## Why
Generic Apps guidance is emitted only while building static initial
context. If the Apps MCP is unavailable then and recovers later in the
same turn, its tools can become usable without the model receiving the
guidance for using them.
## What
- move generic Apps guidance into a persisted `apps_instructions` World
State section
- derive availability from the request's MCP runtime while preserving
the existing feature, auth, orchestrator-MCP, and config gates
- recognize legacy and retained Apps fragments so resume and compaction
do not duplicate guidance
- register Apps guidance as rollback-trimmable context
- remove the old static injection path and its now-unused connector
helper
- keep tool construction on its existing independent `list_all_tools()`
read rather than adding a request-wide cache; a reconnect between the
two reads can differ for one request and reconciles on the next request
Apps and plugin guidance now render after the remaining static
host-skills block, with Apps before Plugins.
## Testing
- `just fmt`
- `just test -p codex-core apps_instructions`
- `just test -p codex-core
apps_guidance_appears_after_background_recovery_within_a_turn`
- `just test -p codex-core
drop_last_n_user_turns_trims_context_updates_above_rolled_back_turn`
## Summary
- Add `iconAssets` and `iconDarkAssets` to the app-list protocol.
- Preserve structured icons through directory merging and the connector,
app-
server, and TUI boundaries.
- Keep legacy logo URLs unchanged as compatibility fallbacks.
- Update generated protocol schemas and TypeScript types.
## Why
Connector metadata is consumed by connector discovery, ChatGPT
integration, core, and TUI code. Treating app-server's wire DTO as the
shared domain model reverses the intended dependency direction.
## What changed
- Added connector-owned app branding, review, screenshot, metadata, and
info types.
- Added explicit conversions in app-server and TUI while preserving
app-server's wire payloads.
- Removed production app-server-protocol dependencies from connectors
and ChatGPT connector code.
## Stack
This is PR 4 of 6, stacked on [PR
#29722](https://github.com/openai/codex/pull/29722). Review only the
delta from `codex/split-config-layer-types`. Next: [PR
#29724](https://github.com/openai/codex/pull/29724).
## Validation
- Connector and tools coverage passed.
- App-server app-list coverage passed: 13 tests.
## 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
## Why
`codex-mcp` already owns the shared MCP API surface, including `auth`,
`McpConfig`, `CODEX_APPS_MCP_SERVER_NAME`, and tool-name helpers in
[`codex-rs/codex-mcp/src/mcp/mod.rs`](f61e85dbfb/codex-rs/codex-mcp/src/mcp/mod.rs (L1-L35)).
Re-exporting that surface from `codex_core::mcp` gives downstream crates
two import paths for the same API and hides the real crate dependency.
This PR keeps `codex_core::mcp` focused on the local `McpManager`
wrapper in
[`codex-rs/core/src/mcp.rs`](f61e85dbfb/codex-rs/core/src/mcp.rs (L13-L40))
and makes consumers import shared MCP APIs from `codex_mcp` directly.
## What
- Remove the `codex_mcp::mcp` re-export surface from `core/src/mcp.rs`.
- Update `codex-core` internals plus `codex-app-server`, `codex-cli`,
and `codex-tui` test code to import MCP APIs from `codex_mcp::mcp`
directly.
- Add explicit `codex-mcp` dependencies where those crates now use that
API surface, and refresh `Cargo.lock`.
## Verification
- `just bazel-lock-check`
- `cargo test -p codex-core -p codex-cli -p codex-tui`
- `codex-cli` passed.
- `codex-core` still fails five unrelated config tests in
`core/src/config/config_tests.rs` (`approvals_reviewer_*` and
`smart_approvals_alias_*`).
- A broader `cargo test -p codex-core -p codex-app-server -p codex-cli
-p codex-tui` run previously hung in `codex-app-server` test
`in_process_start_uses_requested_session_source_for_thread_start`.
Move the general `Apps`, `Skills` and `Plugins` instructions blocks out
of `user_instructions` and into the developer message, with new `Apps ->
Skills -> Plugins` order for better clarity.
Also wrap those sections in stable XML-style instruction tags (like
other sections) and update prompt-layout tests/snapshots. This makes the
tests less brittle in snapshot output (we can parse the sections), and
it consolidates the capability instructions in one place.
#### Tests
Updated snapshots, added tests.
`<AGENTS_MD>` disappearing in snapshots is expected: before this change,
the wrapped user-instructions message was kept alive by `Skills`
content. Now that `Skills` and `Plugins` are in the developer message,
that wrapper only appears when there is real
project-doc/user-instructions content.
---------
Co-authored-by: Charley Cunningham <ccunningham@openai.com>
- clarify app mentions are in user messages
- clarify what it means for tools to be provided via `codex_apps` MCP
- add plugin descriptions (with basic sanitization) to top-level `##
Plugins` section alongside the corresponding plugin names
- explain that skills from plugins are prefixed with `plugin_name:` in
top-level `##Plugins` section
changes to more logically organize `Apps`, `Skills`, and `Plugins`
instructions will be in a separate PR, as that shuffles dev + user
instructions in ways that change tests broadly.
### Tests
confirmed in local rollout, some new tests.
