hint for codex resume on tui exit (#3757)

<img width="931" height="438" alt="Screenshot 2025-09-16 at 4 25 19 PM"
src="https://github.com/user-attachments/assets/ccfb8df1-feaf-45b4-8f7f-56100de916d5"
/>

codex-rs/Cargo.lock

@@ -929,6 +929,7 @@ dependencies = [
  "libc",
  "mcp-types",
  "once_cell",
+ "owo-colors",
  "path-clean",
  "pathdiff",
  "pretty_assertions",

codex-rs/cli/src/main.rs

@@ -177,8 +177,11 @@ async fn cli_main(codex_linux_sandbox_exe: Option<PathBuf>) -> anyhow::Result<()
                 root_config_overrides.clone(),
             );
             let usage = codex_tui::run_main(interactive, codex_linux_sandbox_exe).await?;
-            if !usage.is_zero() {
-                println!("{}", codex_core::protocol::FinalOutput::from(usage));
+            if !usage.token_usage.is_zero() {
+                println!(
+                    "{}",
+                    codex_core::protocol::FinalOutput::from(usage.token_usage)
+                );
             }
         }
         Some(Subcommand::Exec(mut exec_cli)) => {

codex-rs/tui/Cargo.toml

@@ -85,6 +85,7 @@ unicode-segmentation = "1.12.0"
 unicode-width = "0.1"
 url = "2"
 pathdiff = "0.2"
+owo-colors = "4.2.0"
 
 [target.'cfg(unix)'.dependencies]
 libc = "0.2"

codex-rs/tui/src/app.rs

@@ -15,6 +15,7 @@ use codex_core::config::persist_model_selection;
 use codex_core::model_family::find_family_for_model;
 use codex_core::protocol::TokenUsage;
 use codex_core::protocol_config_types::ReasoningEffort as ReasoningEffortConfig;
+use codex_protocol::mcp_protocol::ConversationId;
 use color_eyre::eyre::Result;
 use color_eyre::eyre::WrapErr;
 use crossterm::event::KeyCode;
@@ -33,6 +34,12 @@ use tokio::select;
 use tokio::sync::mpsc::unbounded_channel;
 // use uuid::Uuid;
 
+#[derive(Debug, Clone)]
+pub struct AppExitInfo {
+    pub token_usage: TokenUsage,
+    pub conversation_id: Option<ConversationId>,
+}
+
 pub(crate) struct App {
     pub(crate) server: Arc<ConversationManager>,
     pub(crate) app_event_tx: AppEventSender,
@@ -70,7 +77,7 @@ impl App {
         initial_prompt: Option<String>,
         initial_images: Vec<PathBuf>,
         resume_selection: ResumeSelection,
-    ) -> Result<TokenUsage> {
+    ) -> Result<AppExitInfo> {
         use tokio_stream::StreamExt;
         let (app_event_tx, mut app_event_rx) = unbounded_channel();
         let app_event_tx = AppEventSender::new(app_event_tx);
@@ -153,7 +160,10 @@ impl App {
             }
         } {}
         tui.terminal.clear()?;
-        Ok(app.token_usage())
+        Ok(AppExitInfo {
+            token_usage: app.token_usage(),
+            conversation_id: app.chat_widget.conversation_id(),
+        })
     }
 
     pub(crate) async fn handle_tui_event(

codex-rs/tui/src/lib.rs

@@ -4,6 +4,7 @@
 #![deny(clippy::print_stdout, clippy::print_stderr)]
 #![deny(clippy::disallowed_methods)]
 use app::App;
+pub use app::AppExitInfo;
 use codex_core::AuthManager;
 use codex_core::BUILT_IN_OSS_MODEL_PROVIDER_ID;
 use codex_core::CodexAuth;
@@ -86,7 +87,7 @@ use codex_core::internal_storage::InternalStorage;
 pub async fn run_main(
     cli: Cli,
     codex_linux_sandbox_exe: Option<PathBuf>,
-) -> std::io::Result<codex_core::protocol::TokenUsage> {
+) -> std::io::Result<AppExitInfo> {
     let (sandbox_mode, approval_policy) = if cli.full_auto {
         (
             Some(SandboxMode::WorkspaceWrite),
@@ -258,7 +259,7 @@ async fn run_ratatui_app(
     mut internal_storage: InternalStorage,
     active_profile: Option<String>,
     should_show_trust_screen: bool,
-) -> color_eyre::Result<codex_core::protocol::TokenUsage> {
+) -> color_eyre::Result<AppExitInfo> {
     let mut config = config;
     color_eyre::install()?;
 
@@ -370,7 +371,10 @@ async fn run_ratatui_app(
             resume_picker::ResumeSelection::Exit => {
                 restore();
                 session_log::log_session_end();
-                return Ok(codex_core::protocol::TokenUsage::default());
+                return Ok(AppExitInfo {
+                    token_usage: codex_core::protocol::TokenUsage::default(),
+                    conversation_id: None,
+                });
             }
             other => other,
         }

codex-rs/tui/src/main.rs

@@ -3,6 +3,8 @@ use codex_arg0::arg0_dispatch_or_else;
 use codex_common::CliConfigOverrides;
 use codex_tui::Cli;
 use codex_tui::run_main;
+use owo_colors::OwoColorize;
+use supports_color::Stream;
 
 #[derive(Parser, Debug)]
 struct TopCli {
@@ -21,9 +23,21 @@ fn main() -> anyhow::Result<()> {
             .config_overrides
             .raw_overrides
             .splice(0..0, top_cli.config_overrides.raw_overrides);
-        let usage = run_main(inner, codex_linux_sandbox_exe).await?;
-        if !usage.is_zero() {
-            println!("{}", codex_core::protocol::FinalOutput::from(usage));
+        let exit_info = run_main(inner, codex_linux_sandbox_exe).await?;
+        let token_usage = exit_info.token_usage;
+        let conversation_id = exit_info.conversation_id;
+        if !token_usage.is_zero() {
+            println!("{}", codex_core::protocol::FinalOutput::from(token_usage),);
+            if let Some(session_id) = conversation_id {
+                let command = format!("codex resume {session_id}");
+                let prefix = "To continue this session, run ";
+                let suffix = ".";
+                if supports_color::on(Stream::Stdout).is_some() {
+                    println!("{}{}{}", prefix, command.cyan(), suffix);
+                } else {
+                    println!("{prefix}{command}{suffix}");
+                }
+            }
         }
         Ok(())
     })