## Why
Extension-owned HTTP MCP servers previously inherited the default protocol mode. Extensions need to select a mode for their own server independently of other HTTP servers.
## What changed
- Add `McpServerContribution::SetWithProtocolMode` and re-export `McpProtocolMode` through the extension API.
- Carry the winning registration's protocol override through catalog resolution and materialization, and apply it to Streamable HTTP connections.
- Preserve existing defaults when no override is present. Selecting a protocol mode does not grant host-owned Apps cache access or environment authority.
## Testing
Add coverage for registration precedence and materialization, and extend cache isolation tests to cover explicit protocol selection. Add an integration test verifying that extension servers can select either the legacy or newer protocol while other HTTP servers retain the default mode.
GitOrigin-RevId: 606cecc03094a93258ffc433849f575020b81473
## What changed
- Add a positive `output_token_limit` setting to each entry under an MCP server's `tools` configuration.
- Apply the most restrictive limit when plugin and user policies overlap, while keeping approval policy independent.
- Carry the effective MCP output budget in conversation history so tool output, post-tool hook responses, and resumed sessions use the same truncation limit.
## Testing
- Cover configuration parsing, serialization, schema validation, and plugin policy merging.
- Cover MCP output below and above the configured limit, post-tool hook responses, and session resume.
GitOrigin-RevId: d0beb4fca9ba6055d9e1d31c137373b465d50d61
## Why
Selected executor plugin roots could still expose capabilities when managed
requirements disabled the `plugins` feature.
## What changed
- Suppress MCP servers, skills, apps, and connectors from selected executor
plugins when `plugins` is disabled, while preserving the selected-root
identity used to filter those capabilities.
- Apply the policy consistently to direct selected-root discovery and batched
executor capability discovery.
## Testing
- Add contributor-level and app-server coverage that verifies disabled plugin
capabilities are absent and their MCP servers never start.
GitOrigin-RevId: e30bd8a936c4b0e083908b89a65f4d02e01747de
## What changed
- Add environment-provided MCP restrictions for configured and plugin-provided servers.
- Disable attachment-scoped servers while their environment configuration is pending, failed, or unselected, while preserving selected-plugin access and the controller-owned Apps server.
- Apply the resolved policy to runtime startup, model tool exposure, telemetry, OAuth flows, and skill dependency installation.
## Testing
- Cover policy filtering for configured and plugin servers, environment state transitions, Apps ownership, and managed OAuth rejection.
GitOrigin-RevId: 7ca5d4dda14068e758497f88835d5cba685e159e
## What changed
- Carry selected plugin identities from MCP discovery into per-turn extension data, limited to capability roots that are ready for the turn.
- Annotate executor skill catalog entries with the matching plugin ID and `user` scope.
- Include that attribution in `skill_invocation` analytics for both explicit and implicit executor skill invocations.
## Testing
- Extend the executor skills app-server test to verify plugin ID, skill scope, and invocation type for explicit and implicit analytics events.
GitOrigin-RevId: 9345600ae29bcb8eb894fffd2d6f7b05f22ebf74
## What changed
- Resolve MCP server policy directly from the effective user configuration for selected executor-plugin roots.
- Apply server enablement, tool allow/deny lists, and default and per-tool approval modes while preserving stricter plugin-declared restrictions.
- Cover policy merging and opaque selected-root IDs in the executor-plugin MCP integration tests.
GitOrigin-RevId: dce3021969ba71e642de52312449cab6277515c3
## Why
Executor capability discovery can traverse plugin and skill roots, including
symlinks. Under restricted filesystem permissions, discovery must not expose
files outside the permitted paths.
## What changed
- Pass each environment's filesystem sandbox context through capability root
discovery and apply it to metadata, directory walks, and file reads.
- Enable discovery for restricted sessions so permitted executor skills remain
available while inaccessible roots and symlink targets are omitted.
- Key discovery caches by sandbox context and reject sandboxed discovery on
executors that do not advertise support for it.
- Split requests with more than 128 roots into supported-size batches.
## Testing
- Cover permitted and denied external symlink targets.
- Verify restricted skill listing excludes inaccessible skills.
- Verify cache separation across permission contexts and discovery of 129 roots.
GitOrigin-RevId: 44d16468ca003403bdb8b71a04ae8c9ff94ed494
## Why
Selected capability roots can contribute plugins, MCP servers, connectors, and
skills. Discovering each contribution separately requires repeated access to the
executor filesystem.
## What changed
- Add the `capabilityRoots/discoverV1` exec-server RPC to scan selected roots and
materialize recognized plugin manifests, configuration files, skill
instructions, and skill metadata in one bounded request.
- Add the opt-in `executor_capability_discovery` feature, with a thread-scoped
cache and per-step snapshot shared by MCP and skill discovery.
- Parse MCP, connector, and skill contributions from the materialized snapshot,
including serving cached skill instructions without another filesystem read.
## Testing
- Cover discovery limits, manifest precedence, root-local failures, cache reuse,
plugin contributions, and parity with the existing environment skill loader.
GitOrigin-RevId: f98fd2321cafb58c596db02da1f83c09d8eb375d
## What changed
- Let deferred environments provide selected capability roots with their ready signal.
- Validate that those roots have unique, non-empty IDs, belong to the registering environment, and stay within the root limit.
- Include roots from ready turn environments when resolving MCP contributions, and refresh the MCP runtime when the selected root set changes.
- Expose the exact ready root set to MCP contributors so executor plugins become available with their environment.
## Testing
- Cover ready-root propagation, validation failures, replacement isolation, reconnection, and MCP plugin availability refresh.
GitOrigin-RevId: ec3498aab1164824025094e96a9b1063b7b731ad
## Summary
- Forward Codexs canonical `originator` header on ChatGPT-hosted Apps
and plugin-runtime MCP requests.
- Preserve the configured `X-OpenAI-Product-Sku` header.
- Cover originator-only and originator-plus-SKU configurations.
## Why
Sites project creation is logged downstream of Apps MCP. Production
validation found `CODEX_UNKNOWN_DEFAULT` project-created threads that
matched `codex_surface=desktop_app` and `originator=Codex Desktop` in
`fact_codex_cli`
([query](https://kepler.gateway.data-1.internal.api.openai.org/permalink/H_mVoVPqLQ0)).
The hosted Apps MCP configuration forwarded the product SKU but not
Codexs canonical originator, so codex-backend could not derive
`CODEX_DESKTOP_APP` for those tool calls.
## Validation
- `just fmt`
- `CARGO_HOME=/private/tmp/codex-cargo-home
CARGO_TARGET_DIR=/private/tmp/codex-target just test -p codex-mcp` (106
passed)
- `CARGO_HOME=/private/tmp/codex-cargo-home
CARGO_TARGET_DIR=/private/tmp/codex-target just fix -p codex-mcp`
## Why
Generic plugin guidance is currently emitted only with initial context
from host plugin state. An executor-selected plugin can become available
later in the same turn, making its skills and tools usable without ever
telling the model how plugin capabilities should be used.
## What
- project every ready selected plugin package, including skill-only
plugins
- carry plugin availability with the exact MCP runtime projection while
preserving MCP manager reuse when servers and connectors are unchanged
- move generic plugin guidance from the static initial-context path into
persisted World State
- recognize legacy and retained plugin fragments so resume and
compaction do not duplicate guidance
## Testing
- `just test -p codex-mcp-extension`
- `just test -p codex-core plugins_instructions`
- `just test -p codex-core
plugin_availability_change_reuses_the_mcp_manager`
- `just test -p codex-app-server --test all selected_capabilit`
## Why
Selected plugin metadata is stable, but MCP processes are live runtime
state. They need different lifetimes:
- the MCP extension caches manifest, MCP, and connector declarations for
each stable selected root;
- each model step projects that cached metadata through the roots that
resolved as ready for that exact step;
- the MCP manager is rebuilt only when that availability projection
changes.
This matches executor skills: both features consume the same resolved
step roots instead of inferring readiness from the turn's selected
environments.
## Behavior
```text
E1 not ready for this step
-> no E1 MCP servers or connectors
-> cached plugin metadata stays in ext/mcp
E1 becomes ready
-> reuse cached metadata
-> publish one MCP runtime containing E1 capabilities
same ready roots on the next step
-> reuse the exact runtime; no rediscovery and no MCP restart
resume
-> create new extension thread state and a new MCP runtime
```
All model-facing consumers use the same step snapshot:
```text
resolved selected roots
|
v
extension MCP/connector projection
|
v
{ MCP config, connector snapshot, MCP manager }
|
+-> advertise model tools
+-> build app/connector tools
+-> execute MCP calls
```
## Cache contract
The existing MCP extension owns a cache keyed by the full
`SelectedCapabilityRoot`:
```rust
let state = thread_store.get_or_init(SelectedExecutorPluginMcpState::default);
```
The cache lives with extension thread state. Environment availability
filters projection but does not invalidate metadata. Resume creates new
thread state. There is no file watcher or executor generation because
contents behind a stable environment/root are assumed stable.
## What changes
- Keeps executor plugin discovery and cached metadata in `ext/mcp`.
- Caches MCP and connector declarations together per selected root.
- Uses the step's already-resolved capability roots, including lazy
environments that are not turn environments.
- Reuses the current MCP runtime when the ready-root projection is
unchanged.
- Uses the same step MCP manager and connector snapshot for
model-visible tools and execution.
- Resolves direct thread-scoped MCP requests from the current
selected-root projection.
## Deliberately out of scope
- `app/list` remains based on the latest global host-plugin state; this
PR does not make its response or notifications thread-specific.
- `required = true` startup semantics do not apply to delayed executor
MCP activation.
- No filesystem/content invalidation.
- No transport-disconnect watcher.
- No executor generations or environment replacement semantics.
- No client sharing across complete manager replacements.
## Stack
1. Extension-owned World State sections.
2. Project executor skills through World State.
3. Pin one MCP runtime to each model step.
4. **This PR:** project selected MCP and connector state from
extension-owned metadata.
5. Integration coverage for selected capability availability and resume.
## Verification
-
`selected_plugin_servers_use_managed_requirements_for_the_selected_root_id`
- The stacked integration PR covers unavailable to ready activation,
unchanged-runtime reuse, skills, MCP tools, connector attribution, and
cold resume.
## Why
Selected capability roots belong to the executor filesystem, not the
app-server host. Converting their path strings into the host's native
`Path` breaks whenever the two machines use different path conventions,
such as a Windows executor behind a Unix app-server.
This PR establishes `PathUri` as the selected-plugin boundary so the
executor remains authoritative for its paths.
## What changed
- Require `selectedCapabilityRoots[].location.path` to be a canonical
`file:` URI and deserialize it directly as `PathUri`; native path
strings are rejected.
- Update the app-server schema, generated TypeScript, examples, and
request coverage for the URI contract.
- Keep selected roots, resolved plugin locations, manifest paths, and
manifest resources as `PathUri`.
- Inspect and read plugin roots and manifests only through the selected
environment's `ExecutorFileSystem`.
- Parse executor manifests with the shared URI-native parser from #29620
instead of projecting them onto the host filesystem.
- Enforce resource containment lexically and preserve the root URI's
POSIX or Windows path convention.
- Cover foreign Windows plugin roots and URI-native manifest resources.
```text
thread/start
selectedCapabilityRoots[].location.path = "file:///C:/plugins/demo"
| PathUri
v
ExecutorFileSystem
|
+--> plugin.json
+--> manifest resources
```
This PR stops at the shared selected-plugin representation. The next two
PRs remove the remaining host-path projections in the skill and MCP
consumers.
## Stack
1. #29614 — add lexical `PathUri` containment.
2. #29620 — share URI-native manifest path resolution.
3. **This PR** — keep selected plugin roots and resources URI-native.
4. #29626 — load executor skills without host path conversion.
5. #29628 — resolve executor MCP working directories without host path
conversion.
## Why
**In short:** this PR discovers MCP registrations by reading a selected
plugin's `.mcp.json` on its executor. #27884 then resolves those
registrations in the shared catalog.
`thread/start.selectedCapabilityRoots` can select a plugin root owned by
an executor, and Codex can resolve that package through the executor
filesystem. MCP declarations inside the selected plugin are still
ignored.
This PR adds the source-specific discovery layer on top of the
selected-plugin catalog boundary in #27884:
```text
selected capability root
|
v
resolve the plugin through its executor filesystem
|
v
read and normalize its MCP config through the same filesystem
|
v
contribute stdio registrations bound to that environment ID
```
The existing MCP launcher and connection manager remain unchanged. MCP
config parsing is shared with local plugins through #27863.
## What changed
- Added an executor plugin MCP provider in the MCP extension.
- Retained only the exact filesystem capability used for package
resolution and reused it for the selected plugin's MCP config, with no
host-filesystem fallback or unrelated process/HTTP authority.
- Read either the manifest-declared MCP config or the default
`.mcp.json`; a missing default file means the plugin has no MCP servers.
- Accepted stdio servers only for this first vertical. Executor-owned
HTTP declarations are skipped with a warning until their placement
semantics are defined.
- Normalized stdio registrations with the owning environment's stable
logical ID and plugin-root working directory.
- Resolved environment-variable names on the owning executor and
rejected explicit local forwarding for non-local plugins.
- Froze discovered declarations once per active thread runtime, then
applied current managed plugin and MCP requirements when contributing
them.
- Carried the selected root ID, display name, and selection order into
the catalog contribution defined by #27884.
## Behavior and scope
There is intentionally no production behavior change yet. This PR
provides the executor provider and contribution boundary, but app-server
does not install it in this change. Existing local plugin MCP loading is
unchanged, and no MCP process is launched by this PR alone.
## Assumptions
- The selected root ID is the plugin policy identity; the manifest
display name is presentation metadata.
- An environment ID is a stable logical authority. Reconnection or
replacement under the same ID does not change ownership.
- Selected plugin packages and their manifests are trusted inputs.
- The selected package and MCP discovery snapshot remain frozen for the
active thread runtime.
## Follow-up
The next PR installs this contributor in app-server and adds an
end-to-end test proving that a selected plugin MCP tool launches on its
owning executor, can be called by the model, survives an explicit MCP
refresh, and is invisible when its root was not selected.
Resume, fork, environment removal or ID changes, dynamic catalog reload,
and executor-owned HTTP MCP placement remain separate lifecycle
decisions.
## Verification
Focused tests cover executor-only filesystem reads, missing and
malformed config, stdio filtering and normalization, managed
requirements, package attribution, and selection order. CI owns
execution of the test suite.
