## Why
Tool exposure is a planning concern, but the deferred MCP path and
dispatch-only legacy shell path were carrying those decisions in handler
constructors and a shell-only tool-family builder. Keeping those
decisions in `spec_plan` makes the core tool plan easier to follow and
keeps handlers focused on runtime behavior.
## What changed
- add `PlannedTools` helpers for ordinary runtimes, exposure overrides,
dispatch-only runtimes, and hosted specs
- inline shell tool assembly into `core/src/tools/spec_plan.rs` and
remove the shell-only `tool_family` module
- remove exposure state and special exposure constructors from
`McpHandler` and `ShellCommandHandler`
- keep hidden runtime behavior centralized in `ExposureOverride`,
including disabling parallel tool calls for hidden handlers
## Testing
- Not run (refactor only)
## Why
`codex-tools` is meant to hold reusable tool primitives, but
`ToolsConfig` had become a second copy of core runtime decisions instead
of a small shared contract. It carried provider capabilities, auth/model
gates, permission and environment state, web/search/image feature gates,
multi-agent settings, and goal availability from core into `codex-tools`
([definition](https://github.com/openai/codex/blob/22dd9ad3929253ed24d7ee4f10f238e95ab25f37/codex-rs/tools/src/tool_config.rs#L97),
[stored on each
`TurnContext`](https://github.com/openai/codex/blob/22dd9ad3929253ed24d7ee4f10f238e95ab25f37/codex-rs/core/src/session/turn_context.rs#L87)).
Every session/context variant then had to build and mutate that snapshot
before assembling tools.
This PR removes that master object instead of renaming it. Tool planning
now reads the live `TurnContext`, where `codex-core` already owns those
decisions, while `codex-tools` keeps only reusable primitives and a
generic `ToolSetBuilder`/`ToolSet` accumulator.
## What Changed
- Removed `ToolsConfig` / `ToolsConfigParams` from `codex-tools`; the
crate keeps the shared helpers that still belong there, including
request-user-input mode selection, shell backend/type resolution,
`UnifiedExecShellMode`, and `ToolEnvironmentMode`.
- Replaced config-snapshot planning with `ToolRouter::from_turn_context`
and a `spec_plan` pipeline over `CoreToolPlanContext`, deriving provider
capabilities, auth gates, model support, feature gates, environment
count, goal support, multi-agent options, web search, and image
generation from the authoritative turn state.
- Added generic `codex_tools::ToolSetBuilder` / `ToolSet`, plus the
small core adapter needed to accumulate `CoreToolRuntime` values and
hosted model specs.
- Added the `tool_family::shell` registration module and moved
shell/unified-exec/memory accounting call sites to read the narrow
per-turn fields directly.
- Narrowed `TurnContext` to the remaining explicit per-turn fields
needed by planning: `available_models`, `unified_exec_shell_mode`, and
`goal_tools_supported`.
- Reworked MCP exposure and tool-search setup so deferred/direct MCP
behavior is driven by the current turn rather than a precomputed config
snapshot.
- Replaced the large expected-spec fixture tests with focused
behavior-level coverage for shell tools, environments, goal and
agent-job gates, MCP direct/deferred exposure, tool search,
request-plugin-install, code mode, multi-agent mode, hosted tools, and
extension executor dispatch.
## Verification
- `cargo check -p codex-tools`
- `cargo check -p codex-core --lib`
- `cargo test -p codex-tools`
- `cargo test -p codex-core spec_plan --lib`
- `cargo test -p codex-core router --lib`
## Why
Extensions that need to track runtime progress currently have no typed
host signal for tool execution. The goal extension in particular needs
to observe tool attempts without inspecting tool payloads, owning tool
implementations, or staying coupled to core-only runtime plumbing.
This adds a narrow lifecycle contributor API for host-owned tool
execution: extensions can observe when an accepted tool call starts and
how it finishes, while policy hooks and tool handlers continue to own
payload rewriting, blocking, and execution.
Relevant code:
-
[`ToolLifecycleContributor`](https://github.com/openai/codex/blob/3ad2850ffc7d8a1da19c65a92425637a59098f1b/codex-rs/ext/extension-api/src/contributors.rs#L119)
defines the extension-facing observer contract.
-
[`tool_lifecycle.rs`](https://github.com/openai/codex/blob/3ad2850ffc7d8a1da19c65a92425637a59098f1b/codex-rs/ext/extension-api/src/contributors/tool_lifecycle.rs)
defines the typed start/finish inputs, source, and outcome enums.
- [`notify_tool_start` /
`notify_tool_finish`](https://github.com/openai/codex/blob/3ad2850ffc7d8a1da19c65a92425637a59098f1b/codex-rs/core/src/tools/lifecycle.rs)
bridges core tool dispatch into the extension registry.
## What Changed
- Added `ToolLifecycleContributor` to `codex-extension-api`, including:
- `ToolStartInput`
- `ToolFinishInput`
- `ToolCallSource`
- `ToolCallOutcome`
- Added registration and lookup support on `ExtensionRegistryBuilder` /
`ExtensionRegistry`.
- Wired core tool dispatch to notify lifecycle contributors for:
- accepted tool starts
- completed tool calls, including the tool output success marker
- pre-tool-use blocks
- failures before or after the handler runs
- cancellation/abort in the parallel tool path
- Registered the goal extension as a lifecycle contributor and added the
outcome filter it will use for goal progress accounting.
## Test Coverage
- Added `dispatch_notifies_tool_lifecycle_contributors` to cover
lifecycle notification ordering and outcomes for successful and
handler-failed tool calls.
## Why
The client and tool pipeline still carried compatibility code for legacy
structured shell output. Current shell and apply_patch responses are
already plain text for model consumption, so keeping a
JSON-serialization path plus shell-item rewrite logic makes the request
formatter and tests preserve a format we do not need anymore.
## What Changed
- Removed the client-side shell output rewrite from
`core/src/client_common.rs`.
- Removed the structured exec-output formatter and the shell `freeform`
switch so tool emitters use one model-facing formatter.
- Collapsed apply_patch/shell serialization tests around the remaining
plain-text output expectations and removed duplicate one-variant
parameterized cases.
- Kept the `ApplyPatchModelOutput::ShellCommandViaHeredoc` compatibility
input shape, but no longer treats it as a separate output-format mode.
## Validation
- `cargo test -p codex-core client_common`
- `cargo test -p codex-core shell_serialization`
- `cargo test -p codex-core apply_patch_cli`
- `just fix -p codex-core`
## Documentation
No external Codex documentation update is needed.
## Summary
- move tool_user_shell_type out of the old tools::spec module and call
it from tools directly
- attach the remaining spec planning model tests under spec_plan
- delete core/src/tools/spec.rs
## Tests
- just fmt
- cargo test -p codex-core tools::spec_plan
Note: a broader cargo test -p codex-core run on the earlier PR-head
worktree still hit the pre-existing stack overflow in
agent::control::tests::spawn_agent_fork_last_n_turns_keeps_only_recent_turns.
## 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
`ToolName::display()` made it too easy to flatten tool identity and
accidentally compare rendered strings. Tool identity should stay
structural until a legacy string boundary actually requires the
flattened spelling.
## What
- Removes `ToolName::display()` and relies on the existing `Display`
impl for messages and errors.
- Adds structural ordering for `ToolName` and uses it for
sorting/deduping deferred tools.
- Carries `ToolName` through tool/sandbox plumbing, flattening only at
legacy boundaries such as hook payloads, telemetry tags, and Responses
tool names.
- Updates MCP normalization tests to assert `ToolName` structure instead
of rendered strings.
## Testing
- `cargo test -p codex-mcp test_normalize_tools`
- `cargo test -p codex-core unavailable_tool`
- `just fix -p codex-protocol`
- `just fix -p codex-mcp`
- `just fix -p codex-core`
## 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.
## 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.
Fixes https://github.com/openai/codex/issues/16732.
## Why
`apply_patch` is Codex's primary file edit path, but it was not emitting
`PreToolUse` or `PostToolUse` hook events. That meant hook-based policy,
auditing, and write coordination could observe shell commands while
missing the actual file mutation performed by `apply_patch`.
The issue also exposed that the hook runtime serialized command hook
payloads with `tool_name: "Bash"` unconditionally. Even if `apply_patch`
supplied hook payloads, hooks would either fail to match it directly or
receive misleading stdin that identified the edit as a Bash tool call.
## What Changed
- Added `PreToolUse` and `PostToolUse` payload support to
`ApplyPatchHandler`.
- Exposed the raw patch body as `tool_input.command` for both
JSON/function and freeform `apply_patch` calls.
- Taught tool hook payloads to carry a handler-supplied hook-facing
`tool_name`.
- Preserved existing shell compatibility by continuing to emit `Bash`
for shell-like tools.
- Serialized the selected hook `tool_name` into hook stdin instead of
hardcoding `Bash`.
- Relaxed the generated hook command input schema so `tool_name` can
represent tools other than `Bash`.
## Verification
Added focused handler coverage for:
- JSON/function `apply_patch` calls producing a `PreToolUse` payload.
- Freeform `apply_patch` calls producing a `PreToolUse` payload.
- Successful `apply_patch` output producing a `PostToolUse` payload.
- Shell and `exec_command` handlers continuing to expose `Bash`.
Added end-to-end hook coverage for:
- A `PreToolUse` hook matching `^apply_patch$` blocking the patch before
the target file is created.
- A `PostToolUse` hook matching `^apply_patch$` receiving the patch
input and tool response, then adding context to the follow-up model
request.
- Non-participating tools such as the plan tool continuing not to emit
`PreToolUse`/`PostToolUse` hook events.
Also validated manually with a live `codex exec` smoke test using an
isolated temp workspace and temp `CODEX_HOME`. The smoke test confirmed
that a real `apply_patch` edit emits `PreToolUse`/`PostToolUse` with
`tool_name: "apply_patch"`, a shell command still emits `tool_name:
"Bash"`, and a denying `PreToolUse` hook prevents the blocked patch file
from being created.
## Summary
- Normalize deferred MCP and dynamic tools into `ToolSearchEntry` values
before constructing `ToolSearchHandler`.
- Move the tool-search entry adapter out of `tools/handlers` and into
`tools/tool_search_entry.rs` so the handlers directory stays focused on
handlers.
- Keep `ToolSearchHandler` operating over one generic entry list for
BM25 search, namespace grouping, and per-bucket default limits.
## Why
Follow-up cleanup for #17849. The dynamic tool-search support made the
handler juggle source-specific MCP and dynamic tool lists, index
arithmetic, output conversion, and namespace emission. This keeps source
adaptation outside the handler so the search loop itself is smaller and
source-agnostic.
## Validation
- `just fmt`
- `cargo test -p codex-core tools::handlers::tool_search::tests`
- `git diff --check`
- `cargo test -p codex-core` currently fails in unrelated
`plugins::manager::tests::list_marketplaces_ignores_installed_roots_missing_from_config`;
rerunning that single test fails the same way at
`core/src/plugins/manager_tests.rs:1692`.
---------
Co-authored-by: pash <pash@openai.com>
## Summary
- reduce public module visibility across Rust crates, preferring private
or crate-private modules with explicit crate-root public exports
- update external call sites and tests to use the intended public crate
APIs instead of reaching through module trees
- add the module visibility guideline to AGENTS.md
## Validation
- `cargo check --workspace --all-targets --message-format=short` passed
before the final fix/format pass
- `just fix` completed successfully
- `just fmt` completed successfully
- `git diff --check` passed
Stacked on #16508.
This removes the temporary `codex-core` / `codex-login` re-export shims
from the ownership split and rewrites callsites to import directly from
`codex-model-provider-info`, `codex-models-manager`, `codex-api`,
`codex-protocol`, `codex-feedback`, and `codex-response-debug-context`.
No behavior change intended; this is the mechanical import cleanup layer
split out from the ownership move.
---------
Co-authored-by: Codex <noreply@openai.com>
## Why
`#16193` moved the pure `tool_search` and `tool_suggest` spec builders
into `codex-tools`, but `codex-core` still owned the shared
discoverable-tool model that those builders and the `tool_suggest`
runtime both depend on. This change continues the migration by moving
that reusable model boundary out of `codex-core` as well, so the
discovery/suggestion stack uses one shared set of types and
`core/src/tools` no longer needs its own `discoverable.rs` module.
## What changed
- Moved `DiscoverableTool`, `DiscoverablePluginInfo`, and
`filter_tool_suggest_discoverable_tools_for_client()` into
`codex-rs/tools/src/tool_discovery.rs` alongside the extracted
discovery/suggestion spec builders.
- Added `codex-app-server-protocol` as a `codex-tools` dependency so the
shared discoverable-tool model can own the connector-side `AppInfo`
variant directly.
- Updated `core/src/tools/handlers/tool_suggest.rs`,
`core/src/tools/spec.rs`, `core/src/tools/router.rs`,
`core/src/connectors.rs`, and `core/src/codex.rs` to consume the shared
`codex-tools` model instead of the old core-local declarations.
- Changed `core/src/plugins/discoverable.rs` to return
`DiscoverablePluginInfo` directly, moved the pure client-filter coverage
into `tool_discovery_tests.rs`, and deleted the old
`core/src/tools/discoverable.rs` module.
- Updated `codex-rs/tools/README.md` so the crate boundary documents
that `codex-tools` now owns the discoverable-tool models in addition to
the discovery/suggestion spec builders.
## Test plan
- `cargo test -p codex-tools`
- `CARGO_TARGET_DIR=/tmp/codex-core-discoverable-model cargo test -p
codex-core --lib tools::handlers::tool_suggest::`
- `CARGO_TARGET_DIR=/tmp/codex-core-discoverable-model cargo test -p
codex-core --lib tools::spec::`
- `CARGO_TARGET_DIR=/tmp/codex-core-discoverable-model cargo test -p
codex-core --lib plugins::discoverable::`
- `just bazel-lock-check`
- `just argument-comment-lint`
## References
- #16193
- #16154
- #15923
- #15928
- #15944
- #15953
- #16031
- #16047
- #16129
- #16132
- #16138
- #16141
## 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>
### Description
#### Summary
Introduces the core plumbing required for structured network approvals
#### What changed
- Added structured network policy decision modeling in core.
- Added approval payload/context types needed for network approval
semantics.
- Wired shell/unified-exec runtime plumbing to consume structured
decisions.
- Updated related core error/event surfaces for structured handling.
- Updated protocol plumbing used by core approval flow.
- Included small CLI debug sandbox compatibility updates needed by this
layer.
#### Why
establishes the minimal backend foundation for network approvals without
yet changing high-level orchestration or TUI behavior.
#### Notes
- Behavior remains constrained by existing requirements/config gating.
- Follow-up PRs in the stack handle orchestration, UX, and app-server
integration.
---------
Co-authored-by: Codex <199175422+chatgpt-codex-connector[bot]@users.noreply.github.com>
Instead of returning structured out and then re-formatting it into
freeform, return the freeform output from shell_command tool.
Keep `shell` as the default tool for GPT-5.
- This PR is to make it on path for truncating by tokens. This path will
be initially used by unified exec and context manager (responsible for
MCP calls mainly).
- We are exposing new config `calls_output_max_tokens`
- Use `tokens` as the main budget unit but truncate based on the model
family by Introducing `TruncationPolicy`.
- Introduce `truncate_text` as a router for truncation based on the
mode.
In next PRs:
- remove truncate_with_line_bytes_budget
- Add the ability to the model to override the token budget.
This is just a refactor of `conversation_history` file by breaking it up
into multiple smaller ones with helper. This refactor will help us move
more functionality related to context management here. in a clean way.
move the truncation logic to conversation history to use on any tool
output. This will help us in avoiding edge cases while truncating the
tool calls and mcp calls.
Today `sub_id` is an ID of a single incoming Codex Op submition. We then
associate all events triggered by this operation using the same
`sub_id`.
At the same time we are also creating a TurnContext per submission and
we'd like to start associating some events (item added/item completed)
with an entire turn instead of just the operation that started it.
Using turn context when sending events give us flexibility to change
notification scheme.
We truncate the output of exec commands to not blow the context window.
However, some cases we weren't doing that. This caused reports of people
with 76% context window left facing `input exceeded context window`
which is weird.
# Tool System Refactor
- Centralizes tool definitions and execution in `core/src/tools/*`:
specs (`spec.rs`), handlers (`handlers/*`), router (`router.rs`),
registry/dispatch (`registry.rs`), and shared context (`context.rs`).
One registry now builds the model-visible tool list and binds handlers.
- Router converts model responses to tool calls; Registry dispatches
with consistent telemetry via `codex-rs/otel` and unified error
handling. Function, Local Shell, MCP, and experimental `unified_exec`
all flow through this path; legacy shell aliases still work.
- Rationale: reduce per‑tool boilerplate, keep spec/handler in sync, and
make adding tools predictable and testable.
Example: `read_file`
- Spec: `core/src/tools/spec.rs` (see `create_read_file_tool`,
registered by `build_specs`).
- Handler: `core/src/tools/handlers/read_file.rs` (absolute `file_path`,
1‑indexed `offset`, `limit`, `L#: ` prefixes, safe truncation).
- E2E test: `core/tests/suite/read_file.rs` validates the tool returns
the requested lines.
## Next steps:
- Decompose `handle_container_exec_with_params`
- Add parallel tool calls