Expose voice conversations in experimental features (#44331)

## What changed

- Mark `realtime_conversation` as experimental, keeping it disabled by default, and label it “Voice conversations” in `/experimental`.
- Add an announcement directing users to enable the feature, restart Codex, and run `/voice`.
- Hide server-discovered voice entries and the announcement when the client lacks native voice runtime support.

## Testing

Add tests and snapshots for voice discovery and announcement visibility with and without runtime support, and update the experimental features popup snapshot.

GitOrigin-RevId: 709655f3733cb88191eb78b40ac1f67e27c9816e

codex-rs/features/src/lib.rs

@@ -1680,7 +1680,11 @@ pub const FEATURES: &[FeatureSpec] = &[
     FeatureSpec {
         id: Feature::RealtimeConversation,
         key: "realtime_conversation",
-        stage: Stage::Removed,
+        stage: Stage::Experimental {
+            name: "Voice conversations",
+            menu_description: "Talk with Codex using /voice.",
+            announcement: "NEW: Voice conversations can now be enabled from /experimental. Restart Codex after enabling, then use /voice.",
+        },
         default_enabled: false,
     },
     FeatureSpec {

codex-rs/tui/src/bottom_pane/experimental_features_view.rs

@@ -1,5 +1,6 @@
 //! Experimental controls with popup-owned discovery and configured enablement.
 //! Failed saves retain intent for explicit retry; cancellation remains available.
+//! Server voice discovery is gated by the client package's native runtime.
 
 use crate::experimental_features::FeatureWriteResult;
 use codex_app_server_protocol::ExperimentalFeature;
@@ -53,6 +54,7 @@ pub(crate) struct ExperimentalFeatureItem {
 
 pub(crate) struct ExperimentalFeaturesView {
     features: Vec<ExperimentalFeatureItem>,
+    voice_supported: bool,
     initial_enabled: Vec<bool>,
     unconfirmed: Vec<String>,
     catalog_rx: Option<oneshot::Receiver<Result<Vec<ExperimentalFeature>, String>>>,
@@ -82,6 +84,7 @@ impl ExperimentalFeaturesView {
             }
             .to_string(),
             thread_id,
+            voice_supported: codex_realtime_webrtc::RealtimeWebrtcSession::is_supported(),
             write_rx: None,
             catalog_rx,
             unconfirmed: Vec::new(),
@@ -312,7 +315,10 @@ impl BottomPaneView for ExperimentalFeaturesView {
             Ok(features) => {
                 let mut count = 0;
                 for feature in features {
-                    if feature.stage != ExperimentalFeatureStage::Beta {
+                    if feature.stage != ExperimentalFeatureStage::Beta
+                        || (feature.name == Feature::RealtimeConversation.key()
+                            && !self.voice_supported)
+                    {
                         continue;
                     }
                     self.initial_enabled.push(feature.enabled);

codex-rs/tui/src/bottom_pane/experimental_features_view_tests.rs

@@ -207,3 +207,32 @@ fn snapshot_view(name: &str, view: &ExperimentalFeaturesView) {
     view.render(area, &mut buffer);
     insta::assert_snapshot!(name, buffer_text(&buffer));
 }
+
+#[test]
+fn voice_discovery_requires_the_client_runtime() {
+    for supported in [false, true] {
+        let (app_tx, _app_rx) = tokio::sync::mpsc::unbounded_channel();
+        let (catalog_tx, catalog_rx) = oneshot::channel();
+        let mut view = ExperimentalFeaturesView::new(
+            Vec::new(),
+            ThreadId::new(),
+            Some(catalog_rx),
+            AppEventSender::new(app_tx),
+            crate::keymap::RuntimeKeymap::defaults().list,
+        );
+        view.voice_supported = supported;
+        catalog_tx
+            .send(Ok(vec![server_feature("realtime_conversation")]))
+            .unwrap();
+        assert!(view.pre_draw_tick(Instant::now()));
+        assert_eq!(view.features.len(), usize::from(supported));
+        snapshot_view(
+            if supported {
+                "voice_runtime_available"
+            } else {
+                "voice_runtime_unavailable"
+            },
+            &view,
+        );
+    }
+}

codex-rs/tui/src/bottom_pane/snapshots/codex_tui__bottom_pane__experimental_features_view__tests__voice_runtime_available.snap

@@ -0,0 +1,13 @@
+---
+source: tui/src/bottom_pane/experimental_features_view_tests.rs
+assertion_line: 208
+expression: buffer_text(&buffer)
+---
+
+  Experimental features
+  Checked features are configured on. Some experimental features take effect
+  only in new tasks or after restarting the Codex server.
+
+› [x] Server realtime_conversation  Description supplied by the server.
+
+  Press space to select or enter to save

codex-rs/tui/src/bottom_pane/snapshots/codex_tui__bottom_pane__experimental_features_view__tests__voice_runtime_unavailable.snap

@@ -0,0 +1,14 @@
+---
+source: tui/src/bottom_pane/experimental_features_view_tests.rs
+assertion_line: 208
+expression: buffer_text(&buffer)
+---
+
+  Experimental features
+  Checked features are configured on. Some experimental features take effect
+  only in new tasks or after restarting the Codex server.
+  No server experiments available.
+
+  No experimental features available for now
+
+  Press space to select or enter to save

codex-rs/tui/src/chatwidget/snapshots/codex_tui__chatwidget__tests__experimental_features_popup.snap

@@ -1,16 +1,18 @@
 ---
 source: tui/src/chatwidget/tests/popups_and_settings.rs
+assertion_line: 3083
 expression: popup
 ---
   Experimental features
   Checked features are configured on. Some experimental features take effect
   only in new tasks or after restarting the Codex server.
 
-› [ ] JavaScript REPL  Enable a persistent Node-backed JavaScript REPL for
-                       interactive website debugging and other inline
-                       JavaScript execution capabilities.
-  [x] Shell tool       Allow the model to run shell commands.
-  [ ] Worktrees        Create isolated Git worktrees and group sessions by
-                       repository.
+› [ ] JavaScript REPL      Enable a persistent Node-backed JavaScript REPL for
+                           interactive website debugging and other inline
+                           JavaScript execution capabilities.
+  [x] Shell tool           Allow the model to run shell commands.
+  [ ] Worktrees            Create isolated Git worktrees and group sessions by
+                           repository.
+  [ ] Voice conversations  Talk with Codex using /voice.
 
   Press space to select or enter to save

codex-rs/tui/src/chatwidget/tests/popups_and_settings.rs

@@ -3039,6 +3039,7 @@ async fn experimental_features_popup_snapshot() {
     let (mut chat, _rx, _op_rx) = make_chatwidget_manual(/*model_override*/ None).await;
 
     let worktrees = Feature::Worktrees.stage();
+    let voice = Feature::RealtimeConversation.stage();
     let features = vec![
         ExperimentalFeatureItem {
             key: Feature::JsRepl.key().to_string(),
@@ -3061,6 +3062,13 @@ async fn experimental_features_popup_snapshot() {
             description: worktrees.experimental_menu_description().unwrap().to_string(),
             enabled: false,
         },
+        ExperimentalFeatureItem {
+            key: Feature::RealtimeConversation.key().to_string(),
+            writable: true,
+            name: voice.experimental_menu_name().unwrap().to_string(),
+            description: voice.experimental_menu_description().unwrap().to_string(),
+            enabled: false,
+        },
     ];
     let view = ExperimentalFeaturesView::new(
         features,

codex-rs/tui/src/snapshots/codex_tui__tooltips__tests__experimental_voice_tooltip.snap

@@ -0,0 +1,6 @@
+---
+source: tui/src/tooltips.rs
+assertion_line: 382
+expression: "available.into_iter().filter(|tip| *tip ==\nvoice_tip).collect::<Vec<_>>().join(\"\\n\")"
+---
+NEW: Voice conversations can now be enabled from /experimental. Restart Codex after enabling, then use /voice.

codex-rs/tui/src/tooltips.rs

@@ -1,4 +1,5 @@
 use codex_features::FEATURES;
+use codex_features::Feature;
 use codex_protocol::account::PlanType;
 use lazy_static::lazy_static;
 use rand::Rng;
@@ -36,14 +37,17 @@ lazy_static! {
     static ref ALL_TOOLTIPS: Vec<&'static str> = {
         let mut tips = Vec::new();
         tips.extend(TOOLTIPS.iter().copied());
-        tips.extend(experimental_tooltips());
+        tips.extend(experimental_tooltips(
+            codex_realtime_webrtc::RealtimeWebrtcSession::is_supported,
+        ));
         tips
     };
 }
 
-fn experimental_tooltips() -> Vec<&'static str> {
+fn experimental_tooltips(voice_supported: impl Fn() -> bool) -> Vec<&'static str> {
     FEATURES
         .iter()
+        .filter(|spec| spec.id != Feature::RealtimeConversation || voice_supported())
         .filter_map(|spec| spec.stage.experimental_announcement())
         .collect()
 }
@@ -358,6 +362,33 @@ mod tests {
     use rand::SeedableRng;
     use rand::rngs::StdRng;
 
+    #[test]
+    fn experimental_voice_tooltip_requires_runtime_support() {
+        let unavailable = experimental_tooltips(|| false);
+        let available = experimental_tooltips(|| true);
+        let voice_tip = FEATURES
+            .iter()
+            .find(|spec| spec.id == Feature::RealtimeConversation)
+            .and_then(|spec| spec.stage.experimental_announcement())
+            .expect("voice has an experimental announcement");
+        assert_eq!(
+            unavailable,
+            available
+                .iter()
+                .copied()
+                .filter(|tip| *tip != voice_tip)
+                .collect::<Vec<_>>()
+        );
+        insta::assert_snapshot!(
+            "experimental_voice_tooltip",
+            available
+                .into_iter()
+                .filter(|tip| *tip == voice_tip)
+                .collect::<Vec<_>>()
+                .join("\n")
+        );
+    }
+
     #[test]
     fn random_tooltip_returns_some_tip_when_available() {
         let mut rng = StdRng::seed_from_u64(42);