct`,
`code_mode`, and `code_mode_only`
- treat omitted and unknown wire values as `None`
- resolve `None` from the existing feature flags
- carry the resolved `ToolMode` directly on `TurnContext`, outside
`Config`
- use the resolved value for turn creation, model switches, review
turns, tool planning, and code execution
## Coverage
- add protocol coverage for omitted, known, and unknown enum values
- add focused coverage for flag fallback and explicit metadata
overriding feature flags
- add core integration coverage that fetches remote model metadata
through `/v1/models` and verifies the outbound `/responses` tools for
explicit `direct` and `code_mode_only` selectors
## Stack
- followed by #25032
## Summary
- Clarify default, omission, and bounded behavior across built-in tool
schemas, including unified exec, classic shell, Code Mode exec/wait,
multi-agent, agent job, MCP resource, image, goal, plan, tool_search,
and test-sync fields.
- Convert update_plan status to an enum and add short field descriptions
where the schema previously relied on surrounding context.
- Remove the dedicated permission-approval schema test and keep only
updates to existing expected-spec tests.
## Validation
- Ran `just fmt`.
- Ran `git diff --check`.
- Did not run clippy or tests, per request.
Regression has been eval
[here](https://openai.slack.com/archives/C09GDSP1J9X/p1779905065496949)
and we proved there are no regressions
## Why
Older persisted rollouts can contain `input_image.detail` values of
`auto` or `low` from before `ImageDetail` was narrowed to
`high`/`original`. Current deserialization rejects those values, which
can make resume skip later compacted checkpoints and reconstruct an
oversized raw suffix before the next compaction attempt.
Confirmed Sentry reports fixed by this compatibility path:
- [CODEX-1H3F](https://openai.sentry.io/issues/7500642496/)
- [CODEX-1H6N](https://openai.sentry.io/issues/7501025347/)
- [CODEX-1JDP](https://openai.sentry.io/issues/7504549065/)
- [CODEX-1HW6](https://openai.sentry.io/issues/7503407986/)
## Background
[openai/codex#20693](https://github.com/openai/codex/pull/20693) added
image-detail plumbing for app-server `UserInput` so input images could
explicitly request `detail: original`. The Slack discussion behind that
PR was about ScreenSpot / bridge evals where user input images were
resized, while tool output images already had MCP/code-mode ways to
request image detail.
In review, the intended new API surface was narrowed to `high` and
`original`: default to `high`, allow `original` when callers need
unchanged image handling, and avoid encouraging new `auto` or `low`
usage. That policy still makes sense for newly emitted values.
The missing compatibility piece is persisted history. Older rollouts can
already contain `auto` and `low`, and resume reconstructs typed history
by deserializing those rollout records. Rejecting old values at that
boundary causes valid compacted checkpoints to be skipped. This PR
restores `auto` and `low` as real variants so old records deserialize
and round-trip without being rewritten as `high`, while product paths
can continue to default to `high` and avoid emitting `auto` for new
behavior.
## What changed
- Restored `ImageDetail::Auto` and `ImageDetail::Low` as first-class
protocol values.
- Preserved `auto`/`low` through rollout deserialization, MCP image
metadata, code-mode image output, and schema/type generation.
- Kept local image byte handling conservative: only `original` switches
to original-resolution loading; `auto`/`low`/`high` continue through the
resize-to-fit path while retaining their detail value.
- Added regression coverage for enum round-tripping and code-mode `low`
detail handling.
## Testing
- `just write-app-server-schema`
- `just test -p codex-protocol`
- `just test -p codex-tools`
- `just test -p codex-code-mode`
- `just test -p codex-app-server-protocol`
- `just test -p codex-core
suite::rmcp_client::stdio_image_responses_preserve_original_detail_metadata`
- `just test -p codex-core
suite::code_mode::code_mode_can_use_mcp_image_result_with_image_helper`
- Loaded broken rollouts on local fixed builds, and started/completed
new turns.
I also attempted `just test -p codex-core`; the local broad run did not
finish green: 2559 tests run, 2467 passed, 55 flaky, 91 failed, 1 timed
out. The failures were broad timeout/deadline failures across unrelated
areas; targeted changed-path core tests above passed.
## Summary
Change code-mode stored value updates to merge writes by key instead of
replacing the session's complete stored-value map after each cell
completes.
Previously, each cell received a snapshot of stored values and returned
the complete resulting map. When multiple cells ran concurrently, a
later completion could overwrite values written by another cell because
it committed an older snapshot.
This change moves stored-value ownership into `CodeModeService`:
- Each runtime starts from the service's current stored values.
- Runtime completion reports only keys written by that cell.
- The service merges those writes into the current stored-value map on
successful completion.
- Core no longer replaces its stored-value state from a cell result.
As a result, concurrently executing cells can update different stored
keys without clobbering one another.
The move into CodeModeService is motivated by a desire to have this
lifetime tied to a new lifetime object on that side in a subsequent PR.
# Why
`PreToolUse`, `PostToolUse`, and `updatedInput` coverage for local
function tools currently depends on each handler remembering to wire up
the hook contract itself. That makes coverage easy to miss as new
function tools are added, even though most of them share the same basic
shape: a model-facing function call with JSON arguments.
# What
This makes `CoreToolRuntime` provide the default hook contract for
ordinary local function tools:
- build generic `PreToolUse` and `PostToolUse` payloads from the
function tool name and arguments
- apply `updatedInput` rewrites back into function-tool arguments
through the same default path
- let tool outputs override the post-hook input or response when they
have a more stable hook-facing contract
The exceptions stay explicit:
- hosted tools remain outside the generic local function path
- code-mode `wait` and `write_stdin` opt out for now
- `PostToolUse` feedback replaces only the model-visible response, so
code mode keeps its typed tool result
With the generic path in place, the MCP and extension-tool adapters no
longer need their own duplicate pre/post hook plumbing. The new coverage
exercises the registry default plus end-to-end local function behavior
for pre-hook blocking, `updatedInput` rewriting, and post-hook context.
## Why
`ToolExecutor` is the runtime contract that keeps a callable tool and
its model-visible spec together. Leaving `spec()` optional lets a
registered runtime silently omit that half of the contract, and it also
overloads a missing spec as an exposure decision for tools that should
stay dispatchable without being shown to the model.
## What
- Make `ToolExecutor::spec()` required and update core, extension, and
test tool executors to return a concrete `ToolSpec`.
- Add `ToolExposure::Hidden` for dispatch-only tools. The legacy
`shell_command` runtime in unified-exec sessions now uses that explicit
exposure instead of hiding itself by omitting a spec.
- Build MCP tool specs when `McpHandler` is constructed so invalid MCP
specs are skipped before the handler is registered.
- Keep tool planning aligned with the new contract for direct, deferred,
hidden, code-mode, dynamic, and namespaced tool paths.
## Testing
- Added tool-plan coverage that invalid MCP tool specs are not
registered.
- Updated shell-family coverage for the hidden legacy `shell_command`
runtime and the affected tool executor test fixtures.
## Summary
- Add optional image detail to user image inputs across core, app-server
v2, thread history/event mapping, and the generated app-server
schemas/types.
- Preserve requested detail when serializing Responses image inputs:
omitted detail stays on the existing `high` default, while explicit
`original` keeps local images on the original-resolution path.
- Support `high`/`original` consistently for tool image outputs,
including MCP `codex/imageDetail`, code-mode image helpers, and
`view_image`.
## Why
The tool runtime path still had a typed output associated type on
`ToolExecutor`, plus a core-only `RegisteredTool` adapter and
extension-only executor aliases. That made every new shared tool runtime
carry extra adapter plumbing before it could participate in core
dispatch, extension tools, hook payloads, telemetry, and model-visible
spec generation.
This PR moves output erasure to the shared executor boundary so core and
extension tools can use the same execution contract directly.
## What Changed
- Changed `codex_tools::ToolExecutor` to return `Box<dyn ToolOutput>`
instead of an associated `Output` type.
- Removed the extension-specific `ExtensionToolExecutor` /
`ExtensionToolOutput` aliases and exposed `ToolExecutor<ToolCall>` plus
`ToolOutput` through `codex-extension-api`.
- Reworked core tool registration around `CoreToolRuntime` and
`ToolRegistry::from_tools`, removing the extra `RegisteredTool` /
`ToolRegistryBuilder` layer.
- Consolidated model-visible spec planning and registry construction in
`core/src/tools/spec_plan.rs`, including deferred tool search and
code-mode-only filtering.
- Added `ToolOutput` helpers for post-tool-use hook ids and inputs so
MCP, unified exec, extension, and other boxed outputs preserve the same
hook payload behavior.
- Updated core handlers, memories tools, and the related
registry/spec/router tests to use the simplified contract.
## Test Coverage
- Updated coverage for tool spec planning, registry lookup, deferred
tool search registration, extension tool routing, post-tool-use hook
payloads, dispatch tracing, guardian output extraction, and memories
extension tool execution.
## Why
`codex_tools::ToolExecutor` keeps a tool spec attached to its runtime
handler, but extension tools still carried a parallel
`ExtensionToolFuture` / `ExtensionToolExecutor` shape. That made
extension-owned tools look different from host tools even though
routing, registration, and execution need the same abstraction.
This PR makes the shared executor contract directly async and lets
extension tools implement it too, so host tools and extension tools can
move through the same registration path.
## What changed
- Changed `ToolExecutor::handle` to an `async fn` using `async-trait`,
and updated built-in tool handlers to implement the async trait
directly.
- Replaced the bespoke `ExtensionToolFuture` contract with a marker
`ExtensionToolExecutor` over `ToolExecutor<ToolCall, Output =
JsonToolOutput>`, re-exporting `ToolExecutor` from
`codex-extension-api`.
- Updated the memories extension tools to implement the shared executor
trait.
- Split tool-router construction into collected executors plus hosted
model specs, keeping hosted tools like web search and image generation
separate from executable handlers.
- Updated spec/router tests and extension-tool stubs for the new
executor shape.
## Verification
- Not run locally.
## Why
Codex still models model-visible tools and executable behavior largely
inside `codex-core`, which makes it harder to evolve the tool system
toward a single reusable abstraction for built-ins, MCP-backed tools,
dynamic tools, and later tools injected from outside core.
This PR takes the next incremental step in that direction by moving the
common execution-facing pieces out of core and separating them from
core-only orchestration. The intent is to let shared tool abstractions
improve in one place, while `codex-core` keeps the parts that are still
inherently host-specific today, such as `ToolInvocation`, dispatch
wiring, and hook integration.
This PR is mostly moving things around. The only interesting piece is
this abstraction:
https://github.com/openai/codex/pull/22359/changes#diff-81af519002548ba51ed102bdaaf77e081d40a1e73a6e5f9b104bbbc96a6f1b3dR13
## What changed
- Added `codex_tools::ToolExecutor<Invocation>` as the shared execution
trait for model-visible tools.
- Moved the reusable execution support types from `codex-core` into
`codex-tools`:
- `FunctionCallError`
- `ToolPayload`
- `ToolOutput`
- Refactored core tool implementations so that execution behavior lives
on `ToolExecutor<ToolInvocation>`, while `ToolHandler` remains the
core-local extension point for hook payloads, telemetry tags, diff
consumers, and other orchestration concerns.
- Kept the registry and dispatch flow behaviorally unchanged while
making the shared/extracted boundary explicit across built-in, MCP,
dynamic, extension-backed, shell, and multi-agent tool handlers.
## Verification
- `cargo test -p codex-tools`
- `just fix -p codex-tools`
- `just fix -p codex-core`
- `cargo test -p codex-core` progressed through the updated tool
surfaces and then hit the existing unrelated multi-agent stack overflow
in
`tools::handlers::multi_agents::tests::tool_handlers_cascade_close_and_resume_and_keep_explicitly_closed_subtrees_closed`.
## Summary
This refactor makes tool handlers the owner of the specs they can
publish, so registry construction can register handlers once and
separately publish only the specs that should be model-visible.
The main motivation is deferred tools: MCP and dynamic tools still need
handlers registered up front, but deferred tools should be discoverable
through `tool_search` rather than emitted in the initial tool spec list.
## What changed
- `McpHandler` and `DynamicToolHandler` can return their own `ToolSpec`.
- `build_tool_registry_builder` now collects handlers, registers them
through the no-spec path, and publishes only non-deferred handler specs.
- Deferred MCP and dynamic tool names are combined into one
`all_deferred_tools` set that drives spec filtering, code-mode
deferred-tool signaling, and `tool_search` registration.
- `tool_search` registration now requires both deferred tools and
`namespace_tools`.
- Namespace specs are merged in `spec_plan`, preserving top-level spec
order, sorting tools within each namespace, and backfilling empty
namespace descriptions.
- Hosted web search and image-generation specs are included in the
collected spec vector before namespace merge/publication, and tool-name
tests that should not care about hosted relative order now compare sets.
## Testing
- `cargo test -p codex-core tools::spec::tests:: -- --nocapture`
- `cargo test -p codex-core tools::spec_plan::tests:: -- --nocapture`
- `cargo test -p codex-core
tools::router::tests::specs_filter_deferred_dynamic_tools --
--nocapture`
- `cargo test -p codex-core
suite::prompt_caching::prompt_tools_are_consistent_across_requests --
--nocapture`
- `just fmt`
- `just fix -p codex-core`
- `cargo test -p codex-core -- --skip
tools::handlers::multi_agents::tests::tool_handlers_cascade_close_and_resume_and_keep_explicitly_closed_subtrees_closed`
passed the library suite after skipping the known stack-overflowing unit
test.
Full `cargo test -p codex-core` currently hits a stack overflow in
`tools::handlers::multi_agents::tests::tool_handlers_cascade_close_and_resume_and_keep_explicitly_closed_subtrees_closed`;
the same focused test reproduces on `origin/main`.
## Why
Code mode only used nested spec lookup at execution time to rediscover
whether a nested tool should be invoked as a function tool or a freeform
tool.
That information is already present in the enabled tool metadata that
code mode builds to expose `tools.*` and `ALL_TOOLS`, so re-looking it
up from the router was redundant and kept execution coupled to a
separate spec lookup path.
## What Changed
- thread `CodeModeToolKind` through the code-mode runtime `ToolCall`
event and `CodeModeNestedToolCall`
- emit the nested tool kind directly from the V8 callback using the
already-enabled tool metadata
- build nested tool payloads from the propagated kind instead of calling
`find_spec`
- remove the now-unused `find_spec` plumbing from the router and
parallel runtime helpers
- add unit coverage for function vs freeform payload shaping and update
affected router tests
## Testing
- `cargo test -p codex-code-mode`
- `cargo test -p codex-core code_mode::tests`
- `cargo test -p codex-core
extension_tool_bundles_are_model_visible_and_dispatchable`
- `cargo test -p codex-core
model_visible_specs_filter_deferred_dynamic_tools`
## Why
The MCP tool path had accumulated a few core-owned special cases: a
dedicated payload variant, resolver plumbing, a legacy `AfterToolUse`
translation path, and a side channel for parallel-call metadata. That
made `ToolRegistry` and the spec builder know more about MCP than they
needed to.
This change moves MCP-specific execution details back onto `ToolInfo`
and `McpHandler` so `codex-core` can treat MCP calls like normal
function calls while still preserving MCP-specific dispatch and
telemetry behavior where it belongs.
## What changed
- removed `resolve_mcp_tool_info`, `ToolPayload::Mcp`, `ToolKind`, and
the remaining registry-side MCP resolver path
- stored MCP routing metadata directly on `McpHandler` and `ToolInfo`,
including `supports_parallel_tool_calls`
- deleted the legacy `AfterToolUse` consumer in `core`, which removes
the need for handler-specific `after_tool_use_payload` implementations
- switched tool-result telemetry to handler-provided tags and kept
MCP-specific dispatch payload construction inside the handler
- simplified tool spec planning/building by passing `ToolInfo` directly
and dropping the direct/deferred MCP wrapper structs and the
parallel-server side table
## Testing
- `cargo check -p codex-core -p codex-mcp -p codex-otel`
- `cargo test -p codex-core
mcp_parallel_support_uses_exact_payload_server`
- `cargo test -p codex-core
direct_mcp_tools_register_namespaced_handlers`
- `cargo test -p codex-core
search_tool_description_lists_each_mcp_source_once`
- `cargo test -p codex-mcp
list_all_tools_uses_startup_snapshot_while_client_is_pending`
- `just fix -p codex-core -p codex-mcp -p codex-otel`
## Why
This is the next narrow step toward moving concrete tool families out of
core. After #22138 introduced `codex-tool-api`, we still needed a real
end-to-end seam that lets an extension own an executable tool definition
once and have core install it without the temporary `extension-api`
wrapper or a dependency on `codex-tools`.
`codex-tool-api` is the small extension-facing execution contract, while
`codex-tools` still has a different job: host-side shared tool metadata
and planning logic that is not “run this contributed tool”, like spec
shaping, namespaces, discovery, code-mode augmentation, and
MCP/dynamic-to-Responses API conversion
## What changed
- Moved the shared leaf tool-spec and JSON Schema types into
`codex-tool-api`, so the executable contract now lives with
[`ToolBundle`](https://github.com/openai/codex/blob/c538758095337d4fe0a52a172363ccede4066bda/codex-rs/tool-api/src/bundle.rs#L19-L70).
- Replaced the temporary extension-side tool wrapper with direct
`ToolBundle` use in `codex-extension-api`.
- Taught core to collect contributed bundles, include them in spec
planning, register them through
[`ToolRegistryBuilder::register_tool_bundle`](https://github.com/openai/codex/blob/c538758095337d4fe0a52a172363ccede4066bda/codex-rs/core/src/tools/registry.rs#L653-L667),
and dispatch them through the existing router/runtime path.
- Added focused coverage for contributed tools becoming model-visible
and dispatchable, plus spec-planning coverage for contributed function
and freeform tools.
## Verification
- Added `extension_tool_bundles_are_model_visible_and_dispatchable` in
`core/src/tools/router_tests.rs`.
- Added spec-plan coverage in `core/src/tools/spec_plan_tests.rs` for
contributed extension bundles.
## Related
- Follow-up to #22138
## Summary
In https://github.com/openai/codex/pull/21584, we disabled doctests for
crates that lack any doctests. We can enforce that property via `cargo
shear --deny-warnings`: crates that lack doctests will be flagged if
doctests are enabled, and crates with doctests will be flagged if
doctests are disabled.
A few additional notes:
- By adding `--deny-warnings`, `cargo shear` also flagged a number of
modules that were not reachable at all. Some of those have been removed.
- This PR removes a usage of `windows_modules!` (since `cargo shear` and
`rustfmt` couldn't see through it) in favor of simple `#[cfg(target_os =
"windows")]` macros. As a consequence, many of these files exhibit churn
in this PR, since they weren't being formatted by `rustfmt` at all on
main.
- Again, to make the code more analyzable, this PR also removes some
usages of `#[path = "cwd_junction.rs"]` in favor of a more standard
module structure. The bin sidecar structure is still retained, but,
e.g., `windows-sandbox-rs/src/bin/command_runner.rs` was moved to
`windows-sandbox-rs/src/bin/command_runner/main.rs`, and so on.
---------
Co-authored-by: Codex <noreply@openai.com>
## Why
This is the next stacked step after deleting the tool-handler kind
indirection. Specs should come from the registered handlers themselves
so registry construction has a single source of truth for handler
behavior and exposed tool definitions.
## What changed
- Added `ToolHandler::spec()` plus handler-provided parallel/code-mode
metadata, and made `ToolRegistryBuilder::register_handler` automatically
collect specs from registered handlers.
- Moved builtin tool spec construction into the corresponding handlers
and their adjacent `_spec` modules, including shell, unified exec, apply
patch, view image, request plugin install, tool search, MCP resource,
goals, planning, permissions, agent jobs, and multi-agent tools.
- Reworked configurable handlers to receive their tool-building options
through constructors, with non-optional handler options where the
handler is always spec-backed. Shell fallback handlers keep an explicit
no-spec mode because they are also registered as hidden dispatch
aliases.
- Kept `CodeModeExecuteHandler` on the explicit configured wrapper so
the code-mode exec spec can still be built from the nested registry.
## Verification
- `cargo check -p codex-core`
- `cargo test -p codex-core tools::spec_plan::tests`
- `cargo test -p codex-core tools::spec::tests`
- `cargo test -p codex-core tools::handlers::multi_agents_spec::tests`
- `RUST_MIN_STACK=16777216 cargo test -p codex-core
tools::handlers::multi_agents::tests`
- `cargo test -p codex-core tools::handlers::apply_patch::tests`
- `cargo test -p codex-core tools::handlers::unified_exec::tests`
- `just fix -p codex-core`
- `git diff --check`
## DISCLAIMER
This is experimental and no production service must rely on this
## Why
Built-in MCPs are product-owned runtime capabilities, but they were
previously flattened into the same config-backed stdio path as
user-configured servers. That made them depend on a hidden `codex
builtin-mcp` re-exec path, exposed them through config-oriented CLI
flows, and erased distinctions the runtime needs to preserve—most
notably whether an MCP call should count as external context for
memory-mode pollution.
## What changed
- Model product-owned built-ins separately from config-backed MCP
servers via `BuiltinMcpServer` and `EffectiveMcpServer`.
- Launch built-ins in process through a reusable async transport instead
of the hidden `builtin-mcp` stdio subcommand.
- Keep config-oriented CLI operations such as `codex mcp
list/get/login/logout` scoped to configured servers, while merging
built-ins only into the effective runtime server set.
- Retain server metadata after launch so parallel-tool support and
context classification come from the live server set; built-in
`memories` is now classified as local Codex state rather than external
context.
## Test plan
- `cargo test -p codex-mcp`
- `cargo test -p codex-core --test suite
builtin_memories_mcp_call_does_not_mark_thread_memory_mode_polluted_when_configured`
---------
Co-authored-by: Codex <noreply@openai.com>
## Why
This is the first mechanical slice of moving tool spec ownership toward
the handlers. `codex-tools` should keep shared primitives and conversion
helpers, while builtin tool specs and registration planning live in
`codex-core` with the handlers that own those tools.
Keeping this PR to relocation and import updates isolates the copy/move
review from the later logic change that wires specs through registered
handlers.
## What changed
- Moved builtin tool spec constructors from `codex-rs/tools/src` into
`codex-rs/core/src/tools/handlers/*_spec.rs` or nearby core tool
modules.
- Moved the registry planning code into
`codex-rs/core/src/tools/spec_plan.rs` and its associated types/tests
into core.
- Kept shared primitives in `codex-tools`, including `ToolSpec`,
schema/types, discovery/config primitives, dynamic/MCP conversion
helpers, and code-mode collection helpers.
- Updated handlers that referenced moved argument types or tool-name
constants to use the core spec modules.
- Moved spec tests next to the moved spec modules.
## Verification
- `cargo check -p codex-tools`
- `cargo check -p codex-core`
- `cargo test -p codex-tools`
- `cargo test -p codex-core _spec::tests`
- `cargo test -p codex-core tools::spec_plan::tests`
- `just fix -p codex-tools`
- `just fix -p codex-core`
Note: I also tried the broader `cargo test -p codex-core tools::`; it
reached the moved spec-plan/spec tests successfully, then aborted with a
stack overflow in
`tools::handlers::multi_agents::tests::tool_handlers_cascade_close_and_resume_and_keep_explicitly_closed_subtrees_closed`,
which is outside this spec relocation.
## Why
Tool registration used to bind a tool name to a handler externally,
which left ownership split between the registry plan and the handler
implementation. Some built-in handlers also multiplexed multiple in-core
tools by switching on the invoked tool name internally.
This moves the registry identity onto the handler itself and makes
built-in multi-tool areas use separate concrete handlers, so each
registered handler instance owns exactly one tool name and one dispatch
path.
## What Changed
- Added `ToolHandler::tool_name()` and changed
`ToolRegistryBuilder::register_handler` to derive the registry key from
the handler.
- Split built-in multiplexed handlers into concrete per-tool handlers
for unified exec, shell/local shell/container exec, MCP resources, goal
tools, and agent job tools.
- Kept name-carrying handler instances only where the runtime target is
inherently external or dynamic, such as MCP tools, dynamic tools, and
unavailable placeholders.
- Updated `ToolHandlerKind` and registry-plan construction so plan
entries map directly to concrete handler registrations.
## Verification
- `cargo test -p codex-tools tool_registry_plan`
- `cargo test -p codex-core --lib tools::registry_tests`
- `just fix -p codex-tools`
- `just fix -p codex-core`
## Summary
Adds the debug CLI entry point for reducing recorded rollout traces.
This gives developers a direct way to inspect whether the emitted trace
stream reduces into the expected conversation/runtime model.
## Stack
This is PR 5/5 in the rollout trace stack.
- [#18876](https://github.com/openai/codex/pull/18876): Add rollout
trace crate
- [#18877](https://github.com/openai/codex/pull/18877): Record core
session rollout traces
- [#18878](https://github.com/openai/codex/pull/18878): Trace tool and
code-mode boundaries
- [#18879](https://github.com/openai/codex/pull/18879): Trace sessions
and multi-agent edges
- [#18880](https://github.com/openai/codex/pull/18880): Add debug trace
reduction command
## Review Notes
This PR is intentionally last: it depends on the trace crate, core
recorder, runtime/tool events, and session/agent edge data all existing.
The command should remain a debug/developer tool and avoid adding new
runtime behavior.
The useful review question is whether the CLI exposes the reducer in the
smallest practical way for local inspection without turning the debug
command into a supported user-facing workflow.
## Summary
Extends rollout tracing across tool dispatch and code-mode runtime
boundaries. This records canonical tool-call lifecycle events and links
code-mode execution/wait operations back to the model-visible calls that
caused them.
## Stack
This is PR 3/5 in the rollout trace stack.
- [#18876](https://github.com/openai/codex/pull/18876): Add rollout
trace crate
- [#18877](https://github.com/openai/codex/pull/18877): Record core
session rollout traces
- [#18878](https://github.com/openai/codex/pull/18878): Trace tool and
code-mode boundaries
- [#18879](https://github.com/openai/codex/pull/18879): Trace sessions
and multi-agent edges
- [#18880](https://github.com/openai/codex/pull/18880): Add debug trace
reduction command
## Review Notes
This PR is about attribution. Reviewers should focus on whether direct
tool calls, code-mode-originated tool calls, waits, outputs, and
cancellation boundaries are recorded with enough source information for
deterministic reduction without coupling the reducer to live runtime
internals.
The stack remains valid after this layer: tool and code-mode traces
reduce through the existing crate model, while the broader session and
multi-agent relationships are added in the next PR.
## Why
This PR prepares the stack to enable Clippy await-holding lints that
were left disabled in #18178. The mechanical lock-scope cleanup is
handled separately; this PR is the documentation/configuration layer for
the remaining await-across-guard sites.
Without explicit annotations, reviewers and future maintainers cannot
tell whether an await-holding warning is a real concurrency smell or an
intentional serialization boundary.
## What changed
- Configures `clippy.toml` so `await_holding_invalid_type` also covers
`tokio::sync::{MutexGuard,RwLockReadGuard,RwLockWriteGuard}`.
- Adds targeted `#[expect(clippy::await_holding_invalid_type, reason =
...)]` annotations for intentional async guard lifetimes.
- Documents the main categories of intentional cases: active-turn state
transitions that must remain atomic, session-owned MCP manager accesses,
remote-control websocket serialization, JS REPL kernel/process
serialization, OAuth persistence, external bearer token refresh
serialization, and tests that intentionally serialize shared global or
session-owned state.
- For external bearer token refresh, documents the existing
serialization boundary: holding `cached_token` across the provider
command prevents concurrent cache misses from starting duplicate refresh
commands, and the current behavior is small enough that an explicit
expectation is easier to maintain than adding another synchronization
primitive.
## Verification
- `cargo clippy -p codex-login --all-targets`
- `cargo clippy -p codex-connectors --all-targets`
- `cargo clippy -p codex-core --all-targets`
- The follow-up PR #18698 enables `await_holding_invalid_type` and
`await_holding_lock` as workspace `deny` lints, so any undocumented
remaining offender will fail Clippy.
---
[//]: # (BEGIN SAPLING FOOTER)
Stack created with [Sapling](https://sapling-scm.com). Best reviewed
with [ReviewStack](https://reviewstack.dev/openai/codex/pull/18423).
* #18698
* __->__ #18423
## Summary
- honor `_meta["codex/imageDetail"] == "original"` on MCP image content
and map it to `detail: "original"` where supported
- strip that detail back out when the active model does not support
original-detail image inputs
- update code-mode `image(...)` to accept individual MCP image blocks
- teach `js_repl` / `codex.emitImage(...)` to preserve the same hint
from raw MCP image outputs
- document the new `_meta` contract and add generic RMCP-backed coverage
across protocol, core, code-mode, and js_repl paths
stacked on #17402.
MCP tools returned by `tool_search` (deferred tools) get registered in
our `ToolRegistry` with a different format than directly available
tools. this leads to two different ways of accessing MCP tools from our
tool catalog, only one of which works for each. fix this by registering
all MCP tools with the namespace format, since this info is already
available.
also, direct MCP tools are registered to responsesapi without a
namespace, while deferred MCP tools have a namespace. this means we can
receive MCP `FunctionCall`s in both formats from namespaces. fix this by
always registering MCP tools with namespace, regardless of deferral
status.
make code mode track `ToolName` provenance of tools so it can map the
literal JS function name string to the correct `ToolName` for
invocation, rather than supporting both in core.
this lets us unify to a single canonical `ToolName` representation for
each MCP tool and force everywhere to use that one, without supporting
fallbacks.
## Why
For more advanced MCP usage, we want the model to be able to emit
parallel MCP tool calls and have Codex execute eligible ones
concurrently, instead of forcing all MCP calls through the serial block.
The main design choice was where to thread the config. I made this
server-level because parallel safety depends on the MCP server
implementation. Codex reads the flag from `mcp_servers`, threads the
opted-in server names into `ToolRouter`, and checks the parsed
`ToolPayload::Mcp { server, .. }` at execution time. That avoids relying
on model-visible tool names, which can be incomplete in
deferred/search-tool paths or ambiguous for similarly named
servers/tools.
## What was added
Added `supports_parallel_tool_calls` for MCP servers.
Before:
```toml
[mcp_servers.docs]
command = "docs-server"
```
After:
```toml
[mcp_servers.docs]
command = "docs-server"
supports_parallel_tool_calls = true
```
MCP calls remain serial by default. Only tools from opted-in servers are
eligible to run in parallel. Docs also now warn to enable this only when
the server’s tools are safe to run concurrently, especially around
shared state or read/write races.
## Testing
Tested with a local stdio MCP server exposing real delay tools. The
model/Responses side was mocked only to deterministically emit two MCP
calls in the same turn.
Each test called `query_with_delay` and `query_with_delay_2` with `{
"seconds": 25 }`.
| Build/config | Observed | Wall time |
| --- | --- | --- |
| main with flag enabled | serial | `58.79s` |
| PR with flag enabled | parallel | `31.73s` |
| PR without flag | serial | `56.70s` |
PR with flag enabled showed both tools start before either completed;
main and PR-without-flag completed the first delay before starting the
second.
Also added an integration test.
Additional checks:
- `cargo test -p codex-tools` passed
- `cargo test -p codex-core
mcp_parallel_support_uses_exact_payload_server` passed
- `git diff --check` passed
- [x] Expand tool search to custom MCPs.
- [x] Rename several variables/fields to be more generic.
Updated tool & server name lifecycles:
**Raw Identity**
ToolInfo.server_name is raw MCP server name.
ToolInfo.tool.name is raw MCP tool name.
MCP calls route back to raw via parse_tool_name() returning
(tool.server_name, tool.tool.name).
mcpServerStatus/list now groups by raw server and keys tools by
Tool.name: mod.rs:599
App-server just forwards that grouped raw snapshot:
codex_message_processor.rs:5245
**Callable Names**
On list-tools, we create provisional callable_namespace / callable_name:
mcp_connection_manager.rs:1556
For non-app MCP, provisional callable name starts as raw tool name.
For codex-apps, provisional callable name is sanitized and strips
connector name/id prefix; namespace includes connector name.
Then qualify_tools() sanitizes callable namespace + name to ASCII alnum
/ _ only: mcp_tool_names.rs:128
Note: this is stricter than Responses API. Hyphen is currently replaced
with _ for code-mode compatibility.
**Collision Handling**
We do initially collapse example-server and example_server to the same
base.
Then qualify_tools() detects distinct raw namespace identities behind
the same sanitized namespace and appends a hash to the callable
namespace: mcp_tool_names.rs:137
Same idea for tool-name collisions: hash suffix goes on callable tool
name.
Final list_all_tools() map key is callable_namespace + callable_name:
mcp_connection_manager.rs:769
**Direct Model Tools**
Direct MCP tool declarations use the full qualified sanitized key as the
Responses function name.
The raw rmcp Tool is converted but renamed for model exposure.
**Tool Search / Deferred**
Tool search result namespace = final ToolInfo.callable_namespace:
tool_search.rs:85
Tool search result nested name = final ToolInfo.callable_name:
tool_search.rs:86
Deferred tool handler is registered as "{namespace}:{name}":
tool_registry_plan.rs:248
When a function call comes back, core recombines namespace + name, looks
up the full qualified key, and gets the raw server/tool for MCP
execution: codex.rs:4353
**Separate Legacy Snapshot**
collect_mcp_snapshot_from_manager_with_detail() still returns a map
keyed by qualified callable name.
mcpServerStatus/list no longer uses that; it uses
McpServerStatusSnapshot, which is raw-inventory shaped.
## Why
This is another small step in the `codex-core` -> `codex-tools`
migration described in `AGENTS.md`.
`core/src/tools/spec.rs` and `core/src/tools/code_mode/mod.rs` were both
hand-rolling the same pure transformation: convert visible `ToolSpec`s
into code-mode nested tool definitions, then sort and deduplicate by
tool name. That logic does not depend on core runtime state or handlers,
so keeping it in `codex-core` makes `spec.rs` harder to peel out later
than it needs to be.
## What Changed
- Add `collect_code_mode_tool_definitions()` to
`codex-rs/tools/src/code_mode.rs`.
- Reuse that helper from `codex-rs/core/src/tools/spec.rs` when
assembling the `exec` tool description.
- Reuse the same helper from `codex-rs/core/src/tools/code_mode/mod.rs`
when exposing nested tool metadata to the code-mode runtime.
This is intended to be a straight refactor with no behavior change and
no new test surface.
## Verification
- `cargo test -p codex-tools`
- `cargo test -p codex-core tools::spec::tests`
- `cargo test -p codex-core code_mode_only_`
## Why
`codex-rs/core/src/client_common.rs` still had a `tools` re-export
module that forwarded `codex_tools` types back into `codex-core`. After
the earlier extraction work in #16379, #16471, #16477, and #16481, that
extra layer no longer adds value.
Removing it keeps dependencies explicit: the `codex-core` modules that
actually use `ToolSpec` and related types now depend on `codex_tools`
directly instead of reaching through `client_common`.
## What Changed
- removed the `client_common::tools` re-export module from
`core/src/client_common.rs`
- updated the remaining `codex-core` consumers to import `codex_tools`
directly
- adjusted the affected test code to reference
`codex_tools::ResponsesApiTool` directly as well
This is a mechanical cleanup only. It does not change tool behavior or
runtime logic.
## Testing
- `cargo test -p codex-core client_common::tests`
- `cargo test -p codex-core tools::router::tests`
- `cargo test -p codex-core tools::context::tests`
- `cargo test -p codex-core tools::spec::tests`
## Why
The longer-term `codex-tools` migration is to move pure tool-definition
and tool-spec plumbing out of `codex-core` while leaving session- and
runtime-coupled orchestration behind.
The remaining code-mode adapter layer in
`core/src/tools/code_mode_description.rs` was a good next extraction
seam because it only transformed `ToolSpec` values for code mode and
already delegated the low-level description rendering to
`codex-code-mode`.
## What Changed
- added `codex-rs/tools/src/code_mode.rs` with
`augment_tool_spec_for_code_mode()` and
`tool_spec_to_code_mode_tool_definition()`
- added focused unit coverage in `codex-rs/tools/src/code_mode_tests.rs`
- rewired `core/src/tools/spec.rs` and `core/src/tools/code_mode/mod.rs`
to use the extracted adapters from `codex-tools`
- removed the old `core/src/tools/code_mode_description.rs` shim and its
test file from `codex-core`
- added the `codex-code-mode` dependency to `codex-tools`, updated
`Cargo.lock`, and refreshed the `codex-tools` README to reflect the
expanded boundary
## Test Plan
- `cargo test -p codex-tools`
- `CARGO_TARGET_DIR=/tmp/codex-core-code-mode-adapters cargo test -p
codex-core --lib tools::spec::`
- `CARGO_TARGET_DIR=/tmp/codex-core-code-mode-adapters cargo test -p
codex-core --lib tools::code_mode::`
- `just bazel-lock-update`
- `just bazel-lock-check`
- `just argument-comment-lint`
## References
- #15923
- #15928
- #15944
- #15953
- #16031
- #16047
- #16129
- move the shared byte-based middle truncation logic from `core` into
`codex-utils-string`
- keep token-specific truncation in `codex-core` so rollout can reuse
the shared helper in the next stacked PR
---------
Co-authored-by: Codex <noreply@openai.com>
Moves Code Mode to a new crate with no dependencies on codex. This
create encodes the code mode semantics that we want for lifetime,
mounting, tool calling.
The model-facing surface is mostly unchanged. `exec` still runs raw
JavaScript, `wait` still resumes or terminates a `cell_id`, nested tools
are still available through `tools.*`, and helpers like `text`, `image`,
`store`, `load`, `notify`, `yield_control`, and `exit` still exist.
The major change is underneath that surface:
- Old code mode was an external Node runtime.
- New code mode is an in-process V8 runtime embedded directly in Rust.
- Old code mode managed cells inside a long-lived Node runner process.
- New code mode manages cells in Rust, with one V8 runtime thread per
active `exec`.
- Old code mode used JSON protocol messages over child stdin/stdout plus
Node worker-thread messages.
- New code mode uses Rust channels and direct V8 callbacks/events.
This PR also fixes the two migration regressions that fell out of that
substrate change:
- `wait { terminate: true }` now waits for the V8 runtime to actually
stop before reporting termination.
- synchronous top-level `exit()` now succeeds again instead of surfacing
as a script error.
---
- `core/src/tools/code_mode/*` is now mostly an adapter layer for the
public `exec` / `wait` tools.
- `code-mode/src/service.rs` owns cell sessions and async control flow
in Rust.
- `code-mode/src/runtime/*.rs` owns the embedded V8 isolate and
JavaScript execution.
- each `exec` spawns a dedicated runtime thread plus a Rust
session-control task.
- helper globals are installed directly into the V8 context instead of
being injected through a source prelude.
- helper modules like `tools.js` and `@openai/code_mode` are synthesized
through V8 module resolution callbacks in Rust.
---
Also added a benchmark for showing the speed of init and use of a code
mode env:
```
$ cargo bench -p codex-code-mode --bench exec_overhead -- --samples 30 --warm-iterations 25 --tool-counts 0,32,128
Finished [`bench` profile [optimized]](https://doc.rust-lang.org/cargo/reference/profiles.html#default-profiles) target(s) in 0.18s
Running benches/exec_overhead.rs (target/release/deps/exec_overhead-008c440d800545ae)
exec_overhead: samples=30, warm_iterations=25, tool_counts=[0, 32, 128]
scenario tools samples warmups iters mean/exec p95/exec rssΔ p50 rssΔ max
cold_exec 0 30 0 1 1.13ms 1.20ms 8.05MiB 8.06MiB
warm_exec 0 30 1 25 473.43us 512.49us 912.00KiB 1.33MiB
cold_exec 32 30 0 1 1.03ms 1.15ms 8.08MiB 8.11MiB
warm_exec 32 30 1 25 509.73us 545.76us 960.00KiB 1.30MiB
cold_exec 128 30 0 1 1.14ms 1.19ms 8.30MiB 8.34MiB
warm_exec 128 30 1 25 575.08us 591.03us 736.00KiB 864.00KiB
memory uses a fresh-process max RSS delta for each scenario
```
---------
Co-authored-by: Codex <noreply@openai.com>
- Split the feature system into a new `codex-features` crate.
- Cut `codex-core` and workspace consumers over to the new config and
warning APIs.
Co-authored-by: Ahmed Ibrahim <219906144+aibrahim-oai@users.noreply.github.com>
Co-authored-by: Codex <noreply@openai.com>
Cleanup image semantics in code mode.
`view_image` now returns `{image_url:string, details?: string}`
`image()` now allows both string parameter and `{image_url:string,
details?: string}`
Summary
- document that code mode only exposes `exec` and the renamed `wait`
tool
- update code mode tool spec and descriptions to match the new tool name
- rename tests and helper references from `exec_wait` to `wait`
Testing
- Not run (not requested)
## Why
Once the repo-local lint exists, `codex-rs` needs to follow the
checked-in convention and CI needs to keep it from drifting. This commit
applies the fallback `/*param*/` style consistently across existing
positional literal call sites without changing those APIs.
The longer-term preference is still to avoid APIs that require comments
by choosing clearer parameter types and call shapes. This PR is
intentionally the mechanical follow-through for the places where the
existing signatures stay in place.
After rebasing onto newer `main`, the rollout also had to cover newly
introduced `tui_app_server` call sites. That made it clear the first cut
of the CI job was too expensive for the common path: it was spending
almost as much time installing `cargo-dylint` and re-testing the lint
crate as a representative test job spends running product tests. The CI
update keeps the full workspace enforcement but trims that extra
overhead from ordinary `codex-rs` PRs.
## What changed
- keep a dedicated `argument_comment_lint` job in `rust-ci`
- mechanically annotate remaining opaque positional literals across
`codex-rs` with exact `/*param*/` comments, including the rebased
`tui_app_server` call sites that now fall under the lint
- keep the checked-in style aligned with the lint policy by using
`/*param*/` and leaving string and char literals uncommented
- cache `cargo-dylint`, `dylint-link`, and the relevant Cargo
registry/git metadata in the lint job
- split changed-path detection so the lint crate's own `cargo test` step
runs only when `tools/argument-comment-lint/*` or `rust-ci.yml` changes
- continue to run the repo wrapper over the `codex-rs` workspace, so
product-code enforcement is unchanged
Most of the code changes in this commit are intentionally mechanical
comment rewrites or insertions driven by the lint itself.
## Verification
- `./tools/argument-comment-lint/run.sh --workspace`
- `cargo test -p codex-tui-app-server -p codex-tui`
- parsed `.github/workflows/rust-ci.yml` locally with PyYAML
---
* -> #14652
* #14651
- **Summary**
- expose `exit` through the code mode bridge and module so scripts can
stop mid-flight
- surface the helper in the description documentation
- add a regression test ensuring `exit()` terminates execution cleanly
- **Testing**
- Not run (not requested)
Summary
- add the code_mode_only feature flag/config schema and wire its
dependency on code_mode
- update code mode tool descriptions to list nested tools with detailed
headers
- restrict available tools for prompt and exec descriptions when
code_mode_only is enabled and test the behavior
Testing
- Not run (not requested)
This change moves code_mode exec session settings out of the runtime API
and into an optional first-line pragma, so instead of calling runtime
helpers like set_yield_time() or set_max_output_tokens_per_exec_call(),
the model can write // @exec: {"yield_time_ms": ...,
"max_output_tokens": ...} at the top of the freeform exec source. Rust
now parses that pragma before building the source, validates it, and
passes the values directly in the exec start message to the code-mode
broker, which applies them at session start without any worker-runtime
mutation path. The @openai/code_mode module no longer exposes those
setter functions, the docs and grammar were updated to describe the
pragma form, and the existing code_mode tests were converted to use
pragma-based configuration instead.
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