diff --git a/codex-rs/tui/src/bottom_pane/chat_composer.rs b/codex-rs/tui/src/bottom_pane/chat_composer.rs
index 60e6aae813..5f6a189ffe 100644
--- a/codex-rs/tui/src/bottom_pane/chat_composer.rs
+++ b/codex-rs/tui/src/bottom_pane/chat_composer.rs
@@ -256,6 +256,16 @@ impl ChatComposer<'_> {
                         self.textarea.select_all();
                         self.textarea.cut();
                         let _ = self.textarea.insert_str(format!("/{} ", cmd.command()));
+                    } else {
+                        // Special case: if the command is `/model` and the line is exactly "/model"
+                        // (no trailing space), add a space to trigger the model dropdown.
+                        if *cmd == SlashCommand::Model {
+                            let trimmed = first_line.trim_start();
+                            let expected = format!("/{}", cmd.command());
+                            if trimmed == expected {
+                                let _ = self.textarea.insert_str(" ");
+                            }
+                        }
                     }
                 }
                 (InputResult::None, true)
@@ -392,6 +402,39 @@ impl ChatComposer<'_> {
                     self.active_popup = ActivePopup::None;
                     return (InputResult::None, true);
                 }
+                // No selection in the list: treat the typed argument as the model name.
+                // Extract arguments after `/model` from the first line.
+                let first_line = self
+                    .textarea
+                    .lines()
+                    .first()
+                    .map(|s| s.as_str())
+                    .unwrap_or("");
+
+                let args = if let Some(stripped) = first_line.strip_prefix('/') {
+                    let token = stripped.trim_start();
+                    let cmd_token = token.split_whitespace().next().unwrap_or("");
+                    if cmd_token == SlashCommand::Model.command() {
+                        let rest = &token[cmd_token.len()..];
+                        rest.trim_start().to_string()
+                    } else {
+                        String::new()
+                    }
+                } else {
+                    String::new()
+                };
+
+                if !args.trim().is_empty() {
+                    // Dispatch as a command with args so normalization is applied centrally.
+                    self.app_event_tx
+                        .send(AppEvent::DispatchCommandWithArgs(SlashCommand::Model, args));
+                    // Clear composer input and close the popup.
+                    self.textarea.select_all();
+                    self.textarea.cut();
+                    self.pending_pastes.clear();
+                    self.active_popup = ActivePopup::None;
+                    return (InputResult::None, true);
+                }
                 (InputResult::None, false)
             }
             input => self.handle_input_basic(input),
diff --git a/codex-rs/tui/src/bottom_pane/model_selection_popup.rs b/codex-rs/tui/src/bottom_pane/model_selection_popup.rs
index 980c337e5f..27aec5abc3 100644
--- a/codex-rs/tui/src/bottom_pane/model_selection_popup.rs
+++ b/codex-rs/tui/src/bottom_pane/model_selection_popup.rs
@@ -70,7 +70,10 @@ impl ModelSelectionPopup {
     /// Move selection cursor down.
     pub(crate) fn move_down(&mut self) {
         let len = self.visible_rows().len();
-        if len == 0 { self.selected_idx = None; return; }
+        if len == 0 {
+            self.selected_idx = None;
+            return;
+        }
         match self.selected_idx {
             Some(idx) if idx + 1 < len => self.selected_idx = Some(idx + 1),
             None => self.selected_idx = Some(0),
@@ -81,9 +84,8 @@ impl ModelSelectionPopup {
     /// Currently selected model name, if any.
     pub(crate) fn selected_model(&self) -> Option<String> {
         let rows = self.visible_rows();
-        self.selected_idx.and_then(|idx| match rows.get(idx) {
-            Some(DisplayRow::Model { name, .. }) => Some(name.clone()),
-            None => None,
+        self.selected_idx.and_then(|idx| {
+            rows.get(idx).map(|DisplayRow::Model { name, .. }| name.clone())
         })
     }