## Why App-server needs a way to fetch thread-scoped config from the remote thread config service when the user config opts into that behavior. This mirrors the existing experimental remote thread store endpoint while keeping local/noop behavior as the default. Startup paths also need to avoid silently dropping the remote config endpoint after the first config load. The stdio app-server path discovers the endpoint from the initial config and installs the real thread config loader for later config builds, while in-process clients used by TUI/exec now select the same remote loader directly from their provided config. ## What changed - Added `experimental_thread_config_endpoint` to `ConfigToml`, `Config`, and `core/config.schema.json`. - Added config parsing coverage for the new setting. - Updated app-server startup to select `RemoteThreadConfigLoader` from the initially loaded config, falling back to `NoopThreadConfigLoader` when unset. - Let `ConfigManager` replace its thread config loader after startup discovery so later config loads use the selected loader. - Updated in-process app-server client startup to pass `RemoteThreadConfigLoader` when its config has `experimental_thread_config_endpoint` set. ## Verification - Added `experimental_thread_config_endpoint_loads_from_config_toml`. - Added `runtime_start_args_use_remote_thread_config_loader_when_configured`. - Ran `cargo check -p codex-app-server --lib`. - Ran `cargo test -p codex-app-server-client`.
codex-app-server-client
Shared in-process app-server client used by conversational CLI surfaces:
codex-execcodex-tui
Purpose
This crate centralizes startup and lifecycle management for an in-process
codex-app-server runtime, so CLI clients do not need to duplicate:
- app-server bootstrap and initialize handshake
- in-memory request/event transport wiring
- lifecycle orchestration around caller-provided startup identity
- graceful shutdown behavior
Startup identity
Callers pass both the app-server SessionSource and the initialize
client_info.name explicitly when starting the facade.
That keeps thread metadata (for example in thread/list and thread/read)
aligned with the originating runtime without baking TUI/exec-specific policy
into the shared client layer.
Transport model
The in-process path uses typed channels:
- client -> server:
ClientRequest/ClientNotification - server -> client:
InProcessServerEventServerRequestServerNotificationLegacyNotification
JSON serialization is still used at external transport boundaries (stdio/websocket), but the in-process hot path is typed.
Typed requests still receive app-server responses through the JSON-RPC result envelope internally. That is intentional: the in-process path is meant to preserve app-server semantics while removing the process boundary, not to introduce a second response contract.
Bootstrap behavior
The client facade starts an already-initialized in-process runtime, but thread bootstrap still follows normal app-server flow:
- caller sends
thread/startorthread/resume - app-server returns the immediate typed response
- richer session metadata may arrive later as a
SessionConfiguredlegacy event
Surfaces such as TUI and exec may therefore need a short bootstrap phase where they reconcile startup response data with later events.
Backpressure and shutdown
- Queues are bounded and use
DEFAULT_IN_PROCESS_CHANNEL_CAPACITYby default. - Full queues return explicit overload behavior instead of unbounded growth.
shutdown()performs a bounded graceful shutdown and then aborts if timeout is exceeded.
If the client falls behind on event consumption, the worker emits
InProcessServerEvent::Lagged and may reject pending server requests so
approval flows do not hang indefinitely behind a saturated queue.