## Summary
- distinguish expired, non-refreshable stored MCP OAuth credentials from
first-time missing credentials
- carry a typed `failureReason: "reauthenticationRequired"` on the
existing `mcpServer/startupStatus/updated` notification only when user
action is required
- keep the public MCP auth-status API unchanged and regenerate the
app-server protocol schemas and documentation
## Why
An MCP server with an expired access token and no usable refresh token
currently fails startup without giving clients a reliable, typed
recovery signal.
The existing startup-status notification is the natural place to carry
this state. Its nullable `failureReason` keeps the recovery reason
attached to the failed startup transition without adding a one-off
notification. Internally, Codex distinguishes first-time login from
reauthentication and emits the reason only when the startup error itself
requires authentication.
## User impact
App clients can prompt an existing user to reconnect an MCP server when
automatic recovery is impossible by handling a failed
`mcpServer/startupStatus/updated` notification whose `failureReason` is
`reauthenticationRequired`. Starting, ready, cancelled, unrelated
failures, and first-time setup carry no reauthentication reason.
## Companion app PR
- openai/openai#1069582
## Validation
- `just test -p codex-app-server-protocol` — 248 passed; schema fixture
tests passed
- `cargo check -p codex-app-server -p codex-tui`
- `just test -p codex-rmcp-client -p codex-mcp` — 184 passed, 2 skipped
- `just test -p codex-protocol -p codex-app-server-protocol -p
codex-mcp` — 579 passed
- `just write-app-server-schema`
- `just fmt`
## Why
#28522 routes selected-plugin HTTP MCP traffic through the owning
executor, but OAuth bootstrap and refresh still used host-local clients.
Executor-only servers therefore cannot complete discovery or login
through the same network boundary as the MCP connection.
## What changed
- adapt `codex_exec_server::HttpClient` to RMCP 1.8's `OAuthHttpClient`
contract
- let RMCP own discovery, dynamic registration, PKCE, token exchange,
and refresh
- route auth status, persisted-token startup, and app-server login
through the server runtime while preserving the existing local discovery
path
- add optional `threadId` to `mcpServer/oauth/login` and echo it in the
completion notification
- implement RMCP's redirect policy and 1 MiB OAuth response limit over
executor HTTP
- cover selected-thread OAuth discovery and login through an
executor-only route
Depends on #28522.
## Why
MCP startup failures from spawned subagents were rendered as global
notifications, so a child thread's failure could pollute the visible
parent transcript. Routing the notification to the child exposed two
related replay problems: session refresh could discard the buffered
event, and a newly created child `ChatWidget` did not know the expected
MCP server set, which could leave its startup spinner running after
every server had settled.
MCP startup diagnostics should remain visible in the thread that owns
the startup without affecting other transcripts. The protocol also needs
to support a future app-scoped MCP lifecycle where startup is not owned
by any thread.
## Reported Behavior
The [originating Slack
report](https://openai.slack.com/archives/C08JZTV654K/p1780604538859939)
called out that using subagents could turn MCP startup failures into a
wall of yellow CLI warnings because repeated failures were not
deduplicated. The intended behavior is for those diagnostics to remain
visible once in the thread that owns the startup, without polluting the
parent transcript.
## What Changed
- add nullable `threadId` ownership to `mcpServer/startupStatus/updated`
- populate it from the app-server conversation ID for the current
thread-scoped lifecycle and regenerate the protocol schema and
TypeScript artifacts
- treat a missing or null `threadId` as app-scoped without injecting it
into the active chat transcript
- route and buffer thread-owned MCP startup notifications by thread in
the TUI
- preserve buffered MCP startup events across child session refresh
- seed expected MCP servers before replaying a thread snapshot so
startup reaches its terminal state
- suppress an identical repeated failure warning for the same server
within one startup round
The owning thread still renders the detailed failure and final `MCP
startup incomplete (...)` summary.
## How to Test
1. Configure an optional MCP server named `smoke` that exits during
initialization.
2. Launch the TUI with multi-agent support enabled.
3. Confirm the main thread's own startup failure renders one detailed
`smoke` warning and one incomplete-startup summary.
4. Spawn exactly one subagent.
5. Confirm the parent transcript does not receive the subagent's MCP
startup failure.
6. Switch to the subagent thread and confirm it contains exactly one
detailed `smoke` failure and one incomplete-startup summary.
7. Confirm the subagent's MCP startup spinner disappears and the thread
remains usable.
8. Switch between the parent and subagent and confirm the warnings
neither move nor duplicate.
Targeted tests:
- `just test -p codex-app-server-protocol`
- `just test -p codex-app-server
thread_start_emits_mcp_server_status_updated_notifications`
- `just test -p codex-tui mcp_startup`
The parent/child behavior and spinner completion were also exercised
manually in tmux. `just argument-comment-lint` was attempted but blocked
by an unrelated local Bazel LLVM empty-glob failure; touched Rust
callsites were inspected manually.
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.
## Summary
`/mcp` in the TUI should reflect the current loaded thread, including
project-local MCP servers from that thread config. Before this change,
`mcpServerStatus/list` only read the latest global MCP config, so the
active chat could miss project-local servers.
This adds optional `threadId` to `mcpServerStatus/list`. When present,
app-server resolves the loaded thread and lists MCP status from the
refreshed effective config for that thread; when omitted, existing
global config behavior stays unchanged.
The TUI now sends the active chat thread id for `/mcp` and `/mcp
verbose`, carries that origin through the async inventory result, and
ignores stale completions if the user has switched threads before the
fetch returns. The app-server schemas were regenerated.
## Follow-up
Once this app-server API change lands, the desktop app should make the
same `threadId` plumbing so its MCP inventory also uses the current
thread config.
Fixes#23874
## Why
`codex-rs/app-server-protocol/src/protocol/v2.rs` had grown into a
single ~12k-line definition file for the entire app-server v2 API.
This is purely a mechanical refactor to break up the monolithic `v2.rs`
file that contains all app-server API v2 types into more modular files,
grouped by resource (e.g. account, thread, turn, etc.).
`just write-app-server-schema` shows no real changes, so we can be sure
that this is purely an internal organizational change.
## What changed
- Replaced the monolithic `protocol/v2.rs` with a `protocol/v2/` module
tree and a small `mod.rs` that only declares and reexports modules.
- Grouped v2 API definitions by conceptual owner, including `account`,
`apps`, `collaboration_mode`, `command_exec`, `config`, `device_key`,
`experimental_feature`, `feedback`, `fs`, `hook`, `item`, `mcp`,
`model`, `notification`, `permissions`, `plugin`, `process`, `realtime`,
`review`, `thread`, `thread_data`, `turn`, and `windows_sandbox`.
- Moved v2 tests into `protocol/v2/tests.rs` so `mod.rs` stays small.
- Kept shared protocol helpers in `protocol/v2/shared.rs`, including the
enum mirroring macro and common cross-resource types.
- Co-located resource-specific notifications and server-request payloads
with the modules that own those resources.
- Regenerated app-server protocol schema fixtures. The schema diffs are
non-semantic newline-only changes after the refactor.
## Verification
- `cargo check -p codex-app-server-protocol`
- `cargo test -p codex-app-server-protocol`
- `just write-app-server-schema`