split Windows auth keyring storage

## Summary
- add an exec-server `envPolicy` field; when present, the server starts
from its own process env and applies the shell environment policy there
- keep `env` as the exact environment for local/embedded starts, but
make it an overlay for remote unified-exec starts
- move the shell-environment-policy builder into `codex-config` so Core
and exec-server share the inherit/filter/set/include behavior
- overlay only runtime/sandbox/network deltas from Core onto the
exec-server-derived env

## Why
Remote unified exec was materializing the shell env inside Core and
forwarding the whole map to exec-server, so remote processes could
inherit the orchestrator machine's `HOME`, `PATH`, etc. This keeps the
base env on the executor while preserving Core-owned runtime additions
like `CODEX_THREAD_ID`, unified-exec defaults, network proxy env, and
sandbox marker env.

## Validation
- `just fmt`
- `git diff --check`
- `cargo test -p codex-exec-server --lib`
- `cargo test -p codex-core --lib unified_exec::process_manager::tests`
- `cargo test -p codex-core --lib exec_env::tests`
- `cargo test -p codex-core --lib exec_env_tests` (compile-only; filter
matched 0 tests)
- `cargo test -p codex-config --lib shell_environment` (compile-only;
filter matched 0 tests)
- `just bazel-lock-update`

## Known local validation issue
- `just bazel-lock-check` is not runnable in this checkout: it invokes
`./scripts/check-module-bazel-lock.sh`, which is missing.

---------

Co-authored-by: Codex <noreply@openai.com>
Co-authored-by: pakrym-oai <pakrym@openai.com>

codex-rs/Cargo.lock

@@ -2098,6 +2098,7 @@ dependencies = [
  "async-trait",
  "base64 0.22.1",
  "codex-app-server-protocol",
+ "codex-config",
  "codex-protocol",
  "codex-sandboxing",
  "codex-utils-absolute-path",
@@ -2107,6 +2108,7 @@ dependencies = [
  "pretty_assertions",
  "serde",
  "serde_json",
+ "serial_test",
  "tempfile",
  "test-case",
  "thiserror 2.0.18",

codex-rs/config/src/lib.rs

@@ -14,6 +14,7 @@ pub mod profile_toml;
 mod project_root_markers;
 mod requirements_exec_policy;
 pub mod schema;
+pub mod shell_environment;
 mod skills_config;
 mod state;
 pub mod types;

codex-rs/config/src/shell_environment.rs

@@ -0,0 +1,123 @@
+use crate::types::EnvironmentVariablePattern;
+use crate::types::ShellEnvironmentPolicy;
+use crate::types::ShellEnvironmentPolicyInherit;
+use std::collections::HashMap;
+use std::collections::HashSet;
+
+pub const CODEX_THREAD_ID_ENV_VAR: &str = "CODEX_THREAD_ID";
+
+/// Construct a shell environment from the supplied process environment and
+/// shell-environment policy.
+pub fn create_env(
+    policy: &ShellEnvironmentPolicy,
+    thread_id: Option<&str>,
+) -> HashMap<String, String> {
+    create_env_from_vars(std::env::vars(), policy, thread_id)
+}
+
+pub fn create_env_from_vars<I>(
+    vars: I,
+    policy: &ShellEnvironmentPolicy,
+    thread_id: Option<&str>,
+) -> HashMap<String, String>
+where
+    I: IntoIterator<Item = (String, String)>,
+{
+    let mut env_map = populate_env(vars, policy, thread_id);
+
+    if cfg!(target_os = "windows") {
+        // This is a workaround to address the failures we are seeing in the
+        // following tests when run via Bazel on Windows:
+        //
+        // ```
+        // suite::shell_command::unicode_output::with_login
+        // suite::shell_command::unicode_output::without_login
+        // ```
+        //
+        // Currently, we can only reproduce these failures in CI, which makes
+        // iteration times long, so we include this quick fix for now to unblock
+        // getting the Windows Bazel build running.
+        if !env_map.keys().any(|k| k.eq_ignore_ascii_case("PATHEXT")) {
+            env_map.insert("PATHEXT".to_string(), ".COM;.EXE;.BAT;.CMD".to_string());
+        }
+    }
+    env_map
+}
+
+pub fn populate_env<I>(
+    vars: I,
+    policy: &ShellEnvironmentPolicy,
+    thread_id: Option<&str>,
+) -> HashMap<String, String>
+where
+    I: IntoIterator<Item = (String, String)>,
+{
+    // Step 1 - determine the starting set of variables based on the
+    // `inherit` strategy.
+    let mut env_map: HashMap<String, String> = match policy.inherit {
+        ShellEnvironmentPolicyInherit::All => vars.into_iter().collect(),
+        ShellEnvironmentPolicyInherit::None => HashMap::new(),
+        ShellEnvironmentPolicyInherit::Core => {
+            let core_vars: HashSet<&str> = COMMON_CORE_VARS
+                .iter()
+                .copied()
+                .chain(PLATFORM_CORE_VARS.iter().copied())
+                .collect();
+            let is_core_var = |name: &str| {
+                if cfg!(target_os = "windows") {
+                    core_vars
+                        .iter()
+                        .any(|allowed| allowed.eq_ignore_ascii_case(name))
+                } else {
+                    core_vars.contains(name)
+                }
+            };
+            vars.into_iter().filter(|(k, _)| is_core_var(k)).collect()
+        }
+    };
+
+    // Internal helper - does `name` match any pattern in `patterns`?
+    let matches_any = |name: &str, patterns: &[EnvironmentVariablePattern]| -> bool {
+        patterns.iter().any(|pattern| pattern.matches(name))
+    };
+
+    // Step 2 - Apply the default exclude if not disabled.
+    if !policy.ignore_default_excludes {
+        let default_excludes = vec![
+            EnvironmentVariablePattern::new_case_insensitive("*KEY*"),
+            EnvironmentVariablePattern::new_case_insensitive("*SECRET*"),
+            EnvironmentVariablePattern::new_case_insensitive("*TOKEN*"),
+        ];
+        env_map.retain(|k, _| !matches_any(k, &default_excludes));
+    }
+
+    // Step 3 - Apply custom excludes.
+    if !policy.exclude.is_empty() {
+        env_map.retain(|k, _| !matches_any(k, &policy.exclude));
+    }
+
+    // Step 4 - Apply user-provided overrides.
+    for (key, val) in &policy.r#set {
+        env_map.insert(key.clone(), val.clone());
+    }
+
+    // Step 5 - If include_only is non-empty, keep only the matching vars.
+    if !policy.include_only.is_empty() {
+        env_map.retain(|k, _| matches_any(k, &policy.include_only));
+    }
+
+    // Step 6 - Populate the thread ID environment variable when provided.
+    if let Some(thread_id) = thread_id {
+        env_map.insert(CODEX_THREAD_ID_ENV_VAR.to_string(), thread_id.to_string());
+    }
+
+    env_map
+}
+
+const COMMON_CORE_VARS: &[&str] = &["PATH", "SHELL", "TMPDIR", "TEMP", "TMP"];
+
+#[cfg(target_os = "windows")]
+const PLATFORM_CORE_VARS: &[&str] = &["PATHEXT", "USERNAME", "USERPROFILE"];
+
+#[cfg(unix)]
+const PLATFORM_CORE_VARS: &[&str] = &["HOME", "LANG", "LC_ALL", "LC_CTYPE", "LOGNAME", "USER"];

codex-rs/config/src/types.rs

@@ -658,7 +658,7 @@ impl From<SandboxWorkspaceWrite> for codex_app_server_protocol::SandboxSettings
     }
 }
 
-#[derive(Serialize, Deserialize, Debug, Clone, PartialEq, Default, JsonSchema)]
+#[derive(Serialize, Deserialize, Debug, Clone, PartialEq, Eq, Default, JsonSchema)]
 #[serde(rename_all = "kebab-case")]
 pub enum ShellEnvironmentPolicyInherit {
     /// "Core" environment variables for the platform. On UNIX, this would

codex-rs/core/src/config/config_tests.rs

@@ -1525,7 +1525,7 @@ fn config_defaults_to_file_cli_auth_store_mode() -> std::io::Result<()> {
 }
 
 #[test]
-fn config_honors_explicit_keyring_auth_store_mode() -> std::io::Result<()> {
+fn config_resolves_explicit_keyring_auth_store_mode() -> std::io::Result<()> {
     let codex_home = TempDir::new()?;
     let cfg = ConfigToml {
         cli_auth_credentials_store: Some(AuthCredentialsStoreMode::Keyring),
@@ -1540,14 +1540,17 @@ fn config_honors_explicit_keyring_auth_store_mode() -> std::io::Result<()> {
 
     assert_eq!(
         config.cli_auth_credentials_store_mode,
-        AuthCredentialsStoreMode::Keyring,
+        resolve_cli_auth_credentials_store_mode(
+            AuthCredentialsStoreMode::Keyring,
+            env!("CARGO_PKG_VERSION"),
+        ),
     );
 
     Ok(())
 }
 
 #[test]
-fn config_defaults_to_auto_oauth_store_mode() -> std::io::Result<()> {
+fn config_resolves_default_oauth_store_mode() -> std::io::Result<()> {
     let codex_home = TempDir::new()?;
     let cfg = ConfigToml::default();
 
@@ -1559,12 +1562,66 @@ fn config_defaults_to_auto_oauth_store_mode() -> std::io::Result<()> {
 
     assert_eq!(
         config.mcp_oauth_credentials_store_mode,
-        OAuthCredentialsStoreMode::Auto,
+        resolve_mcp_oauth_credentials_store_mode(
+            OAuthCredentialsStoreMode::Auto,
+            env!("CARGO_PKG_VERSION"),
+        ),
     );
 
     Ok(())
 }
 
+#[test]
+fn local_dev_builds_force_file_cli_auth_store_modes() {
+    assert_eq!(
+        resolve_cli_auth_credentials_store_mode(
+            AuthCredentialsStoreMode::Keyring,
+            LOCAL_DEV_BUILD_VERSION,
+        ),
+        AuthCredentialsStoreMode::File,
+    );
+    assert_eq!(
+        resolve_cli_auth_credentials_store_mode(
+            AuthCredentialsStoreMode::Auto,
+            LOCAL_DEV_BUILD_VERSION,
+        ),
+        AuthCredentialsStoreMode::File,
+    );
+    assert_eq!(
+        resolve_cli_auth_credentials_store_mode(
+            AuthCredentialsStoreMode::Ephemeral,
+            LOCAL_DEV_BUILD_VERSION,
+        ),
+        AuthCredentialsStoreMode::Ephemeral,
+    );
+    assert_eq!(
+        resolve_cli_auth_credentials_store_mode(AuthCredentialsStoreMode::Keyring, "1.2.3"),
+        AuthCredentialsStoreMode::Keyring,
+    );
+}
+
+#[test]
+fn local_dev_builds_force_file_mcp_oauth_store_modes() {
+    assert_eq!(
+        resolve_mcp_oauth_credentials_store_mode(
+            OAuthCredentialsStoreMode::Keyring,
+            LOCAL_DEV_BUILD_VERSION,
+        ),
+        OAuthCredentialsStoreMode::File,
+    );
+    assert_eq!(
+        resolve_mcp_oauth_credentials_store_mode(
+            OAuthCredentialsStoreMode::Auto,
+            LOCAL_DEV_BUILD_VERSION,
+        ),
+        OAuthCredentialsStoreMode::File,
+    );
+    assert_eq!(
+        resolve_mcp_oauth_credentials_store_mode(OAuthCredentialsStoreMode::Keyring, "1.2.3"),
+        OAuthCredentialsStoreMode::Keyring,
+    );
+}
+
 #[test]
 fn feedback_enabled_defaults_to_true() -> std::io::Result<()> {
     let codex_home = TempDir::new()?;
@@ -1922,7 +1979,10 @@ async fn managed_config_overrides_oauth_store_mode() -> anyhow::Result<()> {
     )?;
     assert_eq!(
         final_config.mcp_oauth_credentials_store_mode,
-        OAuthCredentialsStoreMode::Keyring,
+        resolve_mcp_oauth_credentials_store_mode(
+            OAuthCredentialsStoreMode::Keyring,
+            env!("CARGO_PKG_VERSION"),
+        ),
     );
 
     Ok(())
@@ -4514,7 +4574,10 @@ fn test_precedence_fixture_with_o3_profile() -> std::io::Result<()> {
             cwd: fixture.cwd(),
             cli_auth_credentials_store_mode: Default::default(),
             mcp_servers: Constrained::allow_any(HashMap::new()),
-            mcp_oauth_credentials_store_mode: Default::default(),
+            mcp_oauth_credentials_store_mode: resolve_mcp_oauth_credentials_store_mode(
+                Default::default(),
+                LOCAL_DEV_BUILD_VERSION,
+            ),
             mcp_oauth_callback_port: None,
             mcp_oauth_callback_url: None,
             model_providers: fixture.model_provider_map.clone(),
@@ -4660,7 +4723,10 @@ fn test_precedence_fixture_with_gpt3_profile() -> std::io::Result<()> {
         cwd: fixture.cwd(),
         cli_auth_credentials_store_mode: Default::default(),
         mcp_servers: Constrained::allow_any(HashMap::new()),
-        mcp_oauth_credentials_store_mode: Default::default(),
+        mcp_oauth_credentials_store_mode: resolve_mcp_oauth_credentials_store_mode(
+            Default::default(),
+            LOCAL_DEV_BUILD_VERSION,
+        ),
         mcp_oauth_callback_port: None,
         mcp_oauth_callback_url: None,
         model_providers: fixture.model_provider_map.clone(),
@@ -4804,7 +4870,10 @@ fn test_precedence_fixture_with_zdr_profile() -> std::io::Result<()> {
         cwd: fixture.cwd(),
         cli_auth_credentials_store_mode: Default::default(),
         mcp_servers: Constrained::allow_any(HashMap::new()),
-        mcp_oauth_credentials_store_mode: Default::default(),
+        mcp_oauth_credentials_store_mode: resolve_mcp_oauth_credentials_store_mode(
+            Default::default(),
+            LOCAL_DEV_BUILD_VERSION,
+        ),
         mcp_oauth_callback_port: None,
         mcp_oauth_callback_url: None,
         model_providers: fixture.model_provider_map.clone(),
@@ -4934,7 +5003,10 @@ fn test_precedence_fixture_with_gpt5_profile() -> std::io::Result<()> {
         cwd: fixture.cwd(),
         cli_auth_credentials_store_mode: Default::default(),
         mcp_servers: Constrained::allow_any(HashMap::new()),
-        mcp_oauth_credentials_store_mode: Default::default(),
+        mcp_oauth_credentials_store_mode: resolve_mcp_oauth_credentials_store_mode(
+            Default::default(),
+            LOCAL_DEV_BUILD_VERSION,
+        ),
         mcp_oauth_callback_port: None,
         mcp_oauth_callback_url: None,
         model_providers: fixture.model_provider_map.clone(),

codex-rs/core/src/config/mod.rs

@@ -124,6 +124,7 @@ pub(crate) const PROJECT_DOC_MAX_BYTES: usize = 32 * 1024; // 32 KiB
 pub(crate) const DEFAULT_AGENT_MAX_THREADS: Option<usize> = Some(6);
 pub(crate) const DEFAULT_AGENT_MAX_DEPTH: i32 = 1;
 pub(crate) const DEFAULT_AGENT_JOB_MAX_RUNTIME_SECONDS: Option<u64> = None;
+const LOCAL_DEV_BUILD_VERSION: &str = "0.0.0";
 
 pub const CONFIG_TOML_FILE: &str = "config.toml";
 
@@ -141,6 +142,32 @@ fn resolve_sqlite_home_env(resolved_cwd: &Path) -> Option<PathBuf> {
     }
 }
 
+fn resolve_cli_auth_credentials_store_mode(
+    configured: AuthCredentialsStoreMode,
+    package_version: &str,
+) -> AuthCredentialsStoreMode {
+    match (package_version, configured) {
+        (
+            LOCAL_DEV_BUILD_VERSION,
+            AuthCredentialsStoreMode::Keyring | AuthCredentialsStoreMode::Auto,
+        ) => AuthCredentialsStoreMode::File,
+        (_, mode) => mode,
+    }
+}
+
+fn resolve_mcp_oauth_credentials_store_mode(
+    configured: OAuthCredentialsStoreMode,
+    package_version: &str,
+) -> OAuthCredentialsStoreMode {
+    match (package_version, configured) {
+        (
+            LOCAL_DEV_BUILD_VERSION,
+            OAuthCredentialsStoreMode::Keyring | OAuthCredentialsStoreMode::Auto,
+        ) => OAuthCredentialsStoreMode::File,
+        (_, mode) => mode,
+    }
+}
+
 #[cfg(test)]
 pub(crate) fn test_config() -> Config {
     let codex_home = tempfile::tempdir().expect("create temp dir");
@@ -2014,11 +2041,17 @@ impl Config {
             include_environment_context,
             // The config.toml omits "_mode" because it's a config file. However, "_mode"
             // is important in code to differentiate the mode from the store implementation.
-            cli_auth_credentials_store_mode: cfg.cli_auth_credentials_store.unwrap_or_default(),
+            cli_auth_credentials_store_mode: resolve_cli_auth_credentials_store_mode(
+                cfg.cli_auth_credentials_store.unwrap_or_default(),
+                env!("CARGO_PKG_VERSION"),
+            ),
             mcp_servers,
             // The config.toml omits "_mode" because it's a config file. However, "_mode"
             // is important in code to differentiate the mode from the store implementation.
-            mcp_oauth_credentials_store_mode: cfg.mcp_oauth_credentials_store.unwrap_or_default(),
+            mcp_oauth_credentials_store_mode: resolve_mcp_oauth_credentials_store_mode(
+                cfg.mcp_oauth_credentials_store.unwrap_or_default(),
+                env!("CARGO_PKG_VERSION"),
+            ),
             mcp_oauth_callback_port: cfg.mcp_oauth_callback_port,
             mcp_oauth_callback_url: cfg.mcp_oauth_callback_url.clone(),
             model_providers,

codex-rs/core/src/exec.rs

@@ -349,6 +349,7 @@ pub(crate) async fn execute_exec_request(
         command,
         cwd,
         env,
+        exec_server_env_config: _,
         network,
         expiration,
         capture_policy,

codex-rs/core/src/exec_env.rs

@@ -1,11 +1,10 @@
+#[cfg(test)]
 use codex_config::types::EnvironmentVariablePattern;
 use codex_config::types::ShellEnvironmentPolicy;
-use codex_config::types::ShellEnvironmentPolicyInherit;
 use codex_protocol::ThreadId;
 use std::collections::HashMap;
-use std::collections::HashSet;
 
-pub const CODEX_THREAD_ID_ENV_VAR: &str = "CODEX_THREAD_ID";
+pub use codex_config::shell_environment::CODEX_THREAD_ID_ENV_VAR;
 
 /// Construct an environment map based on the rules in the specified policy. The
 /// resulting map can be passed directly to `Command::envs()` after calling
@@ -21,9 +20,11 @@ pub fn create_env(
     policy: &ShellEnvironmentPolicy,
     thread_id: Option<ThreadId>,
 ) -> HashMap<String, String> {
-    create_env_from_vars(std::env::vars(), policy, thread_id)
+    let thread_id = thread_id.map(|thread_id| thread_id.to_string());
+    codex_config::shell_environment::create_env(policy, thread_id.as_deref())
 }
 
+#[cfg(all(test, target_os = "windows"))]
 fn create_env_from_vars<I>(
     vars: I,
     policy: &ShellEnvironmentPolicy,
@@ -32,35 +33,11 @@ fn create_env_from_vars<I>(
 where
     I: IntoIterator<Item = (String, String)>,
 {
-    let mut env_map = populate_env(vars, policy, thread_id);
-
-    if cfg!(target_os = "windows") {
-        // This is a workaround to address the failures we are seeing in the
-        // following tests when run via Bazel on Windows:
-        //
-        // ```
-        // suite::shell_command::unicode_output::with_login
-        // suite::shell_command::unicode_output::without_login
-        // ```
-        //
-        // Currently, we can only reproduce these failures in CI, which makes
-        // iteration times long, so we include this quick fix for now to unblock
-        // getting the Windows Bazel build running.
-        if !env_map.keys().any(|k| k.eq_ignore_ascii_case("PATHEXT")) {
-            env_map.insert("PATHEXT".to_string(), ".COM;.EXE;.BAT;.CMD".to_string());
-        }
-    }
-    env_map
+    let thread_id = thread_id.map(|thread_id| thread_id.to_string());
+    codex_config::shell_environment::create_env_from_vars(vars, policy, thread_id.as_deref())
 }
 
-const COMMON_CORE_VARS: &[&str] = &["PATH", "SHELL", "TMPDIR", "TEMP", "TMP"];
-
-#[cfg(target_os = "windows")]
-const PLATFORM_CORE_VARS: &[&str] = &["PATHEXT", "USERNAME", "USERPROFILE"];
-
-#[cfg(unix)]
-const PLATFORM_CORE_VARS: &[&str] = &["HOME", "LANG", "LC_ALL", "LC_CTYPE", "LOGNAME", "USER"];
-
+#[cfg(test)]
 fn populate_env<I>(
     vars: I,
     policy: &ShellEnvironmentPolicy,
@@ -69,66 +46,8 @@ fn populate_env<I>(
 where
     I: IntoIterator<Item = (String, String)>,
 {
-    // Step 1 – determine the starting set of variables based on the
-    // `inherit` strategy.
-    let mut env_map: HashMap<String, String> = match policy.inherit {
-        ShellEnvironmentPolicyInherit::All => vars.into_iter().collect(),
-        ShellEnvironmentPolicyInherit::None => HashMap::new(),
-        ShellEnvironmentPolicyInherit::Core => {
-            let core_vars: HashSet<&str> = COMMON_CORE_VARS
-                .iter()
-                .copied()
-                .chain(PLATFORM_CORE_VARS.iter().copied())
-                .collect();
-            let is_core_var = |name: &str| {
-                if cfg!(target_os = "windows") {
-                    core_vars
-                        .iter()
-                        .any(|allowed| allowed.eq_ignore_ascii_case(name))
-                } else {
-                    core_vars.contains(name)
-                }
-            };
-            vars.into_iter().filter(|(k, _)| is_core_var(k)).collect()
-        }
-    };
-
-    // Internal helper – does `name` match **any** pattern in `patterns`?
-    let matches_any = |name: &str, patterns: &[EnvironmentVariablePattern]| -> bool {
-        patterns.iter().any(|pattern| pattern.matches(name))
-    };
-
-    // Step 2 – Apply the default exclude if not disabled.
-    if !policy.ignore_default_excludes {
-        let default_excludes = vec![
-            EnvironmentVariablePattern::new_case_insensitive("*KEY*"),
-            EnvironmentVariablePattern::new_case_insensitive("*SECRET*"),
-            EnvironmentVariablePattern::new_case_insensitive("*TOKEN*"),
-        ];
-        env_map.retain(|k, _| !matches_any(k, &default_excludes));
-    }
-
-    // Step 3 – Apply custom excludes.
-    if !policy.exclude.is_empty() {
-        env_map.retain(|k, _| !matches_any(k, &policy.exclude));
-    }
-
-    // Step 4 – Apply user-provided overrides.
-    for (key, val) in &policy.r#set {
-        env_map.insert(key.clone(), val.clone());
-    }
-
-    // Step 5 – If include_only is non-empty, keep *only* the matching vars.
-    if !policy.include_only.is_empty() {
-        env_map.retain(|k, _| matches_any(k, &policy.include_only));
-    }
-
-    // Step 6 – Populate the thread ID environment variable when provided.
-    if let Some(thread_id) = thread_id {
-        env_map.insert(CODEX_THREAD_ID_ENV_VAR.to_string(), thread_id.to_string());
-    }
-
-    env_map
+    let thread_id = thread_id.map(|thread_id| thread_id.to_string());
+    codex_config::shell_environment::populate_env(vars, policy, thread_id.as_deref())
 }
 
 #[cfg(test)]

codex-rs/core/src/memories/mod.rs

@@ -65,7 +65,7 @@ mod phase_one {
 /// Phase 2 (aka `Consolidation`).
 mod phase_two {
     /// Default model used for phase 2.
-    pub(super) const MODEL: &str = "gpt-5.3-codex";
+    pub(super) const MODEL: &str = "gpt-5.4";
     /// Default reasoning effort used for phase 2.
     pub(super) const REASONING_EFFORT: super::ReasoningEffort = super::ReasoningEffort::Medium;
     /// Lease duration (seconds) for phase-2 consolidation job ownership.

codex-rs/core/src/sandboxing/mod.rs

@@ -33,11 +33,18 @@ pub(crate) struct ExecOptions {
     pub(crate) capture_policy: ExecCapturePolicy,
 }
 
+#[derive(Clone, Debug)]
+pub(crate) struct ExecServerEnvConfig {
+    pub(crate) policy: codex_exec_server::ExecEnvPolicy,
+    pub(crate) local_policy_env: HashMap<String, String>,
+}
+
 #[derive(Debug)]
 pub struct ExecRequest {
     pub command: Vec<String>,
     pub cwd: AbsolutePathBuf,
     pub env: HashMap<String, String>,
+    pub(crate) exec_server_env_config: Option<ExecServerEnvConfig>,
     pub network: Option<NetworkProxy>,
     pub expiration: ExecExpiration,
     pub capture_policy: ExecCapturePolicy,
@@ -72,6 +79,7 @@ impl ExecRequest {
             command,
             cwd,
             env,
+            exec_server_env_config: None,
             network,
             expiration,
             capture_policy,
@@ -121,6 +129,7 @@ impl ExecRequest {
             command,
             cwd,
             env,
+            exec_server_env_config: None,
             network,
             expiration,
             capture_policy,

codex-rs/core/src/tasks/user_shell.rs

@@ -162,6 +162,7 @@ pub(crate) async fn execute_user_shell_command(
         command: exec_command.clone(),
         cwd: cwd.clone(),
         env: exec_env_map,
+        exec_server_env_config: None,
         network: turn_context.network.clone(),
         // TODO(zhao-oai): Now that we have ExecExpiration::Cancellation, we
         // should use that instead of an "arbitrarily large" timeout here.

codex-rs/core/src/tools/runtimes/shell/unix_escalation.rs

@@ -126,6 +126,7 @@ pub(super) async fn try_run_zsh_fork(
         command,
         cwd: sandbox_cwd,
         env: sandbox_env,
+        exec_server_env_config: _,
         network: sandbox_network,
         expiration: _sandbox_expiration,
         capture_policy: _capture_policy,
@@ -734,6 +735,7 @@ impl ShellCommandExecutor for CoreShellCommandExecutor {
                 command: self.command.clone(),
                 cwd: self.cwd.clone(),
                 env: exec_env,
+                exec_server_env_config: None,
                 network: self.network.clone(),
                 expiration: ExecExpiration::Cancellation(cancel_rx),
                 capture_policy: ExecCapturePolicy::ShellTool,

codex-rs/core/src/tools/runtimes/unified_exec.rs

@@ -10,6 +10,7 @@ use crate::exec::ExecExpiration;
 use crate::guardian::GuardianApprovalRequest;
 use crate::guardian::review_approval_request;
 use crate::sandboxing::ExecOptions;
+use crate::sandboxing::ExecServerEnvConfig;
 use crate::sandboxing::SandboxPermissions;
 use crate::shell::ShellType;
 use crate::tools::network_approval::NetworkApprovalMode;
@@ -52,6 +53,7 @@ pub struct UnifiedExecRequest {
     pub process_id: i32,
     pub cwd: AbsolutePathBuf,
     pub env: HashMap<String, String>,
+    pub exec_server_env_config: Option<ExecServerEnvConfig>,
     pub explicit_env_overrides: HashMap<String, String>,
     pub network: Option<NetworkProxy>,
     pub tty: bool,
@@ -237,9 +239,10 @@ impl<'a> ToolRuntime<UnifiedExecRequest, UnifiedExecProcess> for UnifiedExecRunt
                 expiration: ExecExpiration::DefaultTimeout,
                 capture_policy: ExecCapturePolicy::ShellTool,
             };
-            let exec_env = attempt
+            let mut exec_env = attempt
                 .env_for(command, options, req.network.as_ref())
                 .map_err(|err| ToolError::Codex(err.into()))?;
+            exec_env.exec_server_env_config = req.exec_server_env_config.clone();
             match zsh_fork_backend::maybe_prepare_unified_exec(
                 req,
                 attempt,
@@ -294,9 +297,10 @@ impl<'a> ToolRuntime<UnifiedExecRequest, UnifiedExecProcess> for UnifiedExecRunt
             expiration: ExecExpiration::DefaultTimeout,
             capture_policy: ExecCapturePolicy::ShellTool,
         };
-        let exec_env = attempt
+        let mut exec_env = attempt
             .env_for(command, options, req.network.as_ref())
             .map_err(|err| ToolError::Codex(err.into()))?;
+        exec_env.exec_server_env_config = req.exec_server_env_config.clone();
         let Some(environment) = ctx.turn.environment.as_ref() else {
             return Err(ToolError::Rejected(
                 "exec_command is unavailable in this session".to_string(),

codex-rs/core/src/unified_exec/process.rs

@@ -66,10 +66,11 @@ pub(crate) struct OutputHandles {
 /// Transport-specific process handle used by unified exec.
 enum ProcessHandle {
     Local(Box<ExecCommandSession>),
-    Remote(Arc<dyn ExecProcess>),
+    ExecServer(Arc<dyn ExecProcess>),
 }
 
-/// Unified wrapper over local PTY sessions and exec-server-backed processes.
+/// Unified wrapper over directly spawned PTY sessions and exec-server-backed
+/// processes.
 pub(crate) struct UnifiedExecProcess {
     process_handle: ProcessHandle,
     output_tx: broadcast::Sender<Vec<u8>>,
@@ -135,7 +136,7 @@ impl UnifiedExecProcess {
                 .send(data.to_vec())
                 .await
                 .map_err(|_| UnifiedExecError::WriteToStdin),
-            ProcessHandle::Remote(process_handle) => {
+            ProcessHandle::ExecServer(process_handle) => {
                 match process_handle.write(data.to_vec()).await {
                     Ok(response) => match response.status {
                         WriteStatus::Accepted => Ok(()),
@@ -179,7 +180,7 @@ impl UnifiedExecProcess {
         let state = self.state_rx.borrow().clone();
         match &self.process_handle {
             ProcessHandle::Local(process_handle) => state.has_exited || process_handle.has_exited(),
-            ProcessHandle::Remote(_) => state.has_exited,
+            ProcessHandle::ExecServer(_) => state.has_exited,
         }
     }
 
@@ -189,7 +190,7 @@ impl UnifiedExecProcess {
             ProcessHandle::Local(process_handle) => {
                 state.exit_code.or_else(|| process_handle.exit_code())
             }
-            ProcessHandle::Remote(_) => state.exit_code,
+            ProcessHandle::ExecServer(_) => state.exit_code,
         }
     }
 
@@ -198,7 +199,7 @@ impl UnifiedExecProcess {
         self.output_closed_notify.notify_waiters();
         match &self.process_handle {
             ProcessHandle::Local(process_handle) => process_handle.terminate(),
-            ProcessHandle::Remote(process_handle) => {
+            ProcessHandle::ExecServer(process_handle) => {
                 let process_handle = Arc::clone(process_handle);
                 tokio::spawn(async move {
                     let _ = process_handle.terminate().await;
@@ -331,14 +332,14 @@ impl UnifiedExecProcess {
         Ok(managed)
     }
 
-    pub(super) async fn from_remote_started(
+    pub(super) async fn from_exec_server_started(
         started: StartedExecProcess,
         sandbox_type: SandboxType,
     ) -> Result<Self, UnifiedExecError> {
-        let process_handle = ProcessHandle::Remote(Arc::clone(&started.process));
+        let process_handle = ProcessHandle::ExecServer(Arc::clone(&started.process));
         let mut managed = Self::new(process_handle, sandbox_type, /*spawn_lifecycle*/ None);
         let output_handles = managed.output_handles();
-        managed.output_task = Some(Self::spawn_remote_output_task(
+        managed.output_task = Some(Self::spawn_exec_server_output_task(
             started,
             output_handles,
             managed.output_tx.clone(),
@@ -366,7 +367,7 @@ impl UnifiedExecProcess {
         Ok(managed)
     }
 
-    fn spawn_remote_output_task(
+    fn spawn_exec_server_output_task(
         started: StartedExecProcess,
         output_handles: OutputHandles,
         output_tx: broadcast::Sender<Vec<u8>>,

codex-rs/core/src/unified_exec/process_manager.rs

@@ -11,9 +11,11 @@ use tokio::time::Duration;
 use tokio::time::Instant;
 use tokio_util::sync::CancellationToken;
 
+use crate::exec_env::CODEX_THREAD_ID_ENV_VAR;
 use crate::exec_env::create_env;
 use crate::exec_policy::ExecApprovalRequest;
 use crate::sandboxing::ExecRequest;
+use crate::sandboxing::ExecServerEnvConfig;
 use crate::tools::context::ExecCommandToolOutput;
 use crate::tools::events::ToolEmitter;
 use crate::tools::events::ToolEventCtx;
@@ -47,6 +49,7 @@ use crate::unified_exec::process::OutputBuffer;
 use crate::unified_exec::process::OutputHandles;
 use crate::unified_exec::process::SpawnLifecycleHandle;
 use crate::unified_exec::process::UnifiedExecProcess;
+use codex_config::types::ShellEnvironmentPolicy;
 use codex_protocol::protocol::ExecCommandSource;
 use codex_utils_absolute_path::AbsolutePathBuf;
 use codex_utils_output_truncation::approx_token_count;
@@ -89,6 +92,70 @@ fn apply_unified_exec_env(mut env: HashMap<String, String>) -> HashMap<String, S
     env
 }
 
+fn exec_env_policy_from_shell_policy(
+    policy: &ShellEnvironmentPolicy,
+) -> codex_exec_server::ExecEnvPolicy {
+    codex_exec_server::ExecEnvPolicy {
+        inherit: policy.inherit.clone(),
+        ignore_default_excludes: policy.ignore_default_excludes,
+        exclude: policy
+            .exclude
+            .iter()
+            .map(std::string::ToString::to_string)
+            .collect(),
+        r#set: policy.r#set.clone(),
+        include_only: policy
+            .include_only
+            .iter()
+            .map(std::string::ToString::to_string)
+            .collect(),
+    }
+}
+
+fn env_overlay_for_exec_server(
+    request_env: &HashMap<String, String>,
+    local_policy_env: &HashMap<String, String>,
+) -> HashMap<String, String> {
+    request_env
+        .iter()
+        .filter(|(key, value)| local_policy_env.get(*key) != Some(*value))
+        .map(|(key, value)| (key.clone(), value.clone()))
+        .collect()
+}
+
+fn exec_server_env_for_request(
+    request: &ExecRequest,
+) -> (
+    Option<codex_exec_server::ExecEnvPolicy>,
+    HashMap<String, String>,
+) {
+    if let Some(exec_server_env_config) = &request.exec_server_env_config {
+        (
+            Some(exec_server_env_config.policy.clone()),
+            env_overlay_for_exec_server(&request.env, &exec_server_env_config.local_policy_env),
+        )
+    } else {
+        (None, request.env.clone())
+    }
+}
+
+fn exec_server_params_for_request(
+    process_id: i32,
+    request: &ExecRequest,
+    tty: bool,
+) -> codex_exec_server::ExecParams {
+    let (env_policy, env) = exec_server_env_for_request(request);
+    codex_exec_server::ExecParams {
+        process_id: exec_server_process_id(process_id).into(),
+        argv: request.command.clone(),
+        cwd: request.cwd.to_path_buf(),
+        env_policy,
+        env,
+        tty,
+        arg0: request.arg0.clone(),
+    }
+}
+
 /// Borrowed process state prepared for a `write_stdin` or poll operation.
 struct PreparedProcessHandles {
     process: Arc<UnifiedExecProcess>,
@@ -587,12 +654,7 @@ impl UnifiedExecProcessManager {
         mut spawn_lifecycle: SpawnLifecycleHandle,
         environment: &codex_exec_server::Environment,
     ) -> Result<UnifiedExecProcess, UnifiedExecError> {
-        let (program, args) = request
-            .command
-            .split_first()
-            .ok_or(UnifiedExecError::MissingCommandLine)?;
         let inherited_fds = spawn_lifecycle.inherited_fds();
-
         if environment.is_remote() {
             if !inherited_fds.is_empty() {
                 return Err(UnifiedExecError::create_process(
@@ -602,19 +664,17 @@ impl UnifiedExecProcessManager {
 
             let started = environment
                 .get_exec_backend()
-                .start(codex_exec_server::ExecParams {
-                    process_id: exec_server_process_id(process_id).into(),
-                    argv: request.command.clone(),
-                    cwd: request.cwd.to_path_buf(),
-                    env: request.env.clone(),
-                    tty,
-                    arg0: request.arg0.clone(),
-                })
+                .start(exec_server_params_for_request(process_id, request, tty))
                 .await
                 .map_err(|err| UnifiedExecError::create_process(err.to_string()))?;
-            return UnifiedExecProcess::from_remote_started(started, request.sandbox).await;
+            spawn_lifecycle.after_spawn();
+            return UnifiedExecProcess::from_exec_server_started(started, request.sandbox).await;
         }
 
+        let (program, args) = request
+            .command
+            .split_first()
+            .ok_or(UnifiedExecError::MissingCommandLine)?;
         let spawn_result = if tty {
             codex_utils_pty::pty::spawn_process_with_inherited_fds(
                 program,
@@ -649,10 +709,20 @@ impl UnifiedExecProcessManager {
         cwd: AbsolutePathBuf,
         context: &UnifiedExecContext,
     ) -> Result<(UnifiedExecProcess, Option<DeferredNetworkApproval>), UnifiedExecError> {
-        let env = apply_unified_exec_env(create_env(
+        let local_policy_env = create_env(
             &context.turn.shell_environment_policy,
-            Some(context.session.conversation_id),
-        ));
+            /*thread_id*/ None,
+        );
+        let mut env = local_policy_env.clone();
+        env.insert(
+            CODEX_THREAD_ID_ENV_VAR.to_string(),
+            context.session.conversation_id.to_string(),
+        );
+        let env = apply_unified_exec_env(env);
+        let exec_server_env_config = ExecServerEnvConfig {
+            policy: exec_env_policy_from_shell_policy(&context.turn.shell_environment_policy),
+            local_policy_env,
+        };
         let mut orchestrator = ToolOrchestrator::new();
         let mut runtime = UnifiedExecRuntime::new(
             self,
@@ -680,6 +750,7 @@ impl UnifiedExecProcessManager {
             process_id: request.process_id,
             cwd,
             env,
+            exec_server_env_config: Some(exec_server_env_config),
             explicit_env_overrides: context.turn.shell_environment_policy.r#set.clone(),
             network: request.network.clone(),
             tty: request.tty,

codex-rs/core/src/unified_exec/process_manager_tests.rs

@@ -34,6 +34,92 @@ fn unified_exec_env_overrides_existing_values() {
     assert_eq!(env.get("PATH"), Some(&"/usr/bin".to_string()));
 }
 
+#[test]
+fn env_overlay_for_exec_server_keeps_runtime_changes_only() {
+    let local_policy_env = HashMap::from([
+        ("HOME".to_string(), "/client-home".to_string()),
+        ("PATH".to_string(), "/client-path".to_string()),
+        ("SHELL_SET".to_string(), "policy".to_string()),
+    ]);
+    let request_env = HashMap::from([
+        ("HOME".to_string(), "/client-home".to_string()),
+        ("PATH".to_string(), "/sandbox-path".to_string()),
+        ("SHELL_SET".to_string(), "policy".to_string()),
+        ("CODEX_THREAD_ID".to_string(), "thread-1".to_string()),
+        (
+            "CODEX_SANDBOX_NETWORK_DISABLED".to_string(),
+            "1".to_string(),
+        ),
+    ]);
+
+    assert_eq!(
+        env_overlay_for_exec_server(&request_env, &local_policy_env),
+        HashMap::from([
+            ("PATH".to_string(), "/sandbox-path".to_string()),
+            ("CODEX_THREAD_ID".to_string(), "thread-1".to_string()),
+            (
+                "CODEX_SANDBOX_NETWORK_DISABLED".to_string(),
+                "1".to_string()
+            ),
+        ])
+    );
+}
+
+#[test]
+fn exec_server_params_use_env_policy_overlay_contract() {
+    let request = ExecRequest {
+        command: vec!["bash".to_string(), "-lc".to_string(), "true".to_string()],
+        cwd: std::env::current_dir()
+            .expect("current dir")
+            .try_into()
+            .expect("absolute path"),
+        env: HashMap::from([
+            ("HOME".to_string(), "/client-home".to_string()),
+            ("PATH".to_string(), "/sandbox-path".to_string()),
+            ("CODEX_THREAD_ID".to_string(), "thread-1".to_string()),
+        ]),
+        exec_server_env_config: Some(ExecServerEnvConfig {
+            policy: codex_exec_server::ExecEnvPolicy {
+                inherit: codex_config::types::ShellEnvironmentPolicyInherit::Core,
+                ignore_default_excludes: false,
+                exclude: Vec::new(),
+                r#set: HashMap::new(),
+                include_only: Vec::new(),
+            },
+            local_policy_env: HashMap::from([
+                ("HOME".to_string(), "/client-home".to_string()),
+                ("PATH".to_string(), "/client-path".to_string()),
+            ]),
+        }),
+        network: None,
+        expiration: crate::exec::ExecExpiration::DefaultTimeout,
+        capture_policy: crate::exec::ExecCapturePolicy::ShellTool,
+        sandbox: codex_sandboxing::SandboxType::None,
+        windows_sandbox_level: codex_protocol::config_types::WindowsSandboxLevel::Disabled,
+        windows_sandbox_private_desktop: false,
+        sandbox_policy: codex_protocol::protocol::SandboxPolicy::DangerFullAccess,
+        file_system_sandbox_policy: codex_protocol::permissions::FileSystemSandboxPolicy::from(
+            &codex_protocol::protocol::SandboxPolicy::DangerFullAccess,
+        ),
+        network_sandbox_policy: codex_protocol::permissions::NetworkSandboxPolicy::Restricted,
+        windows_sandbox_filesystem_overrides: None,
+        arg0: None,
+    };
+
+    let params =
+        exec_server_params_for_request(/*process_id*/ 123, &request, /*tty*/ true);
+
+    assert_eq!(params.process_id.as_str(), "123");
+    assert!(params.env_policy.is_some());
+    assert_eq!(
+        params.env,
+        HashMap::from([
+            ("PATH".to_string(), "/sandbox-path".to_string()),
+            ("CODEX_THREAD_ID".to_string(), "thread-1".to_string()),
+        ])
+    );
+}
+
 #[test]
 fn exec_server_process_id_matches_unified_exec_process_id() {
     assert_eq!(exec_server_process_id(/*process_id*/ 4321), "4321");

codex-rs/core/src/unified_exec/process_tests.rs

@@ -76,7 +76,7 @@ async fn remote_process(write_status: WriteStatus) -> UnifiedExecProcess {
         }),
     };
 
-    UnifiedExecProcess::from_remote_started(started, SandboxType::None)
+    UnifiedExecProcess::from_exec_server_started(started, SandboxType::None)
         .await
         .expect("remote process should start")
 }
@@ -133,7 +133,7 @@ async fn remote_process_waits_for_early_exit_event() {
         let _ = wake_tx.send(1);
     });
 
-    let process = UnifiedExecProcess::from_remote_started(started, SandboxType::None)
+    let process = UnifiedExecProcess::from_exec_server_started(started, SandboxType::None)
         .await
         .expect("remote process should observe early exit");
 

codex-rs/exec-server/Cargo.toml

@@ -15,6 +15,7 @@ arc-swap = { workspace = true }
 async-trait = { workspace = true }
 base64 = { workspace = true }
 codex-app-server-protocol = { workspace = true }
+codex-config = { workspace = true }
 codex-protocol = { workspace = true }
 codex-sandboxing = { workspace = true }
 codex-utils-absolute-path = { workspace = true }
@@ -42,5 +43,6 @@ uuid = { workspace = true, features = ["v4"] }
 anyhow = { workspace = true }
 codex-utils-cargo-bin = { workspace = true }
 pretty_assertions = { workspace = true }
+serial_test = { workspace = true }
 tempfile = { workspace = true }
 test-case = "3.3.1"

codex-rs/exec-server/src/environment.rs

@@ -343,6 +343,7 @@ mod tests {
                 process_id: ProcessId::from("default-env-proc"),
                 argv: vec!["true".to_string()],
                 cwd: std::env::current_dir().expect("read current dir"),
+                env_policy: None,
                 env: Default::default(),
                 tty: false,
                 arg0: None,

codex-rs/exec-server/src/lib.rs

@@ -42,6 +42,7 @@ pub use process::ExecProcess;
 pub use process::StartedExecProcess;
 pub use process_id::ProcessId;
 pub use protocol::ExecClosedNotification;
+pub use protocol::ExecEnvPolicy;
 pub use protocol::ExecExitedNotification;
 pub use protocol::ExecOutputDeltaNotification;
 pub use protocol::ExecOutputStream;

codex-rs/exec-server/src/local_process.rs

@@ -5,6 +5,9 @@ use std::time::Duration;
 
 use async_trait::async_trait;
 use codex_app_server_protocol::JSONRPCErrorError;
+use codex_config::shell_environment;
+use codex_config::types::EnvironmentVariablePattern;
+use codex_config::types::ShellEnvironmentPolicy;
 use codex_utils_pty::ExecCommandSession;
 use codex_utils_pty::TerminalSize;
 use tokio::sync::Mutex;
@@ -19,6 +22,7 @@ use crate::ProcessId;
 use crate::StartedExecProcess;
 use crate::protocol::EXEC_CLOSED_METHOD;
 use crate::protocol::ExecClosedNotification;
+use crate::protocol::ExecEnvPolicy;
 use crate::protocol::ExecExitedNotification;
 use crate::protocol::ExecOutputDeltaNotification;
 use crate::protocol::ExecOutputStream;
@@ -150,12 +154,13 @@ impl LocalProcess {
             process_map.insert(process_id.clone(), ProcessEntry::Starting);
         }
 
+        let env = child_env(&params);
         let spawned_result = if params.tty {
             codex_utils_pty::spawn_pty_process(
                 program,
                 args,
                 params.cwd.as_path(),
-                &params.env,
+                &env,
                 &params.arg0,
                 TerminalSize::default(),
             )
@@ -165,7 +170,7 @@ impl LocalProcess {
                 program,
                 args,
                 params.cwd.as_path(),
-                &params.env,
+                &env,
                 &params.arg0,
             )
             .await
@@ -375,6 +380,36 @@ impl LocalProcess {
     }
 }
 
+fn child_env(params: &ExecParams) -> HashMap<String, String> {
+    let Some(env_policy) = &params.env_policy else {
+        return params.env.clone();
+    };
+
+    let policy = shell_environment_policy(env_policy);
+    let mut env = shell_environment::create_env(&policy, /*thread_id*/ None);
+    env.extend(params.env.clone());
+    env
+}
+
+fn shell_environment_policy(env_policy: &ExecEnvPolicy) -> ShellEnvironmentPolicy {
+    ShellEnvironmentPolicy {
+        inherit: env_policy.inherit.clone(),
+        ignore_default_excludes: env_policy.ignore_default_excludes,
+        exclude: env_policy
+            .exclude
+            .iter()
+            .map(|pattern| EnvironmentVariablePattern::new_case_insensitive(pattern))
+            .collect(),
+        r#set: env_policy.r#set.clone(),
+        include_only: env_policy
+            .include_only
+            .iter()
+            .map(|pattern| EnvironmentVariablePattern::new_case_insensitive(pattern))
+            .collect(),
+        use_profile: false,
+    }
+}
+
 #[async_trait]
 impl ExecBackend for LocalProcess {
     async fn start(&self, params: ExecParams) -> Result<StartedExecProcess, ExecServerError> {
@@ -618,3 +653,56 @@ fn notification_sender(inner: &Inner) -> Option<RpcNotificationSender> {
         .unwrap_or_else(std::sync::PoisonError::into_inner)
         .clone()
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use codex_config::types::ShellEnvironmentPolicyInherit;
+
+    fn test_exec_params(env: HashMap<String, String>) -> ExecParams {
+        ExecParams {
+            process_id: ProcessId::from("env-test"),
+            argv: vec!["true".to_string()],
+            cwd: std::path::PathBuf::from("/tmp"),
+            env_policy: None,
+            env,
+            tty: false,
+            arg0: None,
+        }
+    }
+
+    #[test]
+    fn child_env_defaults_to_exact_env() {
+        let params = test_exec_params(HashMap::from([("ONLY_THIS".to_string(), "1".to_string())]));
+
+        assert_eq!(
+            child_env(&params),
+            HashMap::from([("ONLY_THIS".to_string(), "1".to_string())])
+        );
+    }
+
+    #[test]
+    fn child_env_applies_policy_then_overlay() {
+        let mut params = test_exec_params(HashMap::from([
+            ("OVERLAY".to_string(), "overlay".to_string()),
+            ("POLICY_SET".to_string(), "overlay-wins".to_string()),
+        ]));
+        params.env_policy = Some(ExecEnvPolicy {
+            inherit: ShellEnvironmentPolicyInherit::None,
+            ignore_default_excludes: true,
+            exclude: Vec::new(),
+            r#set: HashMap::from([("POLICY_SET".to_string(), "policy".to_string())]),
+            include_only: Vec::new(),
+        });
+
+        let mut expected = HashMap::from([
+            ("OVERLAY".to_string(), "overlay".to_string()),
+            ("POLICY_SET".to_string(), "overlay-wins".to_string()),
+        ]);
+        if cfg!(target_os = "windows") {
+            expected.insert("PATHEXT".to_string(), ".COM;.EXE;.BAT;.CMD".to_string());
+        }
+
+        assert_eq!(child_env(&params), expected);
+    }
+}

codex-rs/exec-server/src/protocol.rs

@@ -3,6 +3,7 @@ use std::path::PathBuf;
 
 use crate::FileSystemSandboxContext;
 use base64::engine::general_purpose::STANDARD as BASE64_STANDARD;
+use codex_config::types::ShellEnvironmentPolicyInherit;
 use codex_utils_absolute_path::AbsolutePathBuf;
 use serde::Deserialize;
 use serde::Serialize;
@@ -64,11 +65,23 @@ pub struct ExecParams {
     pub process_id: ProcessId,
     pub argv: Vec<String>,
     pub cwd: PathBuf,
+    #[serde(default)]
+    pub env_policy: Option<ExecEnvPolicy>,
     pub env: HashMap<String, String>,
     pub tty: bool,
     pub arg0: Option<String>,
 }
 
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct ExecEnvPolicy {
+    pub inherit: ShellEnvironmentPolicyInherit,
+    pub ignore_default_excludes: bool,
+    pub exclude: Vec<String>,
+    pub r#set: HashMap<String, String>,
+    pub include_only: Vec<String>,
+}
+
 #[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
 #[serde(rename_all = "camelCase")]
 pub struct ExecResponse {

codex-rs/exec-server/src/server/handler/tests.rs

@@ -27,6 +27,7 @@ fn exec_params_with_argv(process_id: &str, argv: Vec<String>) -> ExecParams {
         process_id: ProcessId::from(process_id),
         argv,
         cwd: std::env::current_dir().expect("cwd"),
+        env_policy: None,
         env: inherited_path_env(),
         tty: false,
         arg0: None,

codex-rs/exec-server/src/server/processor.rs

@@ -390,6 +390,7 @@ mod tests {
             process_id,
             argv: sleep_then_print_argv(),
             cwd: std::env::current_dir().expect("cwd"),
+            env_policy: None,
             env,
             tty: false,
             arg0: None,

codex-rs/exec-server/tests/common/exec_server.rs

@@ -47,6 +47,7 @@ pub(crate) async fn exec_server() -> anyhow::Result<ExecServerHarness> {
     child.stdin(Stdio::null());
     child.stdout(Stdio::piped());
     child.stderr(Stdio::inherit());
+    child.kill_on_drop(true);
     let mut child = child.spawn()?;
 
     let websocket_url = read_listen_url_from_stdout(&mut child).await?;
@@ -140,6 +141,9 @@ impl ExecServerHarness {
 
     pub(crate) async fn shutdown(&mut self) -> anyhow::Result<()> {
         self.child.start_kill()?;
+        timeout(CONNECT_TIMEOUT, self.child.wait())
+            .await
+            .map_err(|_| anyhow!("timed out waiting for exec-server shutdown"))??;
         Ok(())
     }
 

codex-rs/exec-server/tests/exec_process.rs

@@ -51,6 +51,7 @@ async fn assert_exec_process_starts_and_exits(use_remote: bool) -> Result<()> {
             process_id: ProcessId::from("proc-1"),
             argv: vec!["true".to_string()],
             cwd: std::env::current_dir()?,
+            env_policy: /*env_policy*/ None,
             env: Default::default(),
             tty: false,
             arg0: None,
@@ -127,6 +128,7 @@ async fn assert_exec_process_streams_output(use_remote: bool) -> Result<()> {
                 "sleep 0.05; printf 'session output\\n'".to_string(),
             ],
             cwd: std::env::current_dir()?,
+            env_policy: /*env_policy*/ None,
             env: Default::default(),
             tty: false,
             arg0: None,
@@ -156,6 +158,7 @@ async fn assert_exec_process_write_then_read(use_remote: bool) -> Result<()> {
                 "import sys; line = sys.stdin.readline(); sys.stdout.write(f'from-stdin:{line}'); sys.stdout.flush()".to_string(),
             ],
             cwd: std::env::current_dir()?,
+            env_policy: /*env_policy*/ None,
             env: Default::default(),
             tty: true,
             arg0: None,
@@ -192,6 +195,7 @@ async fn assert_exec_process_preserves_queued_events_before_subscribe(
                 "printf 'queued output\\n'".to_string(),
             ],
             cwd: std::env::current_dir()?,
+            env_policy: /*env_policy*/ None,
             env: Default::default(),
             tty: false,
             arg0: None,
@@ -210,6 +214,8 @@ async fn assert_exec_process_preserves_queued_events_before_subscribe(
 }
 
 #[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+// Serialize tests that launch a real exec-server process through the full CLI.
+#[serial_test::serial(remote_exec_server)]
 async fn remote_exec_process_reports_transport_disconnect() -> Result<()> {
     let mut context = create_process_context(/*use_remote*/ true).await?;
     let session = context
@@ -222,6 +228,7 @@ async fn remote_exec_process_reports_transport_disconnect() -> Result<()> {
                 "sleep 10".to_string(),
             ],
             cwd: std::env::current_dir()?,
+            env_policy: /*env_policy*/ None,
             env: Default::default(),
             tty: false,
             arg0: None,
@@ -255,6 +262,8 @@ async fn remote_exec_process_reports_transport_disconnect() -> Result<()> {
 #[test_case(false ; "local")]
 #[test_case(true ; "remote")]
 #[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+// Serialize tests that launch a real exec-server process through the full CLI.
+#[serial_test::serial(remote_exec_server)]
 async fn exec_process_starts_and_exits(use_remote: bool) -> Result<()> {
     assert_exec_process_starts_and_exits(use_remote).await
 }
@@ -262,6 +271,8 @@ async fn exec_process_starts_and_exits(use_remote: bool) -> Result<()> {
 #[test_case(false ; "local")]
 #[test_case(true ; "remote")]
 #[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+// Serialize tests that launch a real exec-server process through the full CLI.
+#[serial_test::serial(remote_exec_server)]
 async fn exec_process_streams_output(use_remote: bool) -> Result<()> {
     assert_exec_process_streams_output(use_remote).await
 }
@@ -269,6 +280,8 @@ async fn exec_process_streams_output(use_remote: bool) -> Result<()> {
 #[test_case(false ; "local")]
 #[test_case(true ; "remote")]
 #[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+// Serialize tests that launch a real exec-server process through the full CLI.
+#[serial_test::serial(remote_exec_server)]
 async fn exec_process_write_then_read(use_remote: bool) -> Result<()> {
     assert_exec_process_write_then_read(use_remote).await
 }
@@ -276,6 +289,8 @@ async fn exec_process_write_then_read(use_remote: bool) -> Result<()> {
 #[test_case(false ; "local")]
 #[test_case(true ; "remote")]
 #[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+// Serialize tests that launch a real exec-server process through the full CLI.
+#[serial_test::serial(remote_exec_server)]
 async fn exec_process_preserves_queued_events_before_subscribe(use_remote: bool) -> Result<()> {
     assert_exec_process_preserves_queued_events_before_subscribe(use_remote).await
 }

codex-rs/login/src/auth/storage.rs

@@ -2,6 +2,7 @@ use chrono::DateTime;
 use chrono::Utc;
 use serde::Deserialize;
 use serde::Serialize;
+use serde::de::DeserializeOwned;
 use sha2::Digest;
 use sha2::Sha256;
 use std::collections::HashMap;
@@ -119,6 +120,14 @@ impl AuthStorageBackend for FileAuthStorage {
 
 const KEYRING_SERVICE: &str = "Codex Auth";
 
+// Const for each field of AuthDotJson, only when used on windows
+// if more fields are added to struct, then update these consts
+//  and windows storage functions.
+const AUTH_MODE_FIELD: &str = "auth_mode";
+const OPENAI_API_KEY_FIELD: &str = "openai_api_key";
+const TOKENS_FIELD: &str = "tokens";
+const LAST_REFRESH_FIELD: &str = "last_refresh";
+
 // turns codex_home path into a stable, short key string
 fn compute_store_key(codex_home: &Path) -> std::io::Result<String> {
     let canonical = codex_home
@@ -175,19 +184,139 @@ impl KeyringAuthStorage {
             }
         }
     }
+
+    fn field_key(key: &str, field_name: &str) -> String {
+        format!("{key}|{field_name}")
+    }
+
+    fn save_windows_auth_to_keyring(&self, key: &str, auth: &AuthDotJson) -> std::io::Result<()> {
+        let fields = [
+            (
+                AUTH_MODE_FIELD,
+                serde_json::to_string(&auth.auth_mode).map_err(std::io::Error::other)?,
+            ),
+            (
+                OPENAI_API_KEY_FIELD,
+                serde_json::to_string(&auth.openai_api_key).map_err(std::io::Error::other)?,
+            ),
+            (
+                TOKENS_FIELD,
+                serde_json::to_string(&auth.tokens).map_err(std::io::Error::other)?,
+            ),
+            (
+                LAST_REFRESH_FIELD,
+                serde_json::to_string(&auth.last_refresh).map_err(std::io::Error::other)?,
+            ),
+        ];
+
+        for (field_name, serialized) in fields {
+            self.save_to_keyring(&Self::field_key(key, field_name), &serialized)?;
+        }
+
+        if let Err(err) = self.keyring_store.delete(KEYRING_SERVICE, key) {
+            warn!("failed to remove legacy CLI auth from keyring: {err}");
+        }
+        Ok(())
+    }
+
+    fn load_windows_auth_from_keyring(&self, key: &str) -> std::io::Result<Option<AuthDotJson>> {
+        fn load_auth_field_from_keyring<T>(
+            keyring_store: &dyn KeyringStore,
+            key: &str,
+        ) -> std::io::Result<Option<T>>
+        where
+            T: DeserializeOwned,
+        {
+            match keyring_store.load(KEYRING_SERVICE, key) {
+                Ok(Some(serialized)) => {
+                    serde_json::from_str(&serialized).map(Some).map_err(|err| {
+                        std::io::Error::other(format!(
+                            "failed to deserialize CLI auth field from keyring: {err}"
+                        ))
+                    })
+                }
+                Ok(None) => Ok(None),
+                Err(error) => Err(std::io::Error::other(format!(
+                    "failed to load CLI auth from keyring: {}",
+                    error.message()
+                ))),
+            }
+        }
+
+        let auth_mode = load_auth_field_from_keyring::<Option<AuthMode>>(
+            self.keyring_store.as_ref(),
+            &Self::field_key(key, AUTH_MODE_FIELD),
+        )?;
+        let openai_api_key = load_auth_field_from_keyring::<Option<String>>(
+            self.keyring_store.as_ref(),
+            &Self::field_key(key, OPENAI_API_KEY_FIELD),
+        )?;
+        let tokens = load_auth_field_from_keyring::<Option<TokenData>>(
+            self.keyring_store.as_ref(),
+            &Self::field_key(key, TOKENS_FIELD),
+        )?;
+        let last_refresh = load_auth_field_from_keyring::<Option<DateTime<Utc>>>(
+            self.keyring_store.as_ref(),
+            &Self::field_key(key, LAST_REFRESH_FIELD),
+        )?;
+
+        if auth_mode.is_none()
+            && openai_api_key.is_none()
+            && tokens.is_none()
+            && last_refresh.is_none()
+        {
+            return Ok(None);
+        }
+
+        Ok(Some(AuthDotJson {
+            auth_mode: auth_mode.flatten(),
+            openai_api_key: openai_api_key.flatten(),
+            tokens: tokens.flatten(),
+            last_refresh: last_refresh.flatten(),
+        }))
+    }
+
+    fn delete_windows_auth_from_keyring(&self, key: &str) -> std::io::Result<bool> {
+        let field_keys = [
+            Self::field_key(key, AUTH_MODE_FIELD),
+            Self::field_key(key, OPENAI_API_KEY_FIELD),
+            Self::field_key(key, TOKENS_FIELD),
+            Self::field_key(key, LAST_REFRESH_FIELD),
+            key.to_string(),
+        ];
+        let mut removed = false;
+
+        for field_key in field_keys {
+            removed |= self
+                .keyring_store
+                .delete(KEYRING_SERVICE, &field_key)
+                .map_err(|err| {
+                    std::io::Error::other(format!("failed to delete auth from keyring: {err}"))
+                })?;
+        }
+
+        Ok(removed)
+    }
 }
 
 impl AuthStorageBackend for KeyringAuthStorage {
     fn load(&self) -> std::io::Result<Option<AuthDotJson>> {
         let key = compute_store_key(&self.codex_home)?;
-        self.load_from_keyring(&key)
+        if cfg!(windows) {
+            self.load_windows_auth_from_keyring(&key)
+        } else {
+            self.load_from_keyring(&key)
+        }
     }
 
     fn save(&self, auth: &AuthDotJson) -> std::io::Result<()> {
         let key = compute_store_key(&self.codex_home)?;
-        // Simpler error mapping per style: prefer method reference over closure
-        let serialized = serde_json::to_string(auth).map_err(std::io::Error::other)?;
-        self.save_to_keyring(&key, &serialized)?;
+        if cfg!(windows) {
+            self.save_windows_auth_to_keyring(&key, auth)?;
+        } else {
+            let serialized = serde_json::to_string(auth).map_err(std::io::Error::other)?;
+            self.save_to_keyring(&key, &serialized)?;
+        }
         if let Err(err) = delete_file_if_exists(&self.codex_home) {
             warn!("failed to remove CLI auth fallback file: {err}");
         }
@@ -196,12 +325,15 @@ impl AuthStorageBackend for KeyringAuthStorage {
 
     fn delete(&self) -> std::io::Result<bool> {
         let key = compute_store_key(&self.codex_home)?;
-        let keyring_removed = self
-            .keyring_store
-            .delete(KEYRING_SERVICE, &key)
-            .map_err(|err| {
-                std::io::Error::other(format!("failed to delete auth from keyring: {err}"))
-            })?;
+        let keyring_removed = if cfg!(windows) {
+            self.delete_windows_auth_from_keyring(&key)?
+        } else {
+            self.keyring_store
+                .delete(KEYRING_SERVICE, &key)
+                .map_err(|err| {
+                    std::io::Error::other(format!("failed to delete auth from keyring: {err}"))
+                })?
+        };
         let file_removed = delete_file_if_exists(&self.codex_home)?;
         Ok(keyring_removed || file_removed)
     }

codex-rs/login/src/auth/storage_tests.rs

@@ -126,6 +126,34 @@ where
     Ok(())
 }
 
+fn seed_windows_keyring_with_auth(
+    mock_keyring: &MockKeyringStore,
+    key: &str,
+    auth: &AuthDotJson,
+) -> anyhow::Result<()> {
+    mock_keyring.save(
+        KEYRING_SERVICE,
+        &KeyringAuthStorage::field_key(key, AUTH_MODE_FIELD),
+        &serde_json::to_string(&auth.auth_mode)?,
+    )?;
+    mock_keyring.save(
+        KEYRING_SERVICE,
+        &KeyringAuthStorage::field_key(key, OPENAI_API_KEY_FIELD),
+        &serde_json::to_string(&auth.openai_api_key)?,
+    )?;
+    mock_keyring.save(
+        KEYRING_SERVICE,
+        &KeyringAuthStorage::field_key(key, TOKENS_FIELD),
+        &serde_json::to_string(&auth.tokens)?,
+    )?;
+    mock_keyring.save(
+        KEYRING_SERVICE,
+        &KeyringAuthStorage::field_key(key, LAST_REFRESH_FIELD),
+        &serde_json::to_string(&auth.last_refresh)?,
+    )?;
+    Ok(())
+}
+
 fn assert_keyring_saved_auth_and_removed_fallback(
     mock_keyring: &MockKeyringStore,
     key: &str,
@@ -144,6 +172,44 @@ fn assert_keyring_saved_auth_and_removed_fallback(
     );
 }
 
+fn assert_windows_keyring_saved_auth_and_removed_fallback(
+    mock_keyring: &MockKeyringStore,
+    key: &str,
+    codex_home: &Path,
+    expected: &AuthDotJson,
+) {
+    let auth_mode_key = KeyringAuthStorage::field_key(key, AUTH_MODE_FIELD);
+    let openai_api_key_key = KeyringAuthStorage::field_key(key, OPENAI_API_KEY_FIELD);
+    let tokens_key = KeyringAuthStorage::field_key(key, TOKENS_FIELD);
+    let last_refresh_key = KeyringAuthStorage::field_key(key, LAST_REFRESH_FIELD);
+
+    assert_eq!(
+        mock_keyring.saved_value(&auth_mode_key),
+        Some(serde_json::to_string(&expected.auth_mode).expect("serialize auth_mode")),
+    );
+    assert_eq!(
+        mock_keyring.saved_value(&openai_api_key_key),
+        Some(serde_json::to_string(&expected.openai_api_key).expect("serialize openai_api_key")),
+    );
+    assert_eq!(
+        mock_keyring.saved_value(&tokens_key),
+        Some(serde_json::to_string(&expected.tokens).expect("serialize tokens")),
+    );
+    assert_eq!(
+        mock_keyring.saved_value(&last_refresh_key),
+        Some(serde_json::to_string(&expected.last_refresh).expect("serialize last_refresh")),
+    );
+    assert!(
+        mock_keyring.saved_value(key).is_none(),
+        "legacy whole-auth key should be removed after windows keyring save"
+    );
+    let auth_file = get_auth_file(codex_home);
+    assert!(
+        !auth_file.exists(),
+        "fallback auth.json should be removed after keyring save"
+    );
+}
+
 fn id_token_with_prefix(prefix: &str) -> IdTokenInfo {
     #[derive(Serialize)]
     struct Header {
@@ -275,6 +341,108 @@ fn keyring_auth_storage_delete_removes_keyring_and_file() -> anyhow::Result<()>
     Ok(())
 }
 
+#[test]
+fn keyring_auth_storage_windows_load_combines_split_entries() -> anyhow::Result<()> {
+    let codex_home = tempdir()?;
+    let mock_keyring = MockKeyringStore::default();
+    let storage = KeyringAuthStorage::new(
+        codex_home.path().to_path_buf(),
+        Arc::new(mock_keyring.clone()),
+    );
+    let expected = auth_with_prefix("windows-load");
+    let key = compute_store_key(codex_home.path())?;
+    seed_windows_keyring_with_auth(&mock_keyring, &key, &expected)?;
+
+    let loaded = storage.load_windows_auth_from_keyring(&key)?;
+
+    assert_eq!(Some(expected), loaded);
+    Ok(())
+}
+
+#[test]
+fn keyring_auth_storage_windows_load_ignores_legacy_entry() -> anyhow::Result<()> {
+    let codex_home = tempdir()?;
+    let mock_keyring = MockKeyringStore::default();
+    let storage = KeyringAuthStorage::new(
+        codex_home.path().to_path_buf(),
+        Arc::new(mock_keyring.clone()),
+    );
+    let expected = auth_with_prefix("windows-legacy");
+    let key = compute_store_key(codex_home.path())?;
+    seed_keyring_with_auth(&mock_keyring, || Ok(key.clone()), &expected)?;
+
+    let loaded = storage.load_windows_auth_from_keyring(&key)?;
+
+    assert_eq!(None, loaded);
+    Ok(())
+}
+
+#[test]
+fn keyring_auth_storage_windows_save_persists_split_entries() -> anyhow::Result<()> {
+    let codex_home = tempdir()?;
+    let mock_keyring = MockKeyringStore::default();
+    let storage = KeyringAuthStorage::new(
+        codex_home.path().to_path_buf(),
+        Arc::new(mock_keyring.clone()),
+    );
+    let auth_file = get_auth_file(codex_home.path());
+    std::fs::write(&auth_file, "stale")?;
+    let auth = auth_with_prefix("windows-save");
+    let key = compute_store_key(codex_home.path())?;
+    mock_keyring.save(KEYRING_SERVICE, &key, "legacy-auth")?;
+
+    storage.save_windows_auth_to_keyring(&key, &auth)?;
+    if let Err(err) = delete_file_if_exists(codex_home.path()) {
+        panic!("failed to remove fallback auth file in test: {err}");
+    }
+
+    assert_windows_keyring_saved_auth_and_removed_fallback(
+        &mock_keyring,
+        &key,
+        codex_home.path(),
+        &auth,
+    );
+    Ok(())
+}
+
+#[test]
+fn keyring_auth_storage_windows_delete_removes_split_entries_and_file() -> anyhow::Result<()> {
+    let codex_home = tempdir()?;
+    let mock_keyring = MockKeyringStore::default();
+    let storage = KeyringAuthStorage::new(
+        codex_home.path().to_path_buf(),
+        Arc::new(mock_keyring.clone()),
+    );
+    let key = compute_store_key(codex_home.path())?;
+    let auth = auth_with_prefix("windows-delete");
+    seed_windows_keyring_with_auth(&mock_keyring, &key, &auth)?;
+    mock_keyring.save(KEYRING_SERVICE, &key, "legacy-auth")?;
+    let auth_file = get_auth_file(codex_home.path());
+    std::fs::write(&auth_file, "stale")?;
+
+    let removed = storage.delete_windows_auth_from_keyring(&key)?;
+    let file_removed = delete_file_if_exists(codex_home.path())?;
+
+    assert!(removed, "delete should report removal");
+    assert!(file_removed, "fallback auth.json should be removed");
+    assert!(!mock_keyring.contains(&KeyringAuthStorage::field_key(
+        key.as_str(),
+        AUTH_MODE_FIELD
+    )));
+    assert!(!mock_keyring.contains(&KeyringAuthStorage::field_key(
+        key.as_str(),
+        OPENAI_API_KEY_FIELD,
+    )));
+    assert!(!mock_keyring.contains(&KeyringAuthStorage::field_key(key.as_str(), TOKENS_FIELD)));
+    assert!(!mock_keyring.contains(&KeyringAuthStorage::field_key(
+        key.as_str(),
+        LAST_REFRESH_FIELD,
+    )));
+    assert!(!mock_keyring.contains(&key));
+    assert!(!auth_file.exists());
+    Ok(())
+}
+
 #[test]
 fn auto_auth_storage_load_prefers_keyring_value() -> anyhow::Result<()> {
     let codex_home = tempdir()?;