Files
codex/codex-rs/core-api
starr-openai 5f2543b74e Load configured environments from CODEX_HOME (#20667)
## 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>
2026-05-08 11:17:56 -07:00
..