diff --git a/codex-rs/core/tests/common/responses.rs b/codex-rs/core/tests/common/responses.rs
index 710d03fc7f..8a68b3e938 100644
--- a/codex-rs/core/tests/common/responses.rs
+++ b/codex-rs/core/tests/common/responses.rs
@@ -509,12 +509,17 @@ pub fn ev_apply_patch_function_call(call_id: &str, patch: &str) -> Value {
 }
 
 pub fn ev_shell_command_call(call_id: &str, command: &str) -> Value {
-    let args = serde_json::json!({ "command": command });
+    let args = serde_json::json!({ "command": command, "login": false });
     ev_shell_command_call_with_args(call_id, &args)
 }
 
 pub fn ev_shell_command_call_with_args(call_id: &str, args: &serde_json::Value) -> Value {
-    let arguments = serde_json::to_string(args).expect("serialize shell command arguments");
+    let mut args = args.clone();
+    if let serde_json::Value::Object(map) = &mut args {
+        map.entry("login".to_string())
+            .or_insert_with(|| serde_json::Value::Bool(false));
+    }
+    let arguments = serde_json::to_string(&args).expect("serialize shell command arguments");
     ev_function_call(call_id, "shell_command", &arguments)
 }
 
@@ -527,17 +532,18 @@ pub fn ev_apply_patch_shell_call(call_id: &str, patch: &str) -> Value {
 
 pub fn ev_apply_patch_shell_call_via_heredoc(call_id: &str, patch: &str) -> Value {
     let script = format!("apply_patch <<'EOF'\n{patch}\nEOF\n");
-    let args = serde_json::json!({ "command": ["bash", "-lc", script] });
+    let args = serde_json::json!({ "command": ["bash", "-c", script] });
     let arguments = serde_json::to_string(&args).expect("serialize apply_patch arguments");
 
     ev_function_call(call_id, "shell", &arguments)
 }
 
 pub fn ev_apply_patch_shell_command_call_via_heredoc(call_id: &str, patch: &str) -> Value {
-    let args = serde_json::json!({ "command": format!("apply_patch <<'EOF'\n{patch}\nEOF\n") });
-    let arguments = serde_json::to_string(&args).expect("serialize apply_patch arguments");
-
-    ev_function_call(call_id, "shell_command", &arguments)
+    let args = serde_json::json!({
+        "command": format!("apply_patch <<'EOF'\n{patch}\nEOF\n"),
+        "login": false,
+    });
+    ev_shell_command_call_with_args(call_id, &args)
 }
 
 pub fn sse_failed(id: &str, code: &str, message: &str) -> String {
diff --git a/codex-rs/core/tests/suite/approvals.rs b/codex-rs/core/tests/suite/approvals.rs
index 51f1c31f17..cda844e9e5 100644
--- a/codex-rs/core/tests/suite/approvals.rs
+++ b/codex-rs/core/tests/suite/approvals.rs
@@ -30,9 +30,11 @@ use pretty_assertions::assert_eq;
 use regex_lite::Regex;
 use serde_json::Value;
 use serde_json::json;
-use std::env;
 use std::fs;
+use std::path::Path;
 use std::path::PathBuf;
+use std::sync::OnceLock;
+use tempfile::Builder;
 use wiremock::Mock;
 use wiremock::MockServer;
 use wiremock::ResponseTemplate;
@@ -45,6 +47,52 @@ enum TargetPath {
     OutsideWorkspace(&'static str),
 }
 
+fn candidate_is_outside_tmp(candidate: &Path) -> bool {
+    let temp_dir = std::env::temp_dir();
+    if candidate.starts_with(&temp_dir) {
+        return false;
+    }
+    if cfg!(unix) && candidate.starts_with(Path::new("/tmp")) {
+        return false;
+    }
+    if let Some(tmpdir) = std::env::var_os("TMPDIR") {
+        let tmpdir = PathBuf::from(tmpdir);
+        if candidate.starts_with(&tmpdir) {
+            return false;
+        }
+    }
+    true
+}
+
+fn outside_workspace_root() -> &'static PathBuf {
+    static OUTSIDE_ROOT: OnceLock<PathBuf> = OnceLock::new();
+    OUTSIDE_ROOT.get_or_init(|| {
+        let mut candidates = Vec::new();
+        if cfg!(unix) {
+            candidates.push(PathBuf::from("/var/tmp"));
+        }
+        if let Some(home) = std::env::var_os("HOME").or_else(|| std::env::var_os("USERPROFILE")) {
+            candidates.push(PathBuf::from(home));
+        }
+        for candidate in candidates {
+            if !candidate.is_dir() || !candidate_is_outside_tmp(&candidate) {
+                continue;
+            }
+            if let Ok(dir) = Builder::new()
+                .prefix("codex-outside-")
+                .tempdir_in(&candidate)
+            {
+                return dir.keep();
+            }
+        }
+        Builder::new()
+            .prefix("codex-outside-")
+            .tempdir()
+            .expect("create outside workspace temp dir")
+            .keep()
+    })
+}
+
 impl TargetPath {
     fn resolve_for_patch(self, test: &TestCodex) -> (PathBuf, String) {
         match self {
@@ -53,9 +101,7 @@ impl TargetPath {
                 (path, name.to_string())
             }
             TargetPath::OutsideWorkspace(name) => {
-                let path = env::current_dir()
-                    .expect("current dir should be available")
-                    .join(name);
+                let path = outside_workspace_root().join(name);
                 (path.clone(), path.display().to_string())
             }
         }
@@ -187,6 +233,7 @@ fn shell_event(
 ) -> Result<Value> {
     let mut args = json!({
         "command": command,
+        "login": false,
         "timeout_ms": timeout_ms,
     });
     if sandbox_permissions.requires_escalated_permissions() {
diff --git a/codex-rs/core/tests/suite/shell_serialization.rs b/codex-rs/core/tests/suite/shell_serialization.rs
index 6969b6533d..1527946f5c 100644
--- a/codex-rs/core/tests/suite/shell_serialization.rs
+++ b/codex-rs/core/tests/suite/shell_serialization.rs
@@ -49,6 +49,7 @@ fn shell_responses(
             let command = shlex::try_join(command)?;
             let parameters = json!({
                 "command": command,
+                "login": false,
                 "timeout_ms": 2_000,
             });
             Ok(vec![
diff --git a/codex-rs/core/tests/suite/unified_exec.rs b/codex-rs/core/tests/suite/unified_exec.rs
index 2e2fd34e67..96e9ae3643 100644
--- a/codex-rs/core/tests/suite/unified_exec.rs
+++ b/codex-rs/core/tests/suite/unified_exec.rs
@@ -46,6 +46,15 @@ fn extract_output_text(item: &Value) -> Option<&str> {
     })
 }
 
+fn exec_command_args(mut args: Value) -> Value {
+    if let Value::Object(map) = &mut args
+        && map.contains_key("cmd")
+    {
+        map.entry("login".to_string()).or_insert(Value::Bool(false));
+    }
+    args
+}
+
 #[derive(Debug)]
 struct ParsedUnifiedExecOutput {
     chunk_id: Option<String>,
@@ -171,10 +180,10 @@ async fn unified_exec_intercepts_apply_patch_exec_command() -> Result<()> {
         "*** Begin Patch\n*** Add File: uexec_apply.txt\n+hello from unified exec\n*** End Patch";
     let command = format!("apply_patch <<'EOF'\n{patch}\nEOF\n");
     let call_id = "uexec-apply-patch";
-    let args = json!({
+    let args = exec_command_args(json!({
         "cmd": command,
         "yield_time_ms": 250,
-    });
+    }));
 
     let responses = vec![
         sse(vec![
@@ -299,11 +308,11 @@ async fn unified_exec_emits_exec_command_begin_event() -> Result<()> {
     } = builder.build(&server).await?;
 
     let call_id = "uexec-begin-event";
-    let args = json!({
+    let args = exec_command_args(json!({
         "shell": "bash".to_string(),
         "cmd": "/bin/echo hello unified exec".to_string(),
         "yield_time_ms": 250,
-    });
+    }));
 
     let responses = vec![
         sse(vec![
@@ -342,7 +351,7 @@ async fn unified_exec_emits_exec_command_begin_event() -> Result<()> {
     })
     .await;
 
-    assert_command(&begin_event.command, "-lc", "/bin/echo hello unified exec");
+    assert_command(&begin_event.command, "-c", "/bin/echo hello unified exec");
 
     assert_eq!(begin_event.cwd, cwd.path());
 
@@ -374,11 +383,11 @@ async fn unified_exec_resolves_relative_workdir() -> Result<()> {
     std::fs::create_dir_all(cwd.path().join(&workdir_rel))?;
 
     let call_id = "uexec-workdir-relative";
-    let args = json!({
+    let args = exec_command_args(json!({
         "cmd": "pwd",
         "yield_time_ms": 250,
         "workdir": workdir_rel.to_string_lossy().to_string(),
-    });
+    }));
 
     let responses = vec![
         sse(vec![
@@ -452,11 +461,11 @@ async fn unified_exec_respects_workdir_override() -> Result<()> {
     std::fs::create_dir_all(&workdir)?;
 
     let call_id = "uexec-workdir";
-    let args = json!({
+    let args = exec_command_args(json!({
         "cmd": "pwd",
         "yield_time_ms": 250,
         "workdir": workdir.to_string_lossy().to_string(),
-    });
+    }));
 
     let responses = vec![
         sse(vec![
@@ -528,16 +537,16 @@ async fn unified_exec_emits_exec_command_end_event() -> Result<()> {
     } = builder.build(&server).await?;
 
     let call_id = "uexec-end-event";
-    let args = json!({
+    let args = exec_command_args(json!({
         "cmd": "/bin/echo END-EVENT".to_string(),
         "yield_time_ms": 250,
-    });
+    }));
     let poll_call_id = "uexec-end-event-poll";
-    let poll_args = json!({
+    let poll_args = exec_command_args(json!({
         "chars": "",
         "session_id": 1000,
         "yield_time_ms": 250,
-    });
+    }));
 
     let responses = vec![
         sse(vec![
@@ -615,10 +624,10 @@ async fn unified_exec_emits_output_delta_for_exec_command() -> Result<()> {
     } = builder.build(&server).await?;
 
     let call_id = "uexec-delta-1";
-    let args = json!({
+    let args = exec_command_args(json!({
         "cmd": "printf 'HELLO-UEXEC'",
         "yield_time_ms": 1000,
-    });
+    }));
 
     let responses = vec![
         sse(vec![
@@ -688,10 +697,10 @@ async fn unified_exec_full_lifecycle_with_background_end_event() -> Result<()> {
 
     let call_id = "uexec-full-lifecycle";
     // This timing force the long-standing PTY
-    let args = json!({
+    let args = exec_command_args(json!({
         "cmd": "sleep 0.5; printf 'HELLO-FULL-LIFECYCLE'",
         "yield_time_ms": 1000,
-    });
+    }));
 
     let responses = vec![
         sse(vec![
@@ -794,17 +803,17 @@ async fn unified_exec_emits_terminal_interaction_for_write_stdin() -> Result<()>
     } = builder.build(&server).await?;
 
     let open_call_id = "uexec-open";
-    let open_args = json!({
+    let open_args = exec_command_args(json!({
         "cmd": "/bin/bash -i",
         "yield_time_ms": 200,
-    });
+    }));
 
     let stdin_call_id = "uexec-stdin-delta";
-    let stdin_args = json!({
+    let stdin_args = exec_command_args(json!({
         "chars": "echo WSTDIN-MARK\\n",
         "session_id": 1000,
         "yield_time_ms": 800,
-    });
+    }));
 
     let responses = vec![
         sse(vec![
@@ -893,33 +902,33 @@ async fn unified_exec_terminal_interaction_captures_delayed_output() -> Result<(
     } = builder.build(&server).await?;
 
     let open_call_id = "uexec-delayed-open";
-    let open_args = json!({
+    let open_args = exec_command_args(json!({
         "cmd": "sleep 3 && echo MARKER1 && sleep 3 && echo MARKER2",
         "yield_time_ms": 10,
-    });
+    }));
 
     // Poll stdin three times: first for no output, second after the first marker,
     // and a final long poll to capture the second marker.
     let first_poll_call_id = "uexec-delayed-poll-1";
-    let first_poll_args = json!({
+    let first_poll_args = exec_command_args(json!({
         "chars": "",
         "session_id": 1000,
         "yield_time_ms": 10,
-    });
+    }));
 
     let second_poll_call_id = "uexec-delayed-poll-2";
-    let second_poll_args = json!({
+    let second_poll_args = exec_command_args(json!({
         "chars": "",
         "session_id": 1000,
         "yield_time_ms": 4000,
-    });
+    }));
 
     let third_poll_call_id = "uexec-delayed-poll-3";
-    let third_poll_args = json!({
+    let third_poll_args = exec_command_args(json!({
         "chars": "",
         "session_id": 1000,
         "yield_time_ms": 6000,
-    });
+    }));
 
     let responses = vec![
         sse(vec![
@@ -1083,18 +1092,18 @@ async fn unified_exec_emits_one_begin_and_one_end_event() -> Result<()> {
     } = builder.build(&server).await?;
 
     let open_call_id = "uexec-open-session";
-    let open_args = json!({
+    let open_args = exec_command_args(json!({
         "shell": "bash".to_string(),
         "cmd": "sleep 0.1".to_string(),
         "yield_time_ms": 10,
-    });
+    }));
 
     let poll_call_id = "uexec-poll-empty";
-    let poll_args = json!({
+    let poll_args = exec_command_args(json!({
         "chars": "",
         "session_id": 1000,
         "yield_time_ms": 150,
-    });
+    }));
 
     let responses = vec![
         sse(vec![
@@ -1166,7 +1175,7 @@ async fn unified_exec_emits_one_begin_and_one_end_event() -> Result<()> {
 
     let open_event = &begin_events[0];
 
-    assert_command(&open_event.command, "-lc", "sleep 0.1");
+    assert_command(&open_event.command, "-c", "sleep 0.1");
 
     assert!(
         open_event.interaction_input.is_none(),
@@ -1199,11 +1208,11 @@ async fn exec_command_reports_chunk_and_exit_metadata() -> Result<()> {
     } = builder.build(&server).await?;
 
     let call_id = "uexec-metadata";
-    let args = serde_json::json!({
+    let args = exec_command_args(serde_json::json!({
         "cmd": "printf 'token one token two token three token four token five token six token seven'",
         "yield_time_ms": 500,
         "max_output_tokens": 6,
-    });
+    }));
 
     let responses = vec![
         sse(vec![
@@ -1306,10 +1315,10 @@ async fn unified_exec_respects_early_exit_notifications() -> Result<()> {
     } = builder.build(&server).await?;
 
     let call_id = "uexec-early-exit";
-    let args = serde_json::json!({
+    let args = exec_command_args(serde_json::json!({
         "cmd": "sleep 0.05",
         "yield_time_ms": 31415,
-    });
+    }));
 
     let responses = vec![
         sse(vec![
@@ -1401,20 +1410,20 @@ async fn write_stdin_returns_exit_metadata_and_clears_session() -> Result<()> {
     let send_call_id = "uexec-cat-send";
     let exit_call_id = "uexec-cat-exit";
 
-    let start_args = serde_json::json!({
+    let start_args = exec_command_args(serde_json::json!({
         "cmd": "/bin/cat",
         "yield_time_ms": 500,
-    });
-    let send_args = serde_json::json!({
+    }));
+    let send_args = exec_command_args(serde_json::json!({
         "chars": "hello unified exec\n",
         "session_id": 1000,
         "yield_time_ms": 500,
-    });
-    let exit_args = serde_json::json!({
+    }));
+    let exit_args = exec_command_args(serde_json::json!({
         "chars": "\u{0004}",
         "session_id": 1000,
         "yield_time_ms": 500,
-    });
+    }));
 
     let responses = vec![
         sse(vec![
@@ -1560,24 +1569,24 @@ async fn unified_exec_emits_end_event_when_session_dies_via_stdin() -> Result<()
     } = builder.build(&server).await?;
 
     let start_call_id = "uexec-end-on-exit-start";
-    let start_args = serde_json::json!({
+    let start_args = exec_command_args(serde_json::json!({
         "cmd": "/bin/cat",
         "yield_time_ms": 200,
-    });
+    }));
 
     let echo_call_id = "uexec-end-on-exit-echo";
-    let echo_args = serde_json::json!({
+    let echo_args = exec_command_args(serde_json::json!({
         "chars": "bye-END\n",
         "session_id": 1000,
         "yield_time_ms": 300,
-    });
+    }));
 
     let exit_call_id = "uexec-end-on-exit";
-    let exit_args = serde_json::json!({
+    let exit_args = exec_command_args(serde_json::json!({
         "chars": "\u{0004}",
         "session_id": 1000,
         "yield_time_ms": 500,
-    });
+    }));
 
     let responses = vec![
         sse(vec![
@@ -1670,10 +1679,10 @@ async fn unified_exec_closes_long_running_session_at_turn_end() -> Result<()> {
 
     let call_id = "uexec-long-running";
     let command = format!("printf '%s' $$ > '{pid_path_str}' && exec sleep 3000");
-    let args = json!({
+    let args = exec_command_args(json!({
         "cmd": command,
         "yield_time_ms": 250,
-    });
+    }));
 
     let responses = vec![
         sse(vec![
@@ -1769,17 +1778,17 @@ async fn unified_exec_reuses_session_via_stdin() -> Result<()> {
     } = builder.build(&server).await?;
 
     let first_call_id = "uexec-start";
-    let first_args = serde_json::json!({
+    let first_args = exec_command_args(serde_json::json!({
         "cmd": "/bin/cat",
         "yield_time_ms": 200,
-    });
+    }));
 
     let second_call_id = "uexec-stdin";
-    let second_args = serde_json::json!({
+    let second_args = exec_command_args(serde_json::json!({
         "chars": "hello unified exec\n",
         "session_id": 1000,
         "yield_time_ms": 500,
-    });
+    }));
 
     let responses = vec![
         sse(vec![
@@ -1900,17 +1909,17 @@ PY
 "#;
 
     let first_call_id = "uexec-lag-start";
-    let first_args = serde_json::json!({
+    let first_args = exec_command_args(serde_json::json!({
         "cmd": script,
         "yield_time_ms": 25,
-    });
+    }));
 
     let second_call_id = "uexec-lag-poll";
-    let second_args = serde_json::json!({
+    let second_args = exec_command_args(serde_json::json!({
         "chars": "",
         "session_id": 1000,
         "yield_time_ms": 2_000,
-    });
+    }));
 
     let responses = vec![
         sse(vec![
@@ -2011,17 +2020,17 @@ async fn unified_exec_timeout_and_followup_poll() -> Result<()> {
     } = builder.build(&server).await?;
 
     let first_call_id = "uexec-timeout";
-    let first_args = serde_json::json!({
+    let first_args = exec_command_args(serde_json::json!({
         "cmd": "sleep 0.5; echo ready",
         "yield_time_ms": 10,
-    });
+    }));
 
     let second_call_id = "uexec-poll";
-    let second_args = serde_json::json!({
+    let second_args = exec_command_args(serde_json::json!({
         "chars": "",
         "session_id": 1000,
         "yield_time_ms": 800,
-    });
+    }));
 
     let responses = vec![
         sse(vec![
@@ -2123,11 +2132,11 @@ PY
 "#;
 
     let call_id = "uexec-large-output";
-    let args = serde_json::json!({
+    let args = exec_command_args(serde_json::json!({
         "cmd": script,
         "max_output_tokens": 100,
         "yield_time_ms": 500,
-    });
+    }));
 
     let responses = vec![
         sse(vec![
@@ -2202,10 +2211,10 @@ async fn unified_exec_runs_under_sandbox() -> Result<()> {
     } = builder.build(&server).await?;
 
     let call_id = "uexec";
-    let args = serde_json::json!({
+    let args = exec_command_args(serde_json::json!({
         "cmd": "echo 'hello'",
         "yield_time_ms": 500,
-    });
+    }));
 
     let responses = vec![
         sse(vec![
@@ -2282,17 +2291,17 @@ async fn unified_exec_python_prompt_under_seatbelt() -> Result<()> {
     } = builder.build(&server).await?;
 
     let startup_call_id = "uexec-python-seatbelt";
-    let startup_args = serde_json::json!({
+    let startup_args = exec_command_args(serde_json::json!({
         "cmd": format!("{} -i", python.display()),
         "yield_time_ms": 1_500,
-    });
+    }));
 
     let exit_call_id = "uexec-python-exit";
-    let exit_args = serde_json::json!({
+    let exit_args = exec_command_args(serde_json::json!({
         "chars": "exit()\n",
         "session_id": 1000,
         "yield_time_ms": 1_500,
-    });
+    }));
 
     let responses = vec![
         sse(vec![
@@ -2396,9 +2405,9 @@ async fn unified_exec_runs_on_all_platforms() -> Result<()> {
     } = builder.build(&server).await?;
 
     let call_id = "uexec";
-    let args = serde_json::json!({
+    let args = exec_command_args(serde_json::json!({
         "cmd": "echo 'hello crossplat'",
-    });
+    }));
 
     let responses = vec![
         sse(vec![
@@ -2472,17 +2481,17 @@ async fn unified_exec_prunes_exited_sessions_first() -> Result<()> {
     const FILLER_SESSIONS: i32 = MAX_SESSIONS_FOR_TEST - 1;
 
     let keep_call_id = "uexec-prune-keep";
-    let keep_args = serde_json::json!({
+    let keep_args = exec_command_args(serde_json::json!({
         "cmd": "/bin/cat",
         "yield_time_ms": 250,
-    });
+    }));
 
     let prune_call_id = "uexec-prune-target";
     // Give the sleeper time to exit before the filler sessions trigger pruning.
-    let prune_args = serde_json::json!({
+    let prune_args = exec_command_args(serde_json::json!({
         "cmd": "sleep 1",
         "yield_time_ms": 1_250,
-    });
+    }));
 
     let mut events = vec![ev_response_created("resp-prune-1")];
     events.push(ev_function_call(
@@ -2497,10 +2506,10 @@ async fn unified_exec_prunes_exited_sessions_first() -> Result<()> {
     ));
 
     for idx in 0..FILLER_SESSIONS {
-        let filler_args = serde_json::json!({
+        let filler_args = exec_command_args(serde_json::json!({
             "cmd": format!("echo filler {idx}"),
             "yield_time_ms": 250,
-        });
+        }));
         let call_id = format!("uexec-prune-fill-{idx}");
         events.push(ev_function_call(
             &call_id,
@@ -2510,11 +2519,11 @@ async fn unified_exec_prunes_exited_sessions_first() -> Result<()> {
     }
 
     let keep_write_call_id = "uexec-prune-keep-write";
-    let keep_write_args = serde_json::json!({
+    let keep_write_args = exec_command_args(serde_json::json!({
         "chars": "still alive\n",
         "session_id": 1000,
         "yield_time_ms": 500,
-    });
+    }));
     events.push(ev_function_call(
         keep_write_call_id,
         "write_stdin",
@@ -2522,11 +2531,11 @@ async fn unified_exec_prunes_exited_sessions_first() -> Result<()> {
     ));
 
     let probe_call_id = "uexec-prune-probe";
-    let probe_args = serde_json::json!({
+    let probe_args = exec_command_args(serde_json::json!({
         "chars": "should fail\n",
         "session_id": 1001,
         "yield_time_ms": 500,
-    });
+    }));
     events.push(ev_function_call(
         probe_call_id,
         "write_stdin",