## Why
Executor-owned plugin roots are `PathUri`, but MCP config normalization
still converts them into a native `Path` using the app-server host's
rules. Relative `cwd` values can therefore resolve against the wrong
filesystem when host and executor path conventions differ.
This PR keeps executor MCP paths URI-native until the selected
environment launches the server, while retaining the existing host
parser behavior.
## What changed
- Keep one shared MCP normalization path with narrow host-`Path` and
executor-`PathUri` entrypoints.
- Preserve native host resolution for locally installed plugin MCP
configs.
- For executor configs, default `cwd` to the plugin root and resolve
relative working directories with the root URI's path convention.
- Accept explicit executor `file:` URIs only when they remain within the
selected plugin root.
- Preserve the selected environment id and existing remote
environment-variable ownership rules.
- Route the executor plugin provider through the URI-native entrypoint
without converting the root on the host.
- Ensure `codex doctor` does not probe executor-owned stdio commands or
foreign working directories on the host.
- Cover foreign Windows roots, relative and absolute executor working
directories, traversal rejection, runtime resolution, and doctor
behavior.
```text
plugin root: file:///C:/plugins/demo
configured cwd: scripts
|
v
resolved cwd: file:///C:/plugins/demo/scripts
|
v
launch through the selected executor
```
No new provider or filesystem abstraction is introduced.
## Stack
1. #29614 — add lexical `PathUri` containment.
2. #29620 — share URI-native manifest path resolution.
3. #28918 — keep selected plugin roots and resources URI-native.
4. #29626 — load executor skills without host path conversion.
5. **This PR** — resolve executor MCP working directories without host
path conversion.
## Summary
- add trace-level instrumentation around per-server MCP setup, client
construction, initialization, and initial tool listing
- trace Codex Apps tool and server-info cache loads
- attach `server_name` to server-scoped spans so slow startup work can
be attributed to a specific MCP server
## Why
`session_init.mcp_manager_init` can occasionally be slow, but its
existing coarse span does not identify whether time is spent loading the
Codex Apps cache, constructing a client, initializing a transport, or
listing tools. These definition-level spans provide that breakdown
without changing startup behavior.
## Validation
- `just test -p codex-mcp` (87 passed)
- `just test -p codex-rmcp-client` (86 passed, 2 skipped)
## Summary
- replace the stale `AskForApproval::OnFailure` reference in the MCP
connection manager test with `AskForApproval::OnRequest`
- restore `codex-mcp` test compilation after `OnFailure` was removed in
#28418
## Root cause
The test was added on main after the approval-policy removal branch had
already updated the other references, so the newly added call site was
missed when #28418 merged.
## Validation
- `just test -p codex-mcp` (90 passed)
- `just fmt`
## Summary
MCP refresh replaced the published connection manager without shutting
down the manager it superseded. If another task retained that old
manager, its stdio MCP processes stayed alive and accumulated across
refreshes.
Atomically swap in the refreshed manager, then explicitly shut down the
exact manager returned by the swap. Add a process-level regression test
that retains the old manager during refresh and verifies its stdio
process exits while the replacement remains available.
## Context
Explicit cleanup was lost when manager publication moved to `ArcSwap`.
Dropping the old manager is not a reliable shutdown boundary because
active callers can retain its `Arc` and underlying client process
handles.
## Summary
- Update `rmcp` and `rmcp-macros` from 1.7.0 to 1.8.0.
- Adapt to the new shared `peer_info` return type.
- Box OAuth status discovery at the MCP boundary to keep the expanded
future type from overflowing Rust's trait recursion limit.
This brings in custom OAuth HTTP client support from
[modelcontextprotocol/rust-sdk#908](https://github.com/modelcontextprotocol/rust-sdk/pull/908).
## Summary
- Require the reserved Codex Apps MCP server name to be present in the
connection manager before treating it as host-owned.
- Update auth elicitation tests to model an installed host-owned Codex
Apps server without sending startup events to the test session.
## Why
PR #29518 replaced the old host-owned flag with a name-only check. That
made non-host-owned tests with the reserved codex_apps name enter auth
elicitation and wait forever for a response.
## Summary
- let `codex sandbox` accept the JSON value from
`codex/sandbox-state-meta`
- require the payload `permissionProfile` instead of falling back to
ambient permissions
- reuse the existing macOS, Linux, and Windows launch paths, treating
external sandbox state conservatively as read-only
- let opaque forwarders add runtime read roots and disable direct
network access without decoding the payload
Builds on #29113, which is now on `main`.
## Tests
- `just test -p codex-cli debug_sandbox::tests`
- `cargo build -p codex-rmcp-client --bin test_stdio_server`
- `just test -p codex-core
stdio_mcp_tool_call_includes_sandbox_state_meta`
- `just test -p codex-mcp`
- `just fmt`
## Why
`McpConnectionManager::new` classified the Codex Apps server twice: once
to create its tools cache context and again to select its runtime
authentication provider. Keeping those decisions separate makes it
harder to see that they belong to the same server-specific setup path.
## What changed
- Group Codex Apps cache and authentication setup under one explicit
branch.
- Keep regular MCP server setup in the corresponding `else` branch.
- Limit environment bearer-token inspection to the Codex Apps path where
it affects runtime authentication.
## Why
Codex Apps cache writes are already restricted to Codex Apps call paths:
startup invokes the helper only from the Codex Apps branch, and hard
refresh operates on the reserved Codex Apps server directly. Rechecking
the server name inside the cache helper duplicates that classification
and leaves the helper with an argument that cannot change valid
behavior.
## What changed
- Remove the redundant server-name check and parameter from the cache
writer.
- Rename the helper to `write_codex_apps_tools_cache` to reflect its
narrower contract.
- Update production and test callsites to use the simplified API.
## Why
Codex Apps-specific behavior is currently distributed across cache
helpers, startup, tool conversion, and model-visible annotation. Each
layer independently checks the reserved server name, which obscures the
boundary between trusted host-owned connector metadata and regular MCP
server data.
Classifying the server once when `AsyncManagedClient` is created gives
the client a single source of truth and makes the two processing paths
explicit.
## What changed
- Record whether an `AsyncManagedClient` represents the Codex Apps
server at construction time.
- Route startup cache loading, cache persistence, and cache telemetry
through the Codex Apps branch.
- Split uncached tool conversion between Codex Apps normalization and
regular MCP metadata sanitization.
- Split model-visible schema and plugin provenance handling along the
same boundary.
- Remove redundant server-name guards from helpers that are now called
only from the Codex Apps branch.
## Verification
- Preserve behavioral coverage that verifies Codex Apps connector
metadata and the complete converted `ToolInfo` shape.
## Stack
Depends on #29518.
## Why
Codex Apps server admission is already decided before
`McpConnectionManager` is constructed. `effective_mcp_servers` and
`effective_mcp_servers_from_configured` remove the server when the apps
feature or required authentication is unavailable, so storing the same
decision on the manager duplicates state that can drift from the
effective server map.
## What changed
- Remove `host_owned_codex_apps_enabled` from `McpConnectionManager` and
its constructor.
- Identify the host-owned Codex Apps server by its reserved server name
once it is present in the effective server map.
- Remove the now-unused flag calculations and constructor arguments from
production and test callsites.
## Why
Remote stdio MCP servers can run in an environment whose path convention
differs from the Codex host. A Windows cwd such as
`C:\Users\openai\share` is absolute for the executor but was rejected by
a POSIX orchestrator.
Built on #29501, now merged, which only clarifies the host-native
`PathUri` constructor name.
## What changed
- Deserialize MCP cwd values as `LegacyAppPathString` so config does not
apply host path rules.
- Interpret that spelling as host-native for local launches and convert
it to `PathUri` at executor launch.
- Skip host filesystem and command resolution checks for remote stdio in
`codex doctor`.
- Add host-independent config and executor-boundary coverage using the
foreign path convention for each test platform.
## Validation
- `just test -p codex-utils-path-uri -p codex-config -p codex-mcp -p
codex-rmcp-client` (408 passed)
- `just test -p codex-cli -p codex-rmcp-client` (372 passed)
- `cargo check --workspace --tests`
- `just test` (11,311 passed; 43 unrelated environment/timing failures)
- `just fix -p codex-cli -p codex-config -p codex-core -p codex-mcp -p
codex-mcp-extension -p codex-rmcp-client -p codex-tui`
## Why
Orchestrator-provided skills and Codex Apps MCP tools add model-visible
instructions, resources, and tools beyond the local workspace. Hosts
need config-level switches to disable those orchestrator-owned surfaces
independently, without disabling regular skills or regular MCP servers.
## What changed
- Adds `[orchestrator.skills].enabled` and `[orchestrator.mcp].enabled`
config entries, both defaulting to `true`.
- Includes the new settings in `config.schema.json` and in the config
lock so resolved thread configuration preserves the same orchestrator
exposure decisions.
- Threads `orchestrator.skills.enabled` through the app-server skills
extension so disabled orchestrator skills do not expose the `skills`
namespace or inject orchestrator skill context.
- Gates Codex Apps MCP exposure, app instructions, and app auth
eligibility on `orchestrator.mcp.enabled` while leaving non-Codex-Apps
MCP tools available.
- Updates the thread-manager sample config to disable both
orchestrator-owned surfaces.
## Verification
- Added config parsing, loading, defaulting, and schema coverage for the
new settings.
- Added MCP exposure coverage that `orchestrator.mcp.enabled = false`
removes Codex Apps tools while preserving regular MCP tools.
- Added app-server coverage that `orchestrator.skills.enabled = false`
prevents orchestrator skill tools, prompts, and resource reads from
reaching the model turn.
## Summary
- remove the duplicated originator-specific connector ID denylists
- stop filtering connector directory/accessibility results and
live/cached Codex Apps MCP tools by hardcoded connector ID
- remove the now-unused `codex-login` dependency from
`codex-utils-plugins`
- update regression coverage so formerly blocked connector IDs are
preserved
## Why
The client-side policy was duplicated across crates, used opaque IDs
without ownership or expiry information, and could drift between app
listing and MCP tool behavior. Server-provided visibility,
authorization, plugin discoverability, accessibility, enabled-state
handling, and consequential-tool approval templates remain unchanged.
## Validation
- `just fmt`
- `just bazel-lock-update`
- `just bazel-lock-check`
- `git diff --check`
- confirmed the final diff contains no hardcoded denylist symbols
A targeted `codex-mcp` test build spent an unusually long time in local
compilation/linking. Its first attempt exposed a test-only `PartialEq`
assertion issue, which was corrected. A follow-up non-linking `cargo
check -p codex-mcp --tests` was still running when this draft was
opened; CI should provide the complete Rust validation.
Scope MCP sandbox metadata to the MCP server's owning environment.
Previously, `codex/sandbox-state-meta` always used the turn's primary
cwd and rebuilt a legacy sandbox policy from that cwd. That can be wrong
for MCP servers owned by a different execution environment.
This now sends the owning environment cwd as a `file:` URI in
`sandboxCwd`, keeps `permissionProfile` as the permission source of
truth, and omits sandbox-state metadata when a non-default server
environment is not selected for the turn. Local/default MCP servers keep
the existing fallback cwd behavior.
Tests:
- `just fmt`
- `just bazel-lock-update`
- `just bazel-lock-check`
- `just test -p codex-mcp`
- `just test -p codex-core mcp_sandbox_cwd`
- `cargo build -p codex-rmcp-client --bin test_stdio_server`
- `just test -p codex-core
stdio_mcp_tool_call_includes_sandbox_state_meta`
## Why
Hosted orchestrator skills are read through the remote MCP resource
server. Within one thread, the same catalog or skill resource can be
requested multiple times by prompt injection and the `skills.list` /
`skills.read` tools. Re-fetching adds latency and can make those
surfaces observe different remote contents during the same thread.
This is a follow-up to #28333: orchestrator skills remain limited to
threads without a local executor, and those threads now get a stable
per-thread view of the remote skill data they use.
## What changed
- Reuse the existing per-thread orchestrator catalog snapshot for
`skills.list` and `skills.read` availability checks.
- Cache successful orchestrator resource reads by authority, package,
and resource so prompt injection and tool calls share the same contents.
- Keep the cache memory-only and bounded to 100 resources and 8 MiB per
thread.
- Leave host and executor skill reads unchanged, and do not cache failed
remote reads.
## Verification
- Extended the app-server MCP resource integration test to read the same
hosted skill resource twice and verify that the remote server receives
one read.
- The same test verifies that catalog discovery and the selected skill's
main prompt are each fetched only once per thread.
## Why
**In short:** this PR resolves already-discovered MCP registrations. It
does not read selected plugins or discover their MCP servers.
The resolved MCP catalog currently builds config and auto-discovered
plugin registrations before runtime contributors are applied. A
thread-selected plugin needs a distinct precedence tier in that same
initial resolution pass: otherwise a disabled lower-precedence winner
can leave stale name-level state behind, and the winning MCP tools
cannot be attributed to the selected package reliably.
This PR adds that catalog boundary before executor discovery is
connected.
## What changed
- Added an explicit selected-plugin registration tier between
auto-discovered plugins and explicit config.
- Collected selected-plugin contributions before the initial catalog
build, while leaving compatibility and generic extension overlays in
their existing runtime phase.
- Retained the winning plugin ID and display name directly on
plugin-owned catalog registrations.
- Derived MCP tool provenance from the winning catalog entry instead of
joining against local-only plugin summaries.
- Retained the winning selected server's tool approval policy in the
running connection manager, so a selected registration cannot inherit
approval behavior from a losing local plugin.
- Kept remembered approval session-scoped for selected plugins until
there is an authority-aware persistence contract; Codex will not write
approval back to an unrelated local plugin.
- Preserved existing name-level disabled vetoes for discovered plugins
and config, while keeping a selected package's own disabled registration
scoped to that registration.
- Preserved deterministic selection order and existing config,
compatibility, and extension precedence.
The resulting order is:
```text
auto-discovered plugin
< selected plugin
< explicit config
< compatibility registration
< extension overlay
```
## Behavior and scope
This is a catalog and provenance change only. No production host
contributes selected-plugin MCP registrations yet, so existing local MCP
behavior remains unchanged.
The stacked follow-up, #27870, installs the executor plugin provider
that produces these registrations. App-server activation remains a
separate final step.
## Verification
Focused tests cover precedence, deterministic selected-plugin conflicts,
disabled-veto behavior across catalog phases, managed requirements
before selected-plugin resolution, winning-server approval policy, and
attribution when local and selected packages share an ID or server name.
CI owns execution of the test suite.
## Summary
- store MCP OAuth credentials in the configured auth credential backend
- support encrypted-local OAuth storage, including legacy keyring
migration
- propagate the credential backend through MCP refresh, session, CLI,
and app-server paths
## Stack
1. #27504 — config and feature flag
2. #27535 — auth-specific secret namespaces
3. #27539 — encrypted CLI auth storage
4. this PR — encrypted MCP OAuth storage
This is a parallel review stack; the original #17931 remains unchanged.
## Tests
- `just test -p codex-rmcp-client` (the transport round-trip test passed
after building the required `codex` binary and retrying)
- `just test -p codex-mcp`
- `just test -p codex-app-server
refresh_config_uses_latest_auth_keyring_backend`
- `just test -p codex-core
refresh_mcp_servers_is_deferred_until_next_turn`
- `just test -p codex-cli mcp`
- `just fix -p codex-rmcp-client -p codex-mcp -p codex-core -p codex-cli
-p codex-app-server -p codex-protocol`
- `just bazel-lock-check`
## Why
We want a thread-selected plugin to eventually expose stdio MCP servers
that run on the executor owning that plugin.
The existing plugin MCP parser lived inside `core-plugins` and was
coupled to the host filesystem loader. Reusing it from an executor
provider would either duplicate MCP normalization or make the plugin
package layer own MCP runtime semantics. This PR creates the shared
MCP-owned boundary first.
In simple terms:
```text
plugin .mcp.json
|
v
shared parser in codex-mcp
|
+-- Declared placement: preserve current local-plugin behavior
|
+-- Environment placement: produce config bound to one executor
```
This builds on the authority-bound plugin descriptors from #27692. It
intentionally does not discover, register, or launch executor MCP
servers yet.
## What changed
- Moved plugin MCP file parsing and normalization from `core-plugins`
into `codex-mcp`.
- Kept support for both existing file shapes: a top-level server map and
an object containing `mcpServers`.
- Kept per-server failure isolation: one invalid server does not discard
valid siblings, while malformed top-level JSON still fails the whole
file.
- Updated the existing local plugin loader to use `Declared` placement,
preserving its current transport, OAuth, relative `cwd`, and error
behavior.
- Added `Environment` placement for the next stacked PR:
- the selected environment ID overrides anything declared by the plugin;
- missing stdio `cwd` defaults to the plugin root;
- relative `cwd` is resolved beneath the plugin root and cannot traverse
outside it;
- bare or source-less environment-variable references resolve on a
non-local executor;
- explicit orchestrator environment-variable forwarding is rejected for
executor-owned plugins.
## User impact
None in this PR. Existing local plugin MCP loading follows the same
behavior through the shared parser. The executor placement mode is not
connected to thread startup until the follow-up registration PR.
## Assumptions
- A selected capability root's environment is authoritative. A plugin
cannot redirect its stdio process to the orchestrator or another
executor.
- Relative working directories belong under the plugin package root.
Explicit absolute working directories remain valid within the owning
environment.
- For a non-local executor, unqualified environment-variable names refer
to that executor. Reading an orchestrator variable requires an explicit
contract and is rejected for now.
- Parsing only produces normalized `McpServerConfig` values. Process
startup remains owned by the existing MCP runtime and connection
manager.
## Follow-ups
1. Add the executor MCP provider and catalog registration: read the
selected plugin's MCP config through the same executor filesystem,
support stdio only, freeze the result per active thread, apply managed
policy, and resolve name collisions as discovered plugin < selected
plugin < explicit config.
2. Install that provider in app-server and add an end-to-end test
proving `thread/start.selectedCapabilityRoots` launches and calls the
MCP tool on the selected executor, preserves the frozen registration
across refresh, and does not expose it to an unselected thread.
3. After the initial executor-stdio vertical, define
resume/fork/environment-replacement semantics, executor HTTP placement,
warning delivery, common MCP tool-context bounds, and move remaining MCP
source composition above core.
## Verification
- `cargo check -p codex-mcp -p codex-core-plugins --tests`
- `just bazel-lock-check`
- Added focused parser coverage for legacy local normalization, executor
authority, working-directory handling, and environment-variable
sourcing.
## Why
MCP servers currently come from user config, local plugins,
compatibility Apps synthesis, and host extensions. Those sources were
composed by mutating a shared map, leaving registration identity,
precedence, removal, and provenance implicit in assembly order.
Before adding executor-owned MCPs, Codex needs one durable resolution
boundary above `McpConnectionManager`. This PR introduces that boundary
while preserving current server configuration, policy, and runtime
behavior. Executor-scoped registrations and explicit policy layers
remain follow-ups.
## What changed
- Add typed `McpServerRegistration` inputs and an immutable
`ResolvedMcpCatalog` in `codex-mcp`.
- Retain each registration's complete `McpServerConfig`, including its
environment binding, while recording its source and provenance.
- Preserve the existing structural precedence between plugin, config,
compatibility, and ordered extension sources.
- Resolve equal-precedence actions by contribution order; provenance IDs
are used only for diagnostics and cannot affect the winner.
- Preserve extension removals and the existing name-scoped `enabled =
false` veto.
- Report same-tier conflicts with every contender and the final catalog
outcome, including whether the winning action registers or removes the
server.
- Require MCP contributors to provide a stable diagnostic identity.
- Derive materialized server maps and plugin ownership from the resolved
catalog.
`McpConnectionManager`, transport startup, tool calls, and resource
routing continue to consume the same effective `McpServerConfig` values.
## Scope
This PR does not add new MCP capabilities or change user-visible
behavior. It does not add executor plugin discovery, thread-scoped
registrations, dynamic refresh generations, or new user/managed policy
semantics.
## Verification
- Added focused catalog coverage for source precedence, complete
configuration preservation, disabled vetoes, plugin ownership,
contribution-order tie breaking, removal outcomes, and conflict
diagnostics.
- Extended hosted Apps coverage for ordered extension removal and
Apps-disabled hosts with and without the hosted extension installed.
- `cargo check -p codex-mcp --tests -p codex-extension-api -p
codex-core`
## Why
#27198 made the extension-owned `codex_apps` MCP connection the hosted
plugin runtime, but its `mcp/skill` resources still bypassed the skills
extension. App-server could list and read those resources through
generic MCP APIs, but a thread with no selected environment did not
expose them in the model's skills catalog or load their `SKILL.md`
through `$skill`.
Hosted skills should stay remote while using the same typed catalog,
source authority, deduplication, bounded contextual catalog, and
selected-skill prompt injection as host and executor skills. They should
not be downloaded or exposed as ambient filesystem paths.
## What changed
- Add a session-scoped `McpResourceClient` over the replaceable MCP
connection manager so resource list/read calls follow startup and
refresh replacements.
- Add a `BackendSkillProvider` that pages `codex_apps` resources,
accepts bounded and validated `mcp/skill` entries, and reads a selected
skill's `SKILL.md` through the same MCP connection.
- Register the remote provider in app-server and include it in the
skills catalog even when a thread has no selected capability roots or
executor.
- Contribute hosted skill metadata through the bounded
`AvailableSkillsInstructions` developer-context path, exclude remote
entries from per-turn catalog injection, and classify `<skills>`
messages as contextual developer content so rollback can trim and
rebuild them correctly.
## Testing
- Extend the app-server MCP resource integration test with
`environments: []` to exercise two-page discovery, filter a
non-`mcp/skill` resource, verify the escaped developer catalog entry and
user-role `<skill>` fragment containing the fetched `SKILL.md`, and
preserve generic MCP resource reads.
- Add core event-mapping coverage that classifies `<skills>` developer
messages as contextual history.
## Summary
We originally addressed startup prewarming holding the read side of
`RwLock<McpConnectionManager>` by snapshotting tool-list state. Review
feedback identified the broader ownership problem: the outer
synchronization should only publish or retrieve the current manager,
while MCP operations rely on the manager's internal synchronization. A
follow-up preserved operation retirement with a separate gate, but
further review questioned whether that synchronization was actually
required and whether we could support latest-wins replacement instead.
This PR now stores the current MCP manager in `ArcSwap`. Each operation
uses `load_full()` to obtain an owned `Arc<McpConnectionManager>`, then
performs MCP I/O without retaining the publication mechanism. Refresh
cancels obsolete startup work, constructs a replacement, and atomically
publishes it. New operations see the latest manager, while operations
that already loaded the previous manager retain a valid handle. Refresh
happens at a turn boundary, so there should be no active user tool calls
to drain.
Git history supports dropping the outer `RwLock`. It was introduced in
`03ffe4d595` on November 17, 2025 for non-blocking MCP startup: the
session published an empty manager, startup initialized that same object
while holding the write lock, and readers waited for initialization.
`7cd2e84026` on February 19, 2026 removed that two-phase initialization
in favor of constructing a fresh manager and swapping it in, explicitly
noting that `Option` or `OnceCell` could replace the placeholder design.
Hot reload later reused the existing lock to publish a replacement, but
I found no indication that the lock was introduced to guarantee
in-flight tool calls finish before refresh or shutdown.
Terminal shutdown remains separate from refresh: it aborts startup
prewarming and active tasks before shutting down the current manager, so
tool calls may be interrupted and no model WebSocket work continues
after shutdown. Focused regression coverage exercises pending tool-list
cancellation, deferred refresh, and startup-prewarm shutdown.
## Stack
- Base: #27191
- This PR is the third vertical and should be reviewed against
`jif/external-plugins-2`, not `main`.
## Why
#27191 moves the host-owned Apps MCP registration behind an extension
contributor, but deliberately preserves the existing endpoint-selection
feature while that contribution contract lands. App-server can therefore
resolve the server through extensions, yet the hosted plugin endpoint is
still selected through temporary `apps_mcp_path_override` plumbing.
That is not the long-term plugin model. A plugin can bundle skills,
connectors, MCP servers, and hooks, and those components do not all need
the same source or execution environment. In particular, an
authenticated HTTP MCP server can expose plugin capabilities directly
from a backend without an executor or an orchestrator filesystem.
This PR completes that hosted vertical. App-server's MCP extension now
owns the aggregate hosted plugin runtime at `/ps/mcp`. Connector actions
continue to arrive as MCP tools, while backend-provided skills arrive as
MCP resources and use Codex's existing resource list/read paths. No
second backend client, skill filesystem, or generic plugin activation
framework is introduced.
The backend route remains the hosted implementation. This change
replaces Codex's temporary endpoint-selection mechanism, not the service
behind the endpoint.
## What changed
### Hosted plugin runtime
The MCP extension now contributes `codex_apps` as the hosted plugin
runtime rather than as a configurable Apps endpoint:
- `https://chatgpt.com` resolves to
`https://chatgpt.com/backend-api/ps/mcp`;
- a bare custom ChatGPT base resolves to `/api/codex/ps/mcp`;
- the existing product-SKU header and ChatGPT authentication behavior
are preserved;
- executor availability is never consulted for this streamable HTTP
transport.
The same MCP connection carries both component shapes supported by the
hosted endpoint:
- connector actions are discovered and invoked as MCP tools;
- hosted skills are enumerated and read as MCP resources through the
existing `list_mcp_resources` and `read_mcp_resource` paths.
This keeps component access in the subsystem that already owns the
protocol instead of downloading backend skills into an orchestrator
filesystem or inventing a parallel hosted-skill client.
### Explicit runtime ordering
`McpManager` now resolves the reserved `codex_apps` entry in three
ordered phases:
1. install the legacy Apps fallback for compatibility;
2. apply ordered extension `Set` or `Remove` overlays;
3. apply the final ChatGPT-auth gate without synthesizing the server
again.
This ordering is important:
- an ordinary configured or plugin MCP server cannot claim the
auth-bearing `codex_apps` name;
- an extension-contributed hosted runtime wins over the fallback;
- an extension `Remove` remains authoritative;
- a host without the MCP extension retains the legacy Apps endpoint and
current local-only behavior.
The temporary `legacy_apps_mcp_loader_enabled` coordination flag is no
longer needed.
### Remove the path override
The `apps_mcp_path_override` feature and its runtime plumbing are
removed, including:
- the feature registry entry and structured feature config;
- `Config` and `McpConfig` fields;
- config schema output;
- config-lock materialization;
- URL override handling in `codex-mcp`.
Existing boolean and structured forms still deserialize as ignored
compatibility input. They are omitted from new serialized config, and
config-lock comparison normalizes the removed input so older locks
remain replayable.
### App-server coverage
App-server MCP fixtures now serve the hosted route at
`/api/codex/ps/mcp`. Existing resource-read and tool/elicitation flows
therefore exercise the extension-owned endpoint rather than succeeding
through the legacy fallback.
The stack also adds the missing `codex_chatgpt::connectors` re-export
for the manager-backed connector helper introduced in #27191.
## Compatibility
- App-server installs the extension and uses `/ps/mcp` for the hosted
runtime.
- CLI and other hosts that do not install the extension retain the
legacy Apps endpoint.
- Apps disabled or non-ChatGPT authentication removes `codex_apps` from
the effective runtime view.
- Existing local plugins, local skills, executor-selected skills,
configured MCP servers, and MCP OAuth behavior are otherwise unchanged.
- Backend plugin enablement remains account/workspace state owned by the
hosted endpoint; this PR does not add thread-local backend plugin
selection.
## Architectural fit
The stack now proves two independent runtime shapes:
1. #27184 resolves filesystem-backed skills through the executor that
owns a selected root.
2. #27191 and this PR resolve a backend-hosted HTTP MCP through an
extension with no executor.
Together they preserve the intended separation:
- selection identifies a plugin/root when explicit selection is needed;
- each component's owning extension resolves its concrete access
mechanism;
- execution stays with the runtime required by that component;
- existing skills, MCP, connector, and hook subsystems remain the
downstream consumers.
## Planned follow-ups
1. **Executor stdio MCP:** selecting an executor plugin registers a
manifest-declared stdio MCP server and executes it in the environment
that owns the plugin.
2. **Optional backend selection:** only if CCA needs thread-local
selection distinct from backend account/workspace enablement, add a
concrete backend-owned capability location and surface those selected
skills through the skills catalog.
3. **Connector metadata and hooks:** activate those plugin components
through their existing owning subsystems, with executor hooks remaining
environment-bound.
4. **Propagation and persistence:** define explicit resume, fork,
subagent, refresh, and environment-removal semantics once selected roots
have multiple real consumers.
5. **Local convergence:** migrate legacy local skill, MCP, connector,
and hook paths behind their owning extensions one vertical at a time,
then remove duplicate core managers and compatibility plumbing after
parity.
## Verification
Coverage in this change exercises:
- extension-owned `/backend-api/ps/mcp` registration without an
executor;
- preservation of the legacy endpoint in hosts without the extension;
- extension `Set` and `Remove` precedence over the legacy fallback;
- ChatGPT-auth gating for the reserved server;
- hosted MCP resource reads with and without an active thread;
- connector tool invocation and MCP elicitation through the hosted
route;
- ignored boolean and structured forms of the removed path override;
- config-lock replay compatibility for the removed feature.
`cargo check -p codex-features -p codex-mcp-extension -p
codex-app-server` passes. Tests and Clippy were not run locally under
the current development instruction; CI provides the full validation
pass.
## Why
Required MCP server startup was enforced in `Session::new` after
`McpConnectionManager` had already created the clients. That split let
other manager construction paths bypass the same requirement and exposed
manager internals solely so the session could validate them. Keeping
required-server readiness in the constructor gives every caller one
consistent startup contract.
## What changed
- make `McpConnectionManager::new` return `anyhow::Result<Self>` and
fail when an enabled, required server cannot initialize
- pass the startup cancellation token into the constructor so
required-server waits remain cancellable
- propagate constructor failures through resource reads, connector
discovery, and MCP status collection
- preserve the active manager and cancellation token when a refreshed
replacement fails
- keep required-startup failure collection private and cover the
constructor error contract directly
## Validation
- updated the focused connection-manager test to assert the complete
required-server startup error
- local tests not run; relying on CI
## Summary
- order `McpConnectionManager` methods by visibility, with the primary
constructor and public API first
- restrict `list_available_server_infos` to `codex-mcp`
- make `new_uninitialized` a private test-only helper
## Why
The manager exposed methods that are only used inside `codex-mcp` or its
unit tests. Tightening those methods keeps the exported API intentional,
while the new ordering makes the supported surface easier to scan.
## Validation
- `just fmt`
- `git diff --check`
- local tests not run; relying on CI
## Stack
- Base: #27184
- This PR is the second vertical and should be reviewed against
`jif/external-plugins-1`, not `main`.
## Why
CCA is moving toward a split runtime where the orchestrator may have no
filesystem or executor, but it still needs to activate remotely hosted
plugin components. HTTP MCP servers are the simplest complete example:
they need configuration and host authentication, but they do not need an
executor process.
The Apps MCP endpoint is currently synthesized by a special-purpose
loader inside the MCP runtime. That works locally, but it leaves hosted
MCP activation outside the extension model being established in #27184.
It also makes the Apps path a poor foundation for plugins whose skills,
MCP servers, connectors, and hooks may come from different sources or
execute in different places.
This PR moves that one behavior behind an extension-owned contribution
while preserving the existing local fallback. It deliberately does not
introduce a generic plugin activation framework.
## What changed
### MCP extension contribution
`codex-extension-api` gains an ordered `McpServerContributor` contract.
A contributor returns typed `Set` or `Remove` overlays for MCP server
configuration; later contributors win for the names they own.
The contract stays at the existing MCP configuration boundary.
Extensions do not create a second connection manager or transport
abstraction.
### Hosted Apps MCP extension
A new `codex-mcp-extension` contributes the reserved `codex_apps` server
from the existing Apps feature, ChatGPT base URL, path override, and
product SKU configuration.
When `apps_mcp_path_override` is enabled for `https://chatgpt.com`, the
resulting streamable HTTP endpoint is
`https://chatgpt.com/backend-api/ps/mcp`. The existing ChatGPT-auth gate
remains authoritative, so this server can run in an orchestrator-only
process without being exposed for API-key sessions.
### One resolved runtime view
`McpManager` now distinguishes three views:
- **configured:** config- and plugin-backed servers before extension
overlays;
- **runtime:** configured servers plus host-installed extension
contributions;
- **effective:** runtime servers after auth gating and compatibility
built-ins.
App-server installs the hosted MCP extension and uses the runtime view
for thread startup, refresh, status, threadless resource reads,
connector discovery, and MCP OAuth lookup. This keeps
`mcpServer/oauth/login` consistent with the servers exposed by the other
MCP APIs. The hosted Apps server itself continues to use existing
ChatGPT host authentication rather than MCP OAuth.
## Compatibility
Hosts that do not install the MCP extension retain the existing Apps MCP
synthesis path. This preserves current local-only, CLI, and
standalone-host behavior while app-server exercises the extension path.
Disabling Apps removes the reserved `codex_apps` entry, and losing
ChatGPT auth removes it from the effective runtime view. Executor
availability is not consulted for this HTTP transport.
## Follow-ups
The next vertical will resolve a manifest-declared stdio MCP server from
an executor-selected plugin root and execute it in the environment that
owns that root. Later verticals can add backend-owned skills, connector
metadata, hooks, durable selection semantics, and incremental local
convergence without changing the component-specific runtime boundaries
introduced here.
## Verification
Focused coverage was added for:
- contributing the hosted Apps MCP at `/backend-api/ps/mcp` without an
executor;
- requiring ChatGPT auth in the effective runtime view;
- removing a reserved configured Apps server when the Apps feature is
disabled.
`cargo check -p codex-app-server -p codex-mcp-extension -p
codex-extension-api -p codex-mcp` passed. Tests and Clippy were not run
locally under the current development instruction; CI provides the full
validation pass.
WIll make it easier to uprev when the new draft spec is supported.
Also updates reqwest where needed for compatibility but doesn't update
it everywhere since this is already a large diff.
The new version of rmcp handles certain kinds of authentication failures
differently, this patch includes support for identifying the failing scope
in a WWW-Authenticate header.
## Why
When a turn needs a follow-up request after tool output is recorded,
Codex can still appear stuck in `Thinking` before the next `/responses`
request is opened. The existing local trace showed the last completed
response and the absence of a new backend request, but it did not show
whether the stall was in tool-router preparation or later request setup.
Issue: N/A (internal incident investigation)
## What Changed
Added trace spans around the pre-stream tool-router handoff in
`core/src/session/turn.rs`, including the `built_tools` phase and the
MCP manager read lock.
Added per-server MCP tool-listing spans and trace breadcrumbs in
`codex-mcp/src/connection_manager.rs` with startup snapshot /
startup-complete state so a pending MCP client is visible in feedback
logs instead of looking like a silent hang.
## Verification
- `just fmt`
- `just test -p codex-mcp`
- `just test -p codex-core` (prior full rerun fails in this workspace on
unrelated integration tests: code-mode output length expectations, one
shell timeout formatting assertion, and shell snapshot timeouts; latest
review-fix rerun compiled and passed 1160 tests before I stopped the
abnormally slow unrelated suite)
## Why
The `non_prefixed_mcp_tool_names` feature should be applied where MCP
tools become model-visible, not by remapping names later in core.
Keeping the decision in `McpConnectionManager` construction makes
`ToolInfo` the single shaped view that spec building, deferred tool
search, routing, and unavailable-tool placeholders can consume directly.
This also preserves the existing external behavior while the feature is
off, and keeps the feature-on behavior for code mode and hooks explicit
at the manager boundary.
## What Changed
- Add `McpToolNameMode` to `codex-mcp` and flow it through `McpConfig`
into `McpConnectionManager::new`.
- Normalize MCP `ToolInfo` names in the manager using either
legacy-prefixed namespaces or non-prefixed namespaces; the legacy path
adds `mcp__` without restoring the old trailing namespace suffix.
- Remove the core-side MCP name remapping path so specs, tool search,
session resolution, and unavailable-tool placeholder construction use
the manager-provided `ToolName` values directly.
- Keep code mode flattening on the `__` namespace separator.
- Preserve hook compatibility by giving non-prefixed MCP hook names
legacy `mcp__...` matcher aliases.
- Add/adjust integration and unit coverage for non-prefixed code-mode
behavior, hook matching with the feature on and off, and manager-level
legacy prefixing.
## Testing
- `cargo test -p codex-mcp --lib`
- `cargo test -p codex-core --lib tools::spec::tests -- --nocapture`
- `cargo test -p codex-core --lib mcp_tools -- --nocapture`
- `cargo test -p codex-core --lib mcp_tool_exposure -- --nocapture`
- `cargo test -p codex-core --test all mcp_tool -- --nocapture`
- `cargo test -p codex-core --test all search_tool -- --nocapture`
- `cargo test -p codex-core --test all hooks_mcp -- --nocapture`
- `cargo test -p codex-core --test all
code_mode_uses_non_prefixed_mcp_tool_names_when_feature_enabled --
--nocapture`
- `cargo test -p codex-tools`
- `cargo test -p codex-features`
## Summary
- route each configured MCP server through an explicit per-server
`environment_id` instead of a manager-wide remote toggle
- default omitted `environment_id` to `local`, resolve named ids through
`EnvironmentManager`, and fail only the affected MCP server when an
explicit id is unknown
- keep local stdio on the existing local launcher path for now, while
named-environment stdio uses the selected environment backend and
requires an absolute `cwd`
- allow local HTTP MCP servers to keep using the ambient HTTP client
when no local `Environment` is configured; named-environment HTTP MCPs
use that environment's HTTP client
## Validation
- devbox Bazel build: `bazel build --bes_backend= --bes_results_url=
//codex-rs/cli:codex //codex-rs/rmcp-client:test_stdio_server
//codex-rs/rmcp-client:test_streamable_http_server`
- devbox app-server config matrix with real `config.toml` /
`environments.toml` files covering omitted local, explicit local,
omitted local under remote default, explicit remote stdio, local HTTP
without local env, explicit remote HTTP, local stdio without local env,
unknown explicit env, and remote stdio without `cwd`
Adding the id of the plugin that contains the MCP (if any) so we can
apply filters at plugin level.
## Summary
- carry the plugin owner into MCP runtime provenance
- attach `plugin_id` to outbound plugin-backed MCP tool-call `_meta`
- avoid misattributing user-configured MCP servers that shadow plugin
server names
## Testing
- `just fmt`
- `just fix -p codex-mcp`
- `just fix -p codex-core`
- `cargo test -p codex-mcp`
- `cargo test -p codex-core
plugin_mcp_tool_call_request_meta_includes_plugin_id`
- `cargo test -p codex-core
to_mcp_config_omits_plugin_id_when_user_server_shadows_plugin_mcp`
- `cargo test -p codex-core
rebuild_preserving_session_layers_refreshes_plugin_derived_mcp_config`
- `git diff --check`
## Notes
- Attempted `cargo test -p codex-core`; it aborted in
`agent::control::tests::resume_agent_from_rollout_skips_descendants_when_parent_resume_fails`
with a stack overflow before the full suite completed.
This adds `apps_mcp_product_sku` as a toplevel config.toml key. We pass
the given value as a header when listing MCPs for the client, allowing
connectors to be filtered per product entry point.
---------
Co-authored-by: Codex <noreply@openai.com>
## Why
This PR is the invariant-cleanup layer that follows the workspace-roots
base merged in [#22610](https://github.com/openai/codex/pull/22610).
#22610 adds `[permissions.<id>.workspace_roots]` and keeps runtime
workspace roots separate from the raw permission profile, but its
in-memory representation is intentionally transitional: `Permissions`
still carries the selected profile identity next to a constrained
`PermissionProfile`. That makes APIs such as
`set_constrained_permission_profile_with_active_profile()` fragile
because the id and value only mean the right thing when every caller
keeps them in sync.
This PR introduces a single resolved profile state so profile identity,
`extends`, the profile value, and profile-declared workspace roots
travel together. The next PR,
[#22611](https://github.com/openai/codex/pull/22611), builds on this by
changing the app-server turn API to select permission profiles by id
plus runtime workspace roots.
## Stack Context
- #22610, now merged: adds profile-declared `workspace_roots`, runtime
workspace roots, and `:workspace_roots` materialization.
- This PR: replaces the parallel active-profile/profile-value fields
with `PermissionProfileState`.
- #22611: switches app-server turn updates toward profile ids plus
runtime workspace roots.
- #22612: updates TUI/exec summaries to show the effective workspace
roots.
Keeping this separate from #22611 is deliberate: reviewers can validate
the internal state invariant before reviewing the app-server protocol
migration.
## What Changed
- Added `ResolvedPermissionProfile::{Legacy, BuiltIn, Named}` and
`PermissionProfileState`.
- Typed built-in profile ids with `BuiltInPermissionProfileId`.
- Moved selected profile identity and profile-declared workspace roots
into the resolved state.
- Replaced `Permissions` parallel profile fields with one
`permission_profile_state`.
- Removed `set_constrained_permission_profile_with_active_profile()`
from session sync paths.
- Kept trusted session replay/`SessionConfigured` compatibility through
explicit session snapshot helpers.
- Updated session configuration, MCP initialization, app-server, exec,
TUI, and guardian call sites to consume `&PermissionProfile` directly.
## Review Guide
Start with `codex-rs/core/src/config/resolved_permission_profile.rs`; it
is the new invariant boundary. Then review
`codex-rs/core/src/config/mod.rs` to see how config loading records
active profile identity and profile workspace roots. The remaining
call-site changes are mostly mechanical fallout from
`Permissions::permission_profile()` returning `&PermissionProfile`
instead of `&Constrained<PermissionProfile>`.
## Verification
The existing config/session coverage now constructs and asserts through
`PermissionProfileState`. The workspace-root config test also asserts
that profile-declared roots are preserved in the resolved state, which
is the behavior #22611 relies on when runtime roots become mutable
through the app-server API.
---
[//]: # (BEGIN SAPLING FOOTER)
Stack created with [Sapling](https://sapling-scm.com). Best reviewed
with [ReviewStack](https://reviewstack.dev/openai/codex/pull/22683).
* #22612
* #22611
* __->__ #22683
## Why
Some MCP OAuth providers require a pre-registered public client ID and
cannot rely on dynamic client registration. Codex already supports MCP
OAuth, but it had no way to supply that client ID from config into the
PKCE flow.
## What changed
- add `oauth.client_id` under `[mcp_servers.<server>]` config, including
config editing and schema generation
- thread the configured client ID through CLI, app-server, plugin login,
and MCP skill dependency OAuth entrypoints
- configure RMCP authorization with the explicit client when present,
while preserving the existing dynamic-registration path when it is
absent
- add focused coverage for config parsing/serialization and OAuth URL
generation
## Verification
- `cargo test -p codex-config -p codex-rmcp-client -p codex-mcp -p
codex-core-plugins`
- `cargo test -p codex-core blocking_replace_mcp_servers_round_trips
--lib`
- `cargo test -p codex-core
replace_mcp_servers_streamable_http_serializes_oauth_resource --lib`
- `cargo test -p codex-core config_schema_matches_fixture --lib`
## Notes
Broader local package runs still hit unrelated pre-existing stack
overflows in:
- `codex-app-server::in_process_start_clamps_zero_channel_capacity`
-
`codex-core::resume_agent_from_rollout_uses_edge_data_when_descendant_metadata_source_is_stale`
Remove unnecessary prefix filtering from codex
## Test Plan
Test local cli build + make sure backend returns appropriate apps
```
cd ~/code/codex/codex-rs
cargo build -p codex-cli --bin codex
./target/debug/codex
```
Appropriate apps show up in my list
## 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
We've added support for auth elicitation behind the auth_elicitation
flag, but servers need to explicitly check the capability before it
decides to send elicitations in order to be backward compatible. This PR
adds the capability advertising conditioned on the flag.
## What changed
- Build `client_elicitation_capability` from the `AuthElicitation`
feature state.
- Thread that capability through MCP config, session startup, and
`McpConnectionManager` so RMCP initialization advertises the correct
elicitation support.
- Advertise both `form` and `url` elicitation when the feature is
enabled, and preserve the empty default capability when it is disabled.
- Add coverage for the feature-derived config shape and the advertised
initialization payload.
## Testing
- `cargo test -p codex-mcp`
- `cargo test -p codex-core
to_mcp_config_preserves_auth_elicitation_feature_from_config`
- `cargo test -p codex-core` *(currently fails outside this change in
`tools::handlers::multi_agents::tests::tool_handlers_cascade_close_and_resume_and_keep_explicitly_closed_subtrees_closed`
with a stack overflow after unrelated tests have started running)*
## 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`
## Summary
`cargo test` has entails both running standard Rust tests and doctests.
It turns out that the doctest discovery is fairly slow, and it's a cost
you pay even for crates that don't include any doctests.
This PR disables doctests with `doctest = false` for crates that lack
any doctests.
For the collection of crates below, this speeds up test execution by
>4x.
E.g., before this PR:
```
Benchmark 1: cargo test -p codex-utils-absolute-path -p codex-utils-cache -p codex-utils-cli -p codex-utils-home-dir -p codex-utils-output-truncation -p codex-utils-path -p codex-utils-string -p codex-utils-template -p codex-utils-elapsed -p codex-utils-json-to-toml
Time (mean ± σ): 1.849 s ± 4.455 s [User: 0.752 s, System: 1.367 s]
Range (min … max): 0.418 s … 14.529 s 10 runs
```
And after:
```
Benchmark 1: cargo test -p codex-utils-absolute-path -p codex-utils-cache -p codex-utils-cli -p codex-utils-home-dir -p codex-utils-output-truncation -p codex-utils-path -p codex-utils-string -p codex-utils-template -p codex-utils-elapsed -p codex-utils-json-to-toml
Time (mean ± σ): 428.6 ms ± 6.9 ms [User: 187.7 ms, System: 219.7 ms]
Range (min … max): 418.0 ms … 436.8 ms 10 runs
```
For a single crate, with >2x speedup, before:
```
Benchmark 1: cargo test -p codex-utils-string
Time (mean ± σ): 491.1 ms ± 9.0 ms [User: 229.8 ms, System: 234.9 ms]
Range (min … max): 480.9 ms … 512.0 ms 10 runs
```
And after:
```
Benchmark 1: cargo test -p codex-utils-string
Time (mean ± σ): 213.9 ms ± 4.3 ms [User: 112.8 ms, System: 84.0 ms]
Range (min … max): 206.8 ms … 221.0 ms 13 runs
```
Co-authored-by: Codex <noreply@openai.com>
## Summary
This PR removes the synthetic `HashMap<String, ToolInfo>` keys from MCP
tool discovery. `McpConnectionManager::list_all_tools()` now returns
normalized `Vec<ToolInfo>`, and downstream code derives identity from
`ToolInfo::canonical_tool_name()`.
The motivation is to keep model-visible tool identity on
`ToolName`/`ToolInfo` instead of parallel string map keys, so future
namespace changes do not have to preserve otherwise-unused lookup keys.
## Changes
- Rename the MCP normalization path from `qualify_tools` to
`normalize_tools_for_model` and return tool values directly.
- Flow MCP tool lists through connectors, plugin injection, router/spec
building, code mode, and tool search as vectors/slices.
- Keep direct/deferred subtraction local to `mcp_tool_exposure`, using
`ToolName` values.
- Update tests to compare `ToolName` instances where MCP identity
matters.
## Validation
- `cargo test -p codex-mcp test_normalize_tools`
- `cargo test -p codex-core mcp_tool_exposure`
- `cargo test -p codex-core
direct_mcp_tools_register_namespaced_handlers`
- `cargo test -p codex-core
search_tool_registers_namespaced_mcp_tool_aliases`
- `just fix -p codex-mcp`
- `just fix -p codex-core`
## 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>
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