feat: wire ephemeral in codex exec (#10758)

codex-rs/README.md

@@ -51,6 +51,7 @@ You can enable notifications by configuring a script that is run whenever the ag
 ### `codex exec` to run Codex programmatically/non-interactively
 
 To run Codex non-interactively, run `codex exec PROMPT` (you can also pass the prompt via `stdin`) and Codex will work on your task until it decides that it is done and exits. Output is printed to the terminal directly. You can set the `RUST_LOG` environment variable to see more about what's going on.
+Use `codex exec --ephemeral ...` to run without persisting session rollout files to disk.
 
 ### Experimenting with the Codex Sandbox
 

codex-rs/exec/src/cli.rs

@@ -71,6 +71,10 @@ pub struct Cli {
     #[arg(long = "add-dir", value_name = "DIR", value_hint = clap::ValueHint::DirPath)]
     pub add_dir: Vec<PathBuf>,
 
+    /// Run without persisting session files to disk.
+    #[arg(long = "ephemeral", global = true, default_value_t = false)]
+    pub ephemeral: bool,
+
     /// Path to a JSON Schema file describing the model's final response shape.
     #[arg(long = "output-schema", value_name = "FILE")]
     pub output_schema: Option<PathBuf>,
@@ -262,9 +266,11 @@ mod tests {
             "gpt-5.2-codex",
             "--dangerously-bypass-approvals-and-sandbox",
             "--skip-git-repo-check",
+            "--ephemeral",
             PROMPT,
         ]);
 
+        assert!(cli.ephemeral);
         let Some(Command::Resume(args)) = cli.command else {
             panic!("expected resume command");
         };

codex-rs/exec/src/lib.rs

@@ -103,6 +103,7 @@ pub async fn run_main(cli: Cli, codex_linux_sandbox_exe: Option<PathBuf>) -> any
         cwd,
         skip_git_repo_check,
         add_dir,
+        ephemeral,
         color,
         last_message_file,
         json: json_mode,
@@ -254,7 +255,7 @@ pub async fn run_main(cli: Cli, codex_linux_sandbox_exe: Option<PathBuf>) -> any
         include_apply_patch_tool: None,
         show_raw_agent_reasoning: oss.then_some(true),
         tools_web_search_request: None,
-        ephemeral: None,
+        ephemeral: ephemeral.then_some(true),
         additional_writable_roots: add_dir,
     };
 

codex-rs/exec/tests/suite/ephemeral.rs

@@ -0,0 +1,55 @@
+#![cfg(not(target_os = "windows"))]
+#![allow(clippy::expect_used, clippy::unwrap_used)]
+
+use codex_utils_cargo_bin::find_resource;
+use core_test_support::test_codex_exec::test_codex_exec;
+use walkdir::WalkDir;
+
+fn session_rollout_count(home_path: &std::path::Path) -> usize {
+    let sessions_dir = home_path.join("sessions");
+    if !sessions_dir.exists() {
+        return 0;
+    }
+
+    WalkDir::new(sessions_dir)
+        .into_iter()
+        .filter_map(Result::ok)
+        .filter(|entry| entry.file_type().is_file())
+        .filter(|entry| entry.file_name().to_string_lossy().ends_with(".jsonl"))
+        .count()
+}
+
+#[test]
+fn persists_rollout_file_by_default() -> anyhow::Result<()> {
+    let test = test_codex_exec();
+    let fixture = find_resource!("tests/fixtures/cli_responses_fixture.sse")?;
+
+    test.cmd()
+        .env("CODEX_RS_SSE_FIXTURE", &fixture)
+        .env("OPENAI_BASE_URL", "http://unused.local")
+        .arg("--skip-git-repo-check")
+        .arg("default persistence behavior")
+        .assert()
+        .code(0);
+
+    assert_eq!(session_rollout_count(test.home_path()), 1);
+    Ok(())
+}
+
+#[test]
+fn does_not_persist_rollout_file_in_ephemeral_mode() -> anyhow::Result<()> {
+    let test = test_codex_exec();
+    let fixture = find_resource!("tests/fixtures/cli_responses_fixture.sse")?;
+
+    test.cmd()
+        .env("CODEX_RS_SSE_FIXTURE", &fixture)
+        .env("OPENAI_BASE_URL", "http://unused.local")
+        .arg("--skip-git-repo-check")
+        .arg("--ephemeral")
+        .arg("ephemeral behavior")
+        .assert()
+        .code(0);
+
+    assert_eq!(session_rollout_count(test.home_path()), 0);
+    Ok(())
+}

codex-rs/exec/tests/suite/mod.rs

@@ -2,6 +2,7 @@
 mod add_dir;
 mod apply_patch;
 mod auth_env;
+mod ephemeral;
 mod originator;
 mod output_schema;
 mod resume;