## Why
Customers need finer-grained control over allowed sandbox modes based on
the host Codex is running on. For example, they may want stricter
sandbox limits on devboxes while keeping a different default elsewhere.
Our current cloud requirements can target user/account groups, but they
cannot vary sandbox requirements by host. That makes remote development
environments awkward because the same top-level `allowed_sandbox_modes`
has to apply everywhere.
## What
Adds a new `remote_sandbox_config` section to `requirements.toml`:
```toml
allowed_sandbox_modes = ["read-only"]
[[remote_sandbox_config]]
hostname_patterns = ["*.org"]
allowed_sandbox_modes = ["read-only", "workspace-write"]
[[remote_sandbox_config]]
hostname_patterns = ["*.sh", "runner-*.ci"]
allowed_sandbox_modes = ["read-only", "danger-full-access"]
```
During requirements resolution, Codex resolves the local host name once,
preferring the machine FQDN when available and falling back to the
cleaned kernel hostname. This host classification is best effort rather
than authenticated device proof.
Each requirements source applies its first matching
`remote_sandbox_config` entry before it is merged with other sources.
The shared merge helper keeps that `apply_remote_sandbox_config` step
paired with requirements merging so new requirements sources do not have
to remember the extra call.
That preserves source precedence: a lower-precedence requirements file
with a matching `remote_sandbox_config` cannot override a
higher-precedence source that already set `allowed_sandbox_modes`.
This also wires the hostname-aware resolution through app-server,
CLI/TUI config loading, config API reads, and config layer metadata so
they all evaluate remote sandbox requirements consistently.
## Verification
- `cargo test -p codex-config remote_sandbox_config`
- `cargo test -p codex-config host_name`
- `cargo test -p codex-core
load_config_layers_applies_matching_remote_sandbox_config`
- `cargo test -p codex-core
system_remote_sandbox_config_keeps_cloud_sandbox_modes`
- `cargo test -p codex-config`
- `cargo test -p codex-core` unit tests passed; `tests/all.rs`
integration matrix was intentionally stopped after the relevant focused
tests passed
- `just fix -p codex-config`
- `just fix -p codex-core`
- `cargo check -p codex-app-server`
## Why
Cloud-hosted sessions need a way for the service that starts or manages
a thread to provide session-owned config without treating all config as
if it came from the same user/project/workspace TOML stack.
The important boundary is ownership: some values should be controlled by
the session/orchestrator, some by the authenticated user, and later some
may come from the executor. The earlier broad config-store shape made
that boundary too fuzzy and overlapped heavily with the existing
filesystem-backed config loader. This PR starts with the smaller piece
we need now: a typed session config loader that can feed the existing
config layer stack while preserving the normal precedence and merge
behavior.
## What Changed
- Added `ThreadConfigLoader` and related typed payloads in
`codex-config`.
- `SessionThreadConfig` currently supports `model_provider`,
`model_providers`, and feature flags.
- `UserThreadConfig` is present as an ownership boundary, but does not
yet add TOML-backed fields.
- `NoopThreadConfigLoader` preserves existing behavior when no external
loader is configured.
- `StaticThreadConfigLoader` supports tests and simple callers.
- Taught thread config sources to produce ordinary `ConfigLayerEntry`
values so the existing `ConfigLayerStack` remains the place where
precedence and merging happen.
- Wired the loader through `ConfigBuilder`, the config loader, and
app-server startup paths so app-server can provide session-owned config
before deriving a thread config.
- Added coverage for:
- translating typed thread config into config layers,
- inserting thread config layers into the stack at the right precedence,
- applying session-provided model provider and feature settings when
app-server derives config from thread params.
## Follow-Ups
This intentionally stops short of adding the remote/service transport.
The next pieces are expected to be:
1. Define the proto/API shape for this interface.
2. Add a client implementation that can source session config from the
service side.
## Verification
- Added unit coverage in `codex-config` for the loader and layer
conversion.
- Added `codex-core` config loader coverage for thread config layer
precedence.
- Added app-server coverage that verifies session thread config wins
over request-provided config for model provider and feature settings.
## Summary
Introduces a single background/control-plane agent task for ChatGPT
backend requests that do not have a thread-scoped task, with
`AuthManager` owning the default ChatGPT backend authorization decision.
Callers now ask `AuthManager` for the default ChatGPT backend
authorization header. `AuthManager` decides whether that is bearer or
background AgentAssertion based on config/internal state, while
low-level bootstrap paths can explicitly request bearer-only auth.
This PR is stacked on PR4 and focuses on the shared background task auth
plumbing plus the first tranche of backend/control-plane consumers. The
remaining callsite wiring is split into PR4.2 to keep review size down.
## Stack
- PR1: https://github.com/openai/codex/pull/17385 - add
`features.use_agent_identity`
- PR2: https://github.com/openai/codex/pull/17386 - register agent
identities when enabled
- PR3: https://github.com/openai/codex/pull/17387 - register agent tasks
when enabled
- PR3.1: https://github.com/openai/codex/pull/17978 - persist and
prewarm registered tasks per thread
- PR4: https://github.com/openai/codex/pull/17980 - use task-scoped
`AgentAssertion` for downstream calls
- PR4.1: this PR - introduce AuthManager-owned background/control-plane
`AgentAssertion` auth
- PR4.2: https://github.com/openai/codex/pull/18260 - use background
task auth for additional backend/control-plane calls
## What Changed
- add background task registration and assertion minting inside
`codex-login`
- persist `agent_identity.background_task_id` separately from
per-session task state
- make `BackgroundAgentTaskManager` private to `codex-login`; call sites
do not instantiate or pass it around
- teach `AuthManager` the ChatGPT backend base URL and feature-derived
background auth mode from resolved config
- expose bearer-only helpers for bootstrap/registration/refresh-style
paths that must not use AgentAssertion
- wire `AuthManager` default ChatGPT authorization through app listing,
connector directory listing, remote plugins, MCP status/listing,
analytics, and core-skills remote calls
- preserve bearer fallback when the feature is disabled, the backend
host is unsupported, or background task registration is not available
## Validation
- `just fmt`
- `cargo check -p codex-core -p codex-login -p codex-analytics -p
codex-app-server -p codex-cloud-requirements -p codex-cloud-tasks -p
codex-models-manager -p codex-chatgpt -p codex-model-provider -p
codex-mcp -p codex-core-skills`
- `cargo test -p codex-login agent_identity`
- `cargo test -p codex-model-provider bearer_auth_provider`
- `cargo test -p codex-core agent_assertion`
- `cargo test -p codex-app-server remote_control`
- `cargo test -p codex-cloud-requirements fetch_cloud_requirements`
- `cargo test -p codex-models-manager manager::tests`
- `cargo test -p codex-chatgpt`
- `cargo test -p codex-cloud-tasks`
- `just fix -p codex-core -p codex-login -p codex-analytics -p
codex-app-server -p codex-cloud-requirements -p codex-cloud-tasks -p
codex-models-manager -p codex-chatgpt -p codex-model-provider -p
codex-mcp -p codex-core-skills`
- `just fix -p codex-app-server`
- `git diff --check`
Abhinav