## Why
The environment-backed exec-server transport currently hardcodes 5
second connect and initialize timeouts in `client_transport.rs`. That is
short for SSH-backed stdio environments and remote websocket
environments, and there is currently no way to raise those values from
`CODEX_HOME/environments.toml`.
This stacked follow-up raises the default environment transport timeouts
and lets each configured environment override them in
`environments.toml`.
## What Changed
- raise the default environment transport connect and initialize
timeouts from 5s to 10s
- store concrete timeout values on `ExecServerTransportParams` instead
of hardcoding them in `connect_for_transport(...)`
- add `connect_timeout_sec` and `initialize_timeout_sec` to
`[[environments]]` entries in `environments.toml`
- apply parse-time defaults so runtime transport code receives fully
resolved timeout values
- reject `connect_timeout_sec` on stdio environments because it only
applies to websocket transports
- extend parser tests to cover the new fields and defaults
## Stack
- base: https://github.com/openai/codex/pull/21794
- this PR: configurable environment transport timeouts
## Validation
- `cd
/Users/starr/code/codex-worktrees/exec-env-timeouts-config-20260508/codex-rs
&& just fmt`
- not run: tests
---------
Co-authored-by: Codex <noreply@openai.com>
## Summary
- make EnvironmentProvider::snapshot path-free and keep providers
focused on provider-owned remote environments
- let provider snapshots request local inclusion via include_local, with
environments.toml including local and CODEX_EXEC_SERVER_URL excluding
local
- move reserved local environment construction into EnvironmentManager
using ExecServerRuntimePaths
Follow-up to https://github.com/openai/codex/pull/20667
## Testing
- just fmt
- git diff --check
- devbox: bazel build --bes_backend= --bes_results_url=
//codex-rs/exec-server:exec-server
- devbox: bazel test --bes_backend= --bes_results_url=
//codex-rs/exec-server:exec-server-unit-tests
Co-authored-by: Codex <noreply@openai.com>
## Why
The earlier PRs add stdio transport support and the config-backed
environment provider, but the feature remains inert until normal Codex
entrypoints construct `EnvironmentManager` with enough context to
discover `CODEX_HOME/environments.toml`. This final stack PR activates
the provider while preserving the legacy `CODEX_EXEC_SERVER_URL`
fallback when no environments file exists.
**Stack position:** this is PR 5 of 5. It is the product wiring PR that
activates the configured environment provider added in PR 4.
## What Changed
- Thread `codex_home` into `EnvironmentManagerArgs`.
- Change `EnvironmentManager::new(...)` to load the provider from
`CODEX_HOME`.
- Preserve legacy behavior by falling back to
`DefaultEnvironmentProvider::from_env()` when `environments.toml` is
absent.
- Make `environments.toml`-backed managers start new threads with all
configured environments, default first, while keeping the legacy env-var
path single-default.
- Update the app-server, TUI, exec, MCP server, connector, prompt-debug,
and thread-manager-sample callsites to pass `codex_home` and handle
provider-loading errors.
## Self-Review Notes
- The multi-environment startup path is intentionally tied to the
`environments.toml` provider. Using `>1` configured environment as the
only signal would also expand the legacy `CODEX_EXEC_SERVER_URL`
provider because it keeps `local` addressable alongside `remote`.
- The startup environment list is still derived inside
`EnvironmentManager`; the provider only says whether its snapshot should
start new threads with all configured environments.
- The thread-manager sample was updated to pass the current
`ThreadManager::new(...)` installation id argument so the stack compiles
under Bazel.
## Stack
- 1. https://github.com/openai/codex/pull/20663 - Add stdio exec-server
listener
- 2. https://github.com/openai/codex/pull/20664 - Add stdio exec-server
client transport
- 3. https://github.com/openai/codex/pull/20665 - Make environment
providers own default selection
- 4. https://github.com/openai/codex/pull/20666 - Add CODEX_HOME
environments TOML provider
- **5. This PR:** https://github.com/openai/codex/pull/20667 - Load
configured environments from CODEX_HOME
Split from original draft: https://github.com/openai/codex/pull/20508
## Validation
- `just fmt`
- `git diff --check`
- `bazel build --config=remote --strategy=remote
--remote_download_toplevel
//codex-rs/thread-manager-sample:codex-thread-manager-sample`
- `bazel test --config=remote --strategy=remote
--remote_download_toplevel
//codex-rs/exec-server:exec-server-unit-tests`
- `bazel test --config=remote --strategy=remote
--remote_download_toplevel --test_sharding_strategy=disabled
--test_arg=default_thread_environment_selections_use_manager_default_id
//codex-rs/core:core-unit-tests`
- `bazel test --config=remote --strategy=remote
--remote_download_toplevel --test_sharding_strategy=disabled
--test_arg=start_thread_uses_all_default_environments_from_codex_home
//codex-rs/core:core-unit-tests`
## Documentation
This activates `CODEX_HOME/environments.toml`; user-facing documentation
should be added before this stack is treated as a documented public
workflow.
---------
Co-authored-by: Codex <noreply@openai.com>
## Why
After stdio transports and provider-owned defaults exist, Codex needs a
config-backed provider that can describe more than the single legacy
`CODEX_EXEC_SERVER_URL` remote. This PR adds that provider without
activating it in product entrypoints yet, keeping parser/validation
review separate from runtime wiring.
**Stack position:** this is PR 4 of 5. It builds on PR 3's
provider/default model and adds the `environments.toml` provider used by
PR 5.
## What Changed
- Add `environment_toml.rs` as the TOML-specific home for parsing,
validation, and provider construction.
- Keep the TOML schema/provider structs private; the public constructor
added here is `EnvironmentManager::from_codex_home(...)`.
- Add `TomlEnvironmentProvider`, including validation for:
- reserved ids such as `local` and `none`
- duplicate ids
- unknown explicit defaults
- empty programs or URLs
- exactly one of `url` or `program` per configured environment
- Support websocket environments with `url = "ws://..."` / `wss://...`.
- Support stdio-command environments with `program = "..."`.
- Add helpers to load `environments.toml` from `CODEX_HOME`, but do not
wire entrypoints to call them yet.
- Add the `toml` dependency for parsing.
## Stack
- 1. https://github.com/openai/codex/pull/20663 - Add stdio exec-server
listener
- 2. https://github.com/openai/codex/pull/20664 - Add stdio exec-server
client transport
- 3. https://github.com/openai/codex/pull/20665 - Make environment
providers own default selection
- **4. This PR:** https://github.com/openai/codex/pull/20666 - Add
CODEX_HOME environments TOML provider
- 5. https://github.com/openai/codex/pull/20667 - Load configured
environments from CODEX_HOME
Split from original draft: https://github.com/openai/codex/pull/20508
## Validation
Not run locally; this was split out of the original draft stack.
## Documentation
This introduces the config shape for `environments.toml`; user-facing
documentation should be added before this stack is treated as a
documented public workflow.
---------
Co-authored-by: Codex <noreply@openai.com>
