feat: add optional pane border labels

10 files changed, 276 insertions, 13 deletions

diff --git a/src/app/api.rs b/src/app/api.rs
index c675aa6f..46429ffe 100644
--- a/src/app/api.rs
+++ b/src/app/api.rs
@@ -927,6 +927,48 @@ impl App {
                     result: ResponseResult::PaneInfo { pane },
                 }
             }
+            Method::PaneRename(params) => {
+                let Some((ws_idx, pane_id)) = self.parse_pane_id(&params.pane_id) else {
+                    return serde_json::to_string(&ErrorResponse {
+                        id: request.id,
+                        error: ErrorBody {
+                            code: "pane_not_found".into(),
+                            message: format!("pane {} not found", params.pane_id),
+                        },
+                    })
+                    .unwrap();
+                };
+                let Some(ws) = self.state.workspaces.get_mut(ws_idx) else {
+                    return serde_json::to_string(&ErrorResponse {
+                        id: request.id,
+                        error: ErrorBody {
+                            code: "pane_not_found".into(),
+                            message: format!("pane {} not found", params.pane_id),
+                        },
+                    })
+                    .unwrap();
+                };
+                let Some(pane_state) = ws.pane_state_mut(pane_id) else {
+                    return serde_json::to_string(&ErrorResponse {
+                        id: request.id,
+                        error: ErrorBody {
+                            code: "pane_not_found".into(),
+                            message: format!("pane {} not found", params.pane_id),
+                        },
+                    })
+                    .unwrap();
+                };
+                match params.label.map(|label| label.trim().to_string()) {
+                    Some(label) if !label.is_empty() => pane_state.set_manual_label(label),
+                    _ => pane_state.clear_manual_label(),
+                }
+                self.state.mark_session_dirty();
+                let pane = self.pane_info(ws_idx, pane_id).unwrap();
+                SuccessResponse {
+                    id: request.id,
+                    result: ResponseResult::PaneInfo { pane },
+                }
+            }
             Method::PaneRead(params) => {
                 let Some((ws_idx, pane_id)) = self.parse_pane_id(&params.pane_id) else {
                     return serde_json::to_string(&ErrorResponse {
diff --git a/src/app/config_io.rs b/src/app/config_io.rs
index a9199561..0bf04831 100644
--- a/src/app/config_io.rs
+++ b/src/app/config_io.rs
@@ -72,6 +72,19 @@ impl App {
         }
     }
 
+    pub(super) fn save_agent_border_labels(&mut self, enabled: bool) {
+        if self.update_config_file("agent border labels", |content| {
+            crate::config::upsert_section_bool(
+                content,
+                "ui",
+                "show_agent_labels_on_pane_borders",
+                enabled,
+            )
+        }) {
+            self.apply_config_from_disk(false);
+        }
+    }
+
     pub(super) fn save_agent_panel_scope(&mut self, scope: crate::app::state::AgentPanelScope) {
         let value = match scope {
             crate::app::state::AgentPanelScope::CurrentWorkspace => {
diff --git a/src/app/creation.rs b/src/app/creation.rs
index 4e38084c..51dac1e8 100644
--- a/src/app/creation.rs
+++ b/src/app/creation.rs
@@ -245,6 +245,7 @@ impl App {
             cwd: runtime
                 .and_then(|rt| rt.cwd())
                 .map(|cwd| cwd.display().to_string()),
+            label: pane.manual_label.clone(),
             agent: pane.effective_agent_label().map(str::to_string),
             agent_status: pane_agent_status(pane.state, pane.seen),
             revision: 0,
diff --git a/src/app/input/mod.rs b/src/app/input/mod.rs
index aa607c78..575b373d 100644
--- a/src/app/input/mod.rs
+++ b/src/app/input/mod.rs
@@ -63,7 +63,7 @@ impl App {
                     Mode::Onboarding => self.handle_onboarding_key(key),
                     Mode::ReleaseNotes => self.handle_release_notes_key(key),
                     Mode::Navigate => unreachable!(),
-                    Mode::RenameWorkspace | Mode::RenameTab => {
+                    Mode::RenameWorkspace | Mode::RenameTab | Mode::RenamePane => {
                         handle_rename_key(&mut self.state, key)
                     }
                     Mode::Resize => handle_resize_key(&mut self.state, key),
@@ -159,6 +159,9 @@ impl App {
                 SettingsAction::SaveTheme(name) => self.save_theme(&name),
                 SettingsAction::SaveSound(enabled) => self.save_sound(enabled),
                 SettingsAction::SaveToastDelivery(delivery) => self.save_toast_delivery(delivery),
+                SettingsAction::SaveAgentBorderLabels(enabled) => {
+                    self.save_agent_border_labels(enabled)
+                }
             }
         }
         if self.state.agent_panel_scope != previous_agent_panel_scope {
diff --git a/src/app/input/modal.rs b/src/app/input/modal.rs
index a76576bf..367e7e84 100644
--- a/src/app/input/modal.rs
+++ b/src/app/input/modal.rs
@@ -164,6 +164,7 @@ pub(crate) fn handle_keybind_help_key(state: &mut AppState, key: KeyEvent) {
 
 pub(super) fn open_rename_workspace(state: &mut AppState, ws_idx: usize) {
     state.selected = ws_idx;
+    state.rename_pane_target = None;
     state.name_input = state.workspaces[ws_idx].display_name();
     state.name_input_replace_on_type = false;
     state.mode = Mode::RenameWorkspace;
@@ -172,6 +173,7 @@ pub(super) fn open_rename_workspace(state: &mut AppState, ws_idx: usize) {
 pub(super) fn open_rename_active_tab(state: &mut AppState, replace_on_type: bool) {
     state.creating_new_tab = false;
     state.requested_new_tab_name = None;
+    state.rename_pane_target = None;
     if let Some(ws) = state.active.and_then(|i| state.workspaces.get(i)) {
         if let Some(name) = ws.active_tab_display_name() {
             state.name_input = name;
@@ -181,6 +183,21 @@ pub(super) fn open_rename_active_tab(state: &mut AppState, replace_on_type: bool
     }
 }
 
+pub(super) fn open_rename_pane(state: &mut AppState, pane_id: crate::layout::PaneId) {
+    let Some(ws) = state.active.and_then(|i| state.workspaces.get(i)) else {
+        return;
+    };
+    let Some(pane) = ws.pane_state(pane_id) else {
+        return;
+    };
+    state.creating_new_tab = false;
+    state.requested_new_tab_name = None;
+    state.rename_pane_target = Some(pane_id);
+    state.name_input = pane.manual_label.clone().unwrap_or_default();
+    state.name_input_replace_on_type = pane.manual_label.is_none();
+    state.mode = Mode::RenamePane;
+}
+
 fn next_new_tab_default_name(state: &AppState) -> String {
     state
         .active
@@ -192,6 +209,7 @@ fn next_new_tab_default_name(state: &AppState) -> String {
 pub(super) fn open_new_tab_dialog(state: &mut AppState) {
     state.creating_new_tab = true;
     state.requested_new_tab_name = None;
+    state.rename_pane_target = None;
     state.name_input = next_new_tab_default_name(state);
     state.name_input_replace_on_type = true;
     state.mode = Mode::RenameTab;
@@ -295,9 +313,21 @@ pub(super) fn apply_rename_action(state: &mut AppState, action: ModalAction) {
                         }
                     }
                 }
+                Mode::RenamePane => {
+                    if let (Some(ws_idx), Some(pane_id)) = (state.active, state.rename_pane_target)
+                    {
+                        if let Some(ws) = state.workspaces.get_mut(ws_idx) {
+                            if let Some(pane) = ws.pane_state_mut(pane_id) {
+                                pane.set_manual_label(new_name);
+                                state.mark_session_dirty();
+                            }
+                        }
+                    }
+                }
                 _ => {}
             }
             state.creating_new_tab = false;
+            state.rename_pane_target = None;
             state.name_input.clear();
             state.name_input_replace_on_type = false;
             leave_modal(state);
@@ -309,6 +339,7 @@ pub(super) fn apply_rename_action(state: &mut AppState, action: ModalAction) {
         ModalAction::Cancel => {
             state.creating_new_tab = false;
             state.requested_new_tab_name = None;
+            state.rename_pane_target = None;
             state.name_input.clear();
             state.name_input_replace_on_type = false;
             leave_modal(state);
@@ -432,19 +463,33 @@ pub(super) fn apply_context_menu_action(state: &mut AppState, menu: ContextMenuS
                 Mode::Navigate
             };
         }
-        (ContextMenuKind::Pane, Some("Split vertical")) => {
+        (ContextMenuKind::Pane { pane_id, .. }, Some("Rename pane")) => {
+            open_rename_pane(state, pane_id);
+        }
+        (ContextMenuKind::Pane { pane_id, .. }, Some("Clear pane name")) => {
+            if let Some(ws_idx) = state.active {
+                if let Some(ws) = state.workspaces.get_mut(ws_idx) {
+                    if let Some(pane) = ws.pane_state_mut(pane_id) {
+                        pane.clear_manual_label();
+                        state.mark_session_dirty();
+                    }
+                }
+            }
+            state.mode = Mode::Terminal;
+        }
+        (ContextMenuKind::Pane { .. }, Some("Split vertical")) => {
             state.split_pane(Direction::Horizontal);
             state.mode = Mode::Terminal;
         }
-        (ContextMenuKind::Pane, Some("Split horizontal")) => {
+        (ContextMenuKind::Pane { .. }, Some("Split horizontal")) => {
             state.split_pane(Direction::Vertical);
             state.mode = Mode::Terminal;
         }
-        (ContextMenuKind::Pane, Some("Fullscreen")) => {
+        (ContextMenuKind::Pane { .. }, Some("Fullscreen")) => {
             state.toggle_fullscreen();
             state.mode = Mode::Terminal;
         }
-        (ContextMenuKind::Pane, Some("Close pane")) => {
+        (ContextMenuKind::Pane { .. }, Some("Close pane")) => {
             state.close_pane();
             state.mode = if state.active.is_some() {
                 Mode::Terminal
diff --git a/src/app/input/mouse.rs b/src/app/input/mouse.rs
index 4a074a2e..f7997807 100644
--- a/src/app/input/mouse.rs
+++ b/src/app/input/mouse.rs
@@ -137,7 +137,10 @@ impl AppState {
                     return None;
                 }
 
-                if matches!(self.mode, Mode::RenameWorkspace | Mode::RenameTab) {
+                if matches!(
+                    self.mode,
+                    Mode::RenameWorkspace | Mode::RenameTab | Mode::RenamePane
+                ) {
                     let action = self
                         .rename_modal_inner()
                         .map(crate::ui::rename_button_rects)
@@ -678,8 +681,17 @@ impl AppState {
             MouseEventKind::Down(MouseButton::Right) if !in_sidebar => {
                 if let Some(info) = self.pane_mouse_target(mouse.column, mouse.row).cloned() {
                     self.focus_pane(info.id);
+                    let has_manual_label = self
+                        .active
+                        .and_then(|ws_idx| self.workspaces.get(ws_idx))
+                        .and_then(|ws| ws.pane_state(info.id))
+                        .and_then(|pane| pane.manual_label.as_ref())
+                        .is_some();
                     self.context_menu = Some(ContextMenuState {
-                        kind: ContextMenuKind::Pane,
+                        kind: ContextMenuKind::Pane {
+                            pane_id: info.id,
+                            has_manual_label,
+                        },
                         x: mouse.column,
                         y: mouse.row,
                         list: MenuListState::new(0),
diff --git a/src/app/input/navigate.rs b/src/app/input/navigate.rs
index 3bc8da78..bb88c46b 100644
--- a/src/app/input/navigate.rs
+++ b/src/app/input/navigate.rs
@@ -368,6 +368,7 @@ pub(crate) enum NavigateAction {
     PreviousTab,
     NextTab,
     CloseTab,
+    RenamePane,
     FocusPaneLeft,
     FocusPaneDown,
     FocusPaneUp,
@@ -432,6 +433,12 @@ fn navigate_action_for_key(state: &AppState, key: &KeyEvent) -> Option<NavigateA
     {
         return Some(NavigateAction::CloseTab);
     }
+    if kb
+        .rename_pane
+        .is_some_and(|(code, mods)| key_matches(key, code, mods))
+    {
+        return Some(NavigateAction::RenamePane);
+    }
     if key_matches(key, kb.split_vertical.0, kb.split_vertical.1) {
         return Some(NavigateAction::SplitVertical);
     }
@@ -508,6 +515,15 @@ pub(super) fn execute_navigate_action(state: &mut AppState, action: NavigateActi
             state.close_tab();
             leave_navigate_mode(state);
         }
+        NavigateAction::RenamePane => {
+            if let Some(pane_id) = state
+                .active
+                .and_then(|ws_idx| state.workspaces.get(ws_idx))
+                .and_then(|ws| ws.focused_pane_id())
+            {
+                super::modal::open_rename_pane(state, pane_id);
+            }
+        }
         NavigateAction::FocusPaneLeft => state.navigate_pane(NavDirection::Left),
         NavigateAction::FocusPaneDown => state.navigate_pane(NavDirection::Down),
         NavigateAction::FocusPaneUp => state.navigate_pane(NavDirection::Up),
diff --git a/src/app/input/settings.rs b/src/app/input/settings.rs
index 67144a28..9e89e515 100644
--- a/src/app/input/settings.rs
+++ b/src/app/input/settings.rs
@@ -16,6 +16,7 @@ pub(super) enum SettingsAction {
     SaveTheme(String),
     SaveSound(bool),
     SaveToastDelivery(ToastDelivery),
+    SaveAgentBorderLabels(bool),
 }
 
 impl App {
@@ -25,6 +26,9 @@ impl App {
                 SettingsAction::SaveTheme(name) => self.save_theme(&name),
                 SettingsAction::SaveSound(enabled) => self.save_sound(enabled),
                 SettingsAction::SaveToastDelivery(delivery) => self.save_toast_delivery(delivery),
+                SettingsAction::SaveAgentBorderLabels(enabled) => {
+                    self.save_agent_border_labels(enabled)
+                }
             }
         }
     }
@@ -157,6 +161,30 @@ pub(super) fn update_settings_state(state: &mut AppState, key: KeyEvent) -> Opti
                 state.settings.list.selected = usize::from(!state.sound_enabled());
             }
             KeyCode::Tab | KeyCode::Right | KeyCode::Char('l') => {
+                state.settings.section = SettingsSection::PaneLabels;
+                state.settings.list.selected = usize::from(!state.agent_border_labels_enabled());
+            }
+            _ => {
+                if let Some(super::modal::ModalAction::Close) =
+                    super::modal::modal_action_from_key(&key, super::modal::SETTINGS_ACTIONS)
+                {
+                    cancel_settings(state);
+                }
+            }
+        },
+        SettingsSection::PaneLabels => match key.code {
+            KeyCode::Up | KeyCode::Char('k') | KeyCode::Down | KeyCode::Char('j') => {
+                state.settings.list.selected = 1 - state.settings.list.selected.min(1);
+            }
+            KeyCode::Enter | KeyCode::Char(' ') => {
+                let enabled = state.settings.list.selected == 0;
+                return Some(SettingsAction::SaveAgentBorderLabels(enabled));
+            }
+            KeyCode::BackTab | KeyCode::Left | KeyCode::Char('h') => {
+                state.settings.section = SettingsSection::Toast;
+                state.settings.list.selected = toast_delivery_index(state.toast_delivery());
+            }
+            KeyCode::Tab | KeyCode::Right | KeyCode::Char('l') => {
                 state.settings.section = SettingsSection::Theme;
                 state.settings.list.selected = current_theme_index(&state.theme_name);
             }
@@ -252,6 +280,14 @@ impl AppState {
                     None
                 }
             }
+            SettingsSection::PaneLabels => {
+                let list_y = area.y + 3;
+                if row >= list_y && row < list_y + 2 {
+                    Some((row - list_y) as usize)
+                } else {
+                    None
+                }
+            }
         }
     }
 
@@ -264,6 +300,9 @@ impl AppState {
                         SettingsSection::Theme => current_theme_index(&self.theme_name),
                         SettingsSection::Sound => usize::from(!self.sound_enabled()),
                         SettingsSection::Toast => toast_delivery_index(self.toast_delivery()),
+                        SettingsSection::PaneLabels => {
+                            usize::from(!self.agent_border_labels_enabled())
+                        }
                     });
                     return None;
                 }
@@ -282,6 +321,10 @@ impl AppState {
                             let delivery = toast_delivery_for_index(idx);
                             Some(SettingsAction::SaveToastDelivery(delivery))
                         }
+                        SettingsSection::PaneLabels => {
+                            let enabled = idx == 0;
+                            Some(SettingsAction::SaveAgentBorderLabels(enabled))
+                        }
                     };
                 }
 
diff --git a/src/app/mod.rs b/src/app/mod.rs
index 60e38f5b..43d15bec 100644
--- a/src/app/mod.rs
+++ b/src/app/mod.rs
@@ -292,6 +292,7 @@ impl App {
             request_clipboard_write: None,
             creating_new_tab: false,
             requested_new_tab_name: None,
+            rename_pane_target: None,
             request_complete_onboarding: false,
             name_input: String::new(),
             name_input_replace_on_type: false,
@@ -344,6 +345,7 @@ impl App {
             sidebar_section_split,
             agent_panel_scope,
             confirm_close: config.ui.confirm_close,
+            show_agent_labels_on_pane_borders: config.ui.show_agent_labels_on_pane_borders,
             pane_scrollback_limit_bytes: config.advanced.scrollback_limit_bytes,
             accent: crate::config::parse_color(&config.ui.accent),
             sound: config.ui.sound.clone(),
@@ -649,6 +651,8 @@ impl App {
                 self.state.sidebar_width = config.ui.sidebar_width;
             }
             self.state.confirm_close = config.ui.confirm_close;
+            self.state.show_agent_labels_on_pane_borders =
+                config.ui.show_agent_labels_on_pane_borders;
             self.state.agent_panel_scope =
                 agent_panel_scope_from_config(config.ui.agent_panel_scope);
             self.state.agent_panel_scroll = 0;
@@ -809,7 +813,7 @@ impl App {
             Mode::Navigate => {
                 self.handle_navigate_key(key);
             }
-            Mode::RenameWorkspace | Mode::RenameTab => {
+            Mode::RenameWorkspace | Mode::RenameTab | Mode::RenamePane => {
                 input::handle_rename_key(&mut self.state, key_event);
             }
             Mode::Resize => {
@@ -1482,6 +1486,54 @@ mod tests {
         assert!(app.state.should_quit);
     }
 
+    #[test]
+    fn pane_rename_request_sets_and_clears_manual_label() {
+        let mut app = test_app();
+        let workspace = Workspace::test_new("api-pane-rename");
+        let pane = workspace.tabs[0].root_pane;
+        app.state.workspaces = vec![workspace];
+        app.state.active = Some(0);
+        app.state.selected = 0;
+
+        let pane_id = app.pane_info(0, pane).unwrap().pane_id;
+        let response = app.handle_api_request(crate::api::schema::Request {
+            id: "req_pane_rename".into(),
+            method: crate::api::schema::Method::PaneRename(crate::api::schema::PaneRenameParams {
+                pane_id: pane_id.clone(),
+                label: Some("reviewer".into()),
+            }),
+        });
+        let response: serde_json::Value = serde_json::from_str(&response).unwrap();
+
+        assert_eq!(response["result"]["type"], "pane_info");
+        assert_eq!(response["result"]["pane"]["label"], "reviewer");
+        assert_eq!(
+            app.state.workspaces[0]
+                .pane_state(pane)
+                .unwrap()
+                .manual_label
+                .as_deref(),
+            Some("reviewer")
+        );
+
+        let response = app.handle_api_request(crate::api::schema::Request {
+            id: "req_pane_rename_clear".into(),
+            method: crate::api::schema::Method::PaneRename(crate::api::schema::PaneRenameParams {
+                pane_id,
+                label: None,
+            }),
+        });
+        let response: serde_json::Value = serde_json::from_str(&response).unwrap();
+
+        assert_eq!(response["result"]["type"], "pane_info");
+        assert!(response["result"]["pane"].get("label").is_none());
+        assert!(app.state.workspaces[0]
+            .pane_state(pane)
+            .unwrap()
+            .manual_label
+            .is_none());
+    }
+
     #[tokio::test]
     async fn pane_split_request_targets_pane_in_background_tab() {
         let _guard = config_env_lock().lock().unwrap();
diff --git a/src/app/state.rs b/src/app/state.rs
index 134d86bd..dd081298 100644
--- a/src/app/state.rs
+++ b/src/app/state.rs
@@ -383,6 +383,7 @@ pub enum Mode {
     Terminal,
     RenameWorkspace,
     RenameTab,
+    RenamePane,
     Resize,
     ConfirmClose,
     ContextMenu,
@@ -408,16 +409,18 @@ pub enum SettingsSection {
     Theme,
     Sound,
     Toast,
+    PaneLabels,
 }
 
 impl SettingsSection {
-    pub const ALL: &[Self] = &[Self::Theme, Self::Sound, Self::Toast];
+    pub const ALL: &[Self] = &[Self::Theme, Self::Sound, Self::Toast, Self::PaneLabels];
 
     pub fn label(self) -> &'static str {
         match self {
             Self::Theme => "theme",
             Self::Sound => "sound",
             Self::Toast => "toasts",
+            Self::PaneLabels => "pane labels",
         }
     }
 }
@@ -554,9 +557,17 @@ pub(crate) struct TabPressState {
 
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
 pub enum ContextMenuKind {
-    Workspace { ws_idx: usize },
-    Tab { ws_idx: usize, tab_idx: usize },
-    Pane,
+    Workspace {
+        ws_idx: usize,
+    },
+    Tab {
+        ws_idx: usize,
+        tab_idx: usize,
+    },
+    Pane {
+        pane_id: PaneId,
+        has_manual_label: bool,
+    },
 }
 
 /// Right-click context menu state.
@@ -572,7 +583,22 @@ impl ContextMenuState {
         match self.kind {
             ContextMenuKind::Workspace { .. } => &["Rename", "Close"],
             ContextMenuKind::Tab { .. } => &["New tab", "Rename", "Close"],
-            ContextMenuKind::Pane => &[
+            ContextMenuKind::Pane {
+                has_manual_label: true,
+                ..
+            } => &[
+                "Rename pane",
+                "Clear pane name",
+                "Split vertical",
+                "Split horizontal",
+                "Fullscreen",
+                "Close pane",
+            ],
+            ContextMenuKind::Pane {
+                has_manual_label: false,
+                ..
+            } => &[
+                "Rename pane",
                 "Split vertical",
                 "Split horizontal",
                 "Fullscreen",
@@ -645,6 +671,7 @@ pub struct AppState {
     pub request_clipboard_write: Option<Vec<u8>>,
     pub creating_new_tab: bool,
     pub requested_new_tab_name: Option<String>,
+    pub rename_pane_target: Option<PaneId>,
     pub request_complete_onboarding: bool,
     pub name_input: String,
     pub name_input_replace_on_type: bool,
@@ -683,6 +710,7 @@ pub struct AppState {
     pub sidebar_section_split: f32,
     pub agent_panel_scope: AgentPanelScope,
     pub confirm_close: bool,
+    pub show_agent_labels_on_pane_borders: bool,
     pub pane_scrollback_limit_bytes: usize,
     #[allow(dead_code)] // kept for backward compat; palette.accent is the source of truth
     pub accent: Color,
@@ -719,6 +747,10 @@ impl AppState {
         self.toast_config.delivery
     }
 
+    pub fn agent_border_labels_enabled(&self) -> bool {
+        self.show_agent_labels_on_pane_borders
+    }
+
     pub fn is_prefix(&self, key: &crossterm::event::KeyEvent) -> bool {
         key_matches(key, self.prefix_code, self.prefix_mods)
     }
@@ -797,6 +829,7 @@ impl AppState {
             request_clipboard_write: None,
             creating_new_tab: false,
             requested_new_tab_name: None,
+            rename_pane_target: None,
             request_complete_onboarding: false,
             name_input: String::new(),
             name_input_replace_on_type: false,
@@ -844,6 +877,7 @@ impl AppState {
             sidebar_section_split: 0.5,
             agent_panel_scope: AgentPanelScope::AllWorkspaces,
             confirm_close: true,
+            show_agent_labels_on_pane_borders: false,
             pane_scrollback_limit_bytes: crate::config::DEFAULT_SCROLLBACK_LIMIT_BYTES,
             accent: Color::Cyan,
             sound: SoundConfig {
@@ -877,6 +911,8 @@ impl AppState {
                 next_tab_label: None,
                 close_tab: None,
                 close_tab_label: None,
+                rename_pane: None,
+                rename_pane_label: None,
                 focus_pane_left: None,
                 focus_pane_left_label: None,
                 focus_pane_down: None,