refactor: extract panel registry and pane context from workspace screen

Replace hardcoded renderContent() switch and per-kind descriptor logic
with a registry-based panel interface. Each panel type (agent, draft,
terminal, file) now self-registers with its component, useDescriptor
hook, and optional confirmClose. Panels access workspace context via
usePaneContext() instead of prop drilling. This prepares the workspace
screen for split pane support.

packages/app/src/panels/agent-panel.tsx

@@ -0,0 +1,85 @@
+import { Bot } from "lucide-react-native";
+import invariant from "tiny-invariant";
+import { AgentReadyScreen } from "@/screens/agent/agent-ready-screen";
+import { ClaudeIcon } from "@/components/icons/claude-icon";
+import { CodexIcon } from "@/components/icons/codex-icon";
+import { usePaneContext } from "@/panels/pane-context";
+import type { PanelDescriptor, PanelRegistration } from "@/panels/panel-registry";
+import { useSessionStore, type Agent } from "@/stores/session-store";
+import { deriveSidebarStateBucket } from "@/utils/sidebar-agent-state";
+
+function formatProviderLabel(provider: Agent["provider"]): string {
+  if (provider === "claude") {
+    return "Claude";
+  }
+  if (provider === "codex") {
+    return "Codex";
+  }
+  if (!provider) {
+    return "Agent";
+  }
+  return provider.charAt(0).toUpperCase() + provider.slice(1);
+}
+
+function resolveWorkspaceAgentTabLabel(title: string | null | undefined): string | null {
+  if (typeof title !== "string") {
+    return null;
+  }
+  const normalized = title.trim();
+  if (!normalized) {
+    return null;
+  }
+  if (normalized.toLowerCase() === "new agent") {
+    return null;
+  }
+  return normalized;
+}
+
+function useAgentPanelDescriptor(
+  target: { kind: "agent"; agentId: string },
+  context: { serverId: string }
+): PanelDescriptor {
+  const agent = useSessionStore(
+    (state) => state.sessions[context.serverId]?.agents?.get(target.agentId) ?? null
+  );
+  const provider = agent?.provider ?? "codex";
+  const label = resolveWorkspaceAgentTabLabel(agent?.title);
+  const icon = provider === "claude" ? ClaudeIcon : provider === "codex" ? CodexIcon : Bot;
+
+  return {
+    label: label ?? "",
+    subtitle: `${formatProviderLabel(provider)} agent`,
+    titleState: label ? "ready" : "loading",
+    icon,
+    statusBucket: agent
+      ? deriveSidebarStateBucket({
+          status: agent.status,
+          pendingPermissionCount: agent.pendingPermissions.length,
+          requiresAttention: agent.requiresAttention,
+          attentionReason: agent.attentionReason,
+        })
+      : null,
+  };
+}
+
+function AgentPanel() {
+  const { serverId, target, openFileInWorkspace } = usePaneContext();
+  invariant(target.kind === "agent", "AgentPanel requires agent target");
+  return (
+    <AgentReadyScreen
+      serverId={serverId}
+      agentId={target.agentId}
+      showExplorerSidebar={false}
+      wrapWithExplorerSidebarProvider={false}
+      onOpenWorkspaceFile={({ filePath }) => {
+        openFileInWorkspace(filePath);
+      }}
+    />
+  );
+}
+
+export const agentPanelRegistration: PanelRegistration<"agent"> = {
+  kind: "agent",
+  component: AgentPanel,
+  useDescriptor: useAgentPanelDescriptor,
+};

packages/app/src/panels/draft-panel.tsx

@@ -0,0 +1,56 @@
+import { Pencil } from "lucide-react-native";
+import invariant from "tiny-invariant";
+import { WorkspaceDraftAgentTab } from "@/screens/workspace/workspace-draft-agent-tab";
+import { usePaneContext } from "@/panels/pane-context";
+import type { PanelRegistration } from "@/panels/panel-registry";
+import { useSessionStore } from "@/stores/session-store";
+import { normalizeAgentSnapshot } from "@/utils/agent-snapshots";
+
+function useDraftPanelDescriptor() {
+  return {
+    label: "New Agent",
+    subtitle: "New Agent",
+    titleState: "ready" as const,
+    icon: Pencil,
+    statusBucket: null,
+  };
+}
+
+function DraftPanel() {
+  const {
+    serverId,
+    workspaceId,
+    tabId,
+    target,
+    openFileInWorkspace,
+    retargetCurrentTab,
+  } = usePaneContext();
+  invariant(target.kind === "draft", "DraftPanel requires draft target");
+
+  return (
+    <WorkspaceDraftAgentTab
+      serverId={serverId}
+      workspaceId={workspaceId}
+      tabId={tabId}
+      draftId={target.draftId}
+      onOpenWorkspaceFile={({ filePath }) => {
+        openFileInWorkspace(filePath);
+      }}
+      onCreated={(agentSnapshot) => {
+        const normalized = normalizeAgentSnapshot(agentSnapshot, serverId);
+        retargetCurrentTab({ kind: "agent", agentId: agentSnapshot.id });
+        useSessionStore.getState().setAgents(serverId, (prev) => {
+          const next = new Map(prev);
+          next.set(agentSnapshot.id, normalized);
+          return next;
+        });
+      }}
+    />
+  );
+}
+
+export const draftPanelRegistration: PanelRegistration<"draft"> = {
+  kind: "draft",
+  component: DraftPanel,
+  useDescriptor: useDraftPanelDescriptor,
+};

packages/app/src/panels/file-panel.tsx

@@ -0,0 +1,34 @@
+import { FileText } from "lucide-react-native";
+import invariant from "tiny-invariant";
+import { FilePane } from "@/components/file-pane";
+import { usePaneContext } from "@/panels/pane-context";
+import type { PanelRegistration } from "@/panels/panel-registry";
+
+function useFilePanelDescriptor(target: { kind: "file"; path: string }) {
+  const fileName = target.path.split("/").filter(Boolean).pop() ?? target.path;
+  return {
+    label: fileName,
+    subtitle: target.path,
+    titleState: "ready" as const,
+    icon: FileText,
+    statusBucket: null,
+  };
+}
+
+function FilePanel() {
+  const { serverId, workspaceId, target } = usePaneContext();
+  invariant(target.kind === "file", "FilePanel requires file target");
+  return (
+    <FilePane
+      serverId={serverId}
+      workspaceRoot={workspaceId}
+      filePath={target.path}
+    />
+  );
+}
+
+export const filePanelRegistration: PanelRegistration<"file"> = {
+  kind: "file",
+  component: FilePanel,
+  useDescriptor: useFilePanelDescriptor,
+};

packages/app/src/panels/pane-context.tsx

@@ -0,0 +1,32 @@
+import { createContext, useContext, type ReactNode } from "react";
+import invariant from "tiny-invariant";
+import type { WorkspaceTabTarget } from "@/stores/workspace-tabs-store";
+
+export interface PaneContextValue {
+  serverId: string;
+  workspaceId: string;
+  tabId: string;
+  target: WorkspaceTabTarget;
+  openTab(target: WorkspaceTabTarget): void;
+  closeCurrentTab(): void;
+  retargetCurrentTab(target: WorkspaceTabTarget): void;
+  openFileInWorkspace(filePath: string): void;
+}
+
+const PaneContext = createContext<PaneContextValue | null>(null);
+
+export function PaneProvider({
+  value,
+  children,
+}: {
+  value: PaneContextValue;
+  children: ReactNode;
+}) {
+  return <PaneContext.Provider value={value}>{children}</PaneContext.Provider>;
+}
+
+export function usePaneContext(): PaneContextValue {
+  const value = useContext(PaneContext);
+  invariant(value, "PaneContext is required");
+  return value;
+}

packages/app/src/panels/panel-registry.ts

@@ -0,0 +1,50 @@
+import type { ComponentType } from "react";
+import type { WorkspaceTabTarget } from "@/stores/workspace-tabs-store";
+import type { SidebarStateBucket } from "@/utils/sidebar-agent-state";
+
+export interface PanelIconProps {
+  size: number;
+  color: string;
+}
+
+export interface PanelDescriptor {
+  label: string;
+  subtitle: string;
+  titleState: "ready" | "loading";
+  icon: ComponentType<PanelIconProps>;
+  statusBucket: SidebarStateBucket | null;
+}
+
+export interface PanelDescriptorContext {
+  serverId: string;
+  workspaceId: string;
+}
+
+export interface PanelRegistration<
+  K extends WorkspaceTabTarget["kind"] = WorkspaceTabTarget["kind"],
+> {
+  kind: K;
+  component: ComponentType;
+  useDescriptor(
+    target: Extract<WorkspaceTabTarget, { kind: K }>,
+    context: PanelDescriptorContext
+  ): PanelDescriptor;
+  confirmClose?(
+    target: Extract<WorkspaceTabTarget, { kind: K }>,
+    context: PanelDescriptorContext
+  ): Promise<boolean>;
+}
+
+const panelRegistry = new Map<WorkspaceTabTarget["kind"], PanelRegistration>();
+
+export function registerPanel<K extends WorkspaceTabTarget["kind"]>(
+  registration: PanelRegistration<K>
+): void {
+  panelRegistry.set(registration.kind, registration as unknown as PanelRegistration);
+}
+
+export function getPanelRegistration(
+  kind: WorkspaceTabTarget["kind"]
+): PanelRegistration | undefined {
+  return panelRegistry.get(kind);
+}

packages/app/src/panels/register-panels.ts

@@ -0,0 +1,18 @@
+import { agentPanelRegistration } from "@/panels/agent-panel";
+import { draftPanelRegistration } from "@/panels/draft-panel";
+import { filePanelRegistration } from "@/panels/file-panel";
+import { registerPanel } from "@/panels/panel-registry";
+import { terminalPanelRegistration } from "@/panels/terminal-panel";
+
+let panelsRegistered = false;
+
+export function ensurePanelsRegistered(): void {
+  if (panelsRegistered) {
+    return;
+  }
+  registerPanel(draftPanelRegistration);
+  registerPanel(agentPanelRegistration);
+  registerPanel(terminalPanelRegistration);
+  registerPanel(filePanelRegistration);
+  panelsRegistered = true;
+}

packages/app/src/panels/terminal-panel.tsx

@@ -0,0 +1,80 @@
+import { useQuery } from "@tanstack/react-query";
+import { Terminal } from "lucide-react-native";
+import { View } from "react-native";
+import { useIsFocused } from "@react-navigation/native";
+import invariant from "tiny-invariant";
+import type { ListTerminalsResponse } from "@server/shared/messages";
+import { TerminalPane } from "@/components/terminal-pane";
+import { usePaneContext } from "@/panels/pane-context";
+import type { PanelDescriptor, PanelRegistration } from "@/panels/panel-registry";
+import { useSessionStore } from "@/stores/session-store";
+
+type ListTerminalsPayload = ListTerminalsResponse["payload"];
+
+function trimNonEmpty(value: string | null | undefined): string | null {
+  if (typeof value !== "string") {
+    return null;
+  }
+  const trimmed = value.trim();
+  return trimmed.length > 0 ? trimmed : null;
+}
+
+function useTerminalPanelDescriptor(
+  target: { kind: "terminal"; terminalId: string },
+  context: { serverId: string; workspaceId: string }
+): PanelDescriptor {
+  const client = useSessionStore((state) => state.sessions[context.serverId]?.client ?? null);
+  const terminalsQuery = useQuery({
+    queryKey: ["terminals", context.serverId, context.workspaceId] as const,
+    enabled: Boolean(client && context.workspaceId),
+    queryFn: async (): Promise<ListTerminalsPayload> => {
+      if (!client) {
+        return { cwd: context.workspaceId, terminals: [], requestId: "missing-client" };
+      }
+      return client.listTerminals(context.workspaceId);
+    },
+    staleTime: 5_000,
+  });
+  const terminal =
+    terminalsQuery.data?.terminals.find((entry) => entry.id === target.terminalId) ?? null;
+
+  return {
+    label: trimNonEmpty(terminal?.name ?? null) ?? "Terminal",
+    subtitle: "Terminal",
+    titleState: "ready",
+    icon: Terminal,
+    statusBucket: null,
+  };
+}
+
+function TerminalPanel() {
+  const isFocused = useIsFocused();
+  const { serverId, workspaceId, target, openTab } = usePaneContext();
+  invariant(target.kind === "terminal", "TerminalPanel requires terminal target");
+
+  if (!isFocused) {
+    return <View style={{ flex: 1 }} />;
+  }
+
+  return (
+    <TerminalPane
+      serverId={serverId}
+      cwd={workspaceId}
+      selectedTerminalId={target.terminalId}
+      onSelectedTerminalIdChange={(terminalId) => {
+        if (!terminalId) {
+          return;
+        }
+        openTab({ kind: "terminal", terminalId });
+      }}
+      hideHeader
+      manageTerminalDirectorySubscription={false}
+    />
+  );
+}
+
+export const terminalPanelRegistration: PanelRegistration<"terminal"> = {
+  kind: "terminal",
+  component: TerminalPanel,
+  useDescriptor: useTerminalPanelDescriptor,
+};

packages/app/src/screens/workspace/workspace-bulk-close.test.ts

@@ -10,11 +10,7 @@ function makeAgentTab(id: string): WorkspaceTabDescriptor {
     key: `agent_${id}`,
     tabId: `agent_${id}`,
     kind: "agent",
-    agentId: id,
+    target: { kind: "agent", agentId: id },
-    provider: "codex",
-    label: `Agent ${id}`,
-    subtitle: "",
-    titleState: "ready",
   };
 }
 
@@ -23,9 +19,7 @@ function makeTerminalTab(id: string): WorkspaceTabDescriptor {
     key: `terminal_${id}`,
     tabId: `terminal_${id}`,
     kind: "terminal",
-    terminalId: id,
+    target: { kind: "terminal", terminalId: id },
-    label: `Terminal ${id}`,
-    subtitle: "",
   };
 }
 
@@ -34,9 +28,7 @@ function makeFileTab(path: string): WorkspaceTabDescriptor {
     key: `file_${path}`,
     tabId: `file_${path}`,
     kind: "file",
-    filePath: path,
+    target: { kind: "file", path },
-    label: path.split("/").pop() ?? path,
-    subtitle: path,
   };
 }
 

packages/app/src/screens/workspace/workspace-bulk-close.ts

@@ -14,12 +14,12 @@ export function classifyBulkClosableTabs(tabs: WorkspaceTabDescriptor[]): BulkCl
   };
 
   for (const tab of tabs) {
-    if (tab.kind === "agent") {
+    if (tab.target.kind === "agent") {
-      groups.agentTabs.push({ tabId: tab.tabId, agentId: tab.agentId });
+      groups.agentTabs.push({ tabId: tab.tabId, agentId: tab.target.agentId });
       continue;
     }
-    if (tab.kind === "terminal") {
+    if (tab.target.kind === "terminal") {
-      groups.terminalTabs.push({ tabId: tab.tabId, terminalId: tab.terminalId });
+      groups.terminalTabs.push({ tabId: tab.tabId, terminalId: tab.target.terminalId });
       continue;
     }
     groups.otherTabs.push({ tabId: tab.tabId });

packages/app/src/screens/workspace/workspace-desktop-tabs-row.tsx

@@ -1,4 +1,4 @@
-import { useCallback, useMemo, useState, type Dispatch, type SetStateAction } from "react";
+import { useCallback, useEffect, useMemo, useState, type Dispatch, type SetStateAction } from "react";
 import { ActivityIndicator, Pressable, ScrollView, Text, View, type LayoutChangeEvent } from "react-native";
 import { Plus, X } from "lucide-react-native";
 import { StyleSheet, useUnistyles } from "react-native-unistyles";
@@ -14,13 +14,13 @@ import { Shortcut } from "@/components/ui/shortcut";
 import { Tooltip, TooltipContent, TooltipTrigger } from "@/components/ui/tooltip";
 import { useWorkspaceTabLayout } from "@/screens/workspace/use-workspace-tab-layout";
 import {
-  deriveWorkspaceTabPresentation,
+  useWorkspaceTabPresentation,
   WorkspaceTabIcon,
+  type WorkspaceTabPresentation,
 } from "@/screens/workspace/workspace-tab-presentation";
 import { buildWorkspaceTabMenuEntries } from "@/screens/workspace/workspace-tab-menu";
 import type { WorkspaceTabDescriptor } from "@/screens/workspace/workspace-tabs-types";
 import { encodeFilePathForPathSegment } from "@/utils/host-routes";
-import type { Agent } from "@/stores/session-store";
 
 const DROPDOWN_WIDTH = 220;
 const LOADING_TAB_LABEL_SKELETON_WIDTH = 80;
@@ -29,8 +29,8 @@ type NewTabOptionId = "__new_tab_agent__";
 type WorkspaceDesktopTabsRowProps = {
   tabs: WorkspaceTabDescriptor[];
   activeTabKey: string;
-  agentsById: Map<string, Agent>;
   normalizedServerId: string;
+  normalizedWorkspaceId: string;
   hoveredCloseTabKey: string | null;
   setHoveredTabKey: Dispatch<SetStateAction<string | null>>;
   setHoveredCloseTabKey: Dispatch<SetStateAction<string | null>>;
@@ -49,11 +49,242 @@ type WorkspaceDesktopTabsRowProps = {
   onReorderTabs: (nextTabs: WorkspaceTabDescriptor[]) => void;
 };
 
+function getFallbackTabLabel(tab: WorkspaceTabDescriptor): string {
+  if (tab.target.kind === "draft") {
+    return "New Agent";
+  }
+  if (tab.target.kind === "terminal") {
+    return "Terminal";
+  }
+  if (tab.target.kind === "file") {
+    return tab.target.path.split("/").filter(Boolean).pop() ?? tab.target.path;
+  }
+  return "";
+}
+
+function getCloseButtonTestId(tab: WorkspaceTabDescriptor): string {
+  if (tab.target.kind === "agent") {
+    return `workspace-agent-close-${tab.target.agentId}`;
+  }
+  if (tab.target.kind === "terminal") {
+    return `workspace-terminal-close-${tab.target.terminalId}`;
+  }
+  if (tab.target.kind === "draft") {
+    return `workspace-draft-close-${tab.target.draftId}`;
+  }
+  return `workspace-file-close-${encodeFilePathForPathSegment(tab.target.path)}`;
+}
+
+function TabChip({
+  tab,
+  index,
+  tabCount,
+  isActive,
+  resolvedTabWidth,
+  showLabel,
+  showCloseButton,
+  isCloseHovered,
+  isClosingTab,
+  normalizedServerId,
+  normalizedWorkspaceId,
+  setHoveredTabKey,
+  setHoveredCloseTabKey,
+  onNavigateTab,
+  onCloseTab,
+  onCopyResumeCommand,
+  onCopyAgentId,
+  onCloseTabsToLeft,
+  onCloseTabsToRight,
+  onCloseOtherTabs,
+  onPresentationChange,
+  dragHandleProps,
+}: {
+  tab: WorkspaceTabDescriptor;
+  index: number;
+  tabCount: number;
+  isActive: boolean;
+  resolvedTabWidth: number;
+  showLabel: boolean;
+  showCloseButton: boolean;
+  isCloseHovered: boolean;
+  isClosingTab: boolean;
+  normalizedServerId: string;
+  normalizedWorkspaceId: string;
+  setHoveredTabKey: Dispatch<SetStateAction<string | null>>;
+  setHoveredCloseTabKey: Dispatch<SetStateAction<string | null>>;
+  onNavigateTab: (tabId: string) => void;
+  onCloseTab: (tabId: string) => Promise<void> | void;
+  onCopyResumeCommand: (agentId: string) => Promise<void> | void;
+  onCopyAgentId: (agentId: string) => Promise<void> | void;
+  onCloseTabsToLeft: (tabId: string) => Promise<void> | void;
+  onCloseTabsToRight: (tabId: string) => Promise<void> | void;
+  onCloseOtherTabs: (tabId: string) => Promise<void> | void;
+  onPresentationChange: (tabKey: string, presentation: WorkspaceTabPresentation) => void;
+  dragHandleProps: any;
+}) {
+  const { theme } = useUnistyles();
+  const presentation = useWorkspaceTabPresentation({
+    tab,
+    serverId: normalizedServerId,
+    workspaceId: normalizedWorkspaceId,
+  });
+
+  useEffect(() => {
+    onPresentationChange(tab.key, presentation);
+  }, [onPresentationChange, presentation, tab.key]);
+
+  const tooltipLabel =
+    presentation.titleState === "loading" ? "Loading agent title" : presentation.label;
+  const contextMenuTestId = `workspace-tab-context-${tab.key}`;
+  const menuEntries = buildWorkspaceTabMenuEntries({
+    surface: "desktop",
+    tab,
+    index,
+    tabCount,
+    menuTestIDBase: contextMenuTestId,
+    onCopyResumeCommand,
+    onCopyAgentId,
+    onCloseTab,
+    onCloseTabsBefore: onCloseTabsToLeft,
+    onCloseTabsAfter: onCloseTabsToRight,
+    onCloseOtherTabs,
+  });
+
+  return (
+    <ContextMenu key={tab.key}>
+      <Tooltip delayDuration={400} enabledOnDesktop enabledOnMobile={false}>
+        <TooltipTrigger asChild triggerRefProp="triggerRef">
+          <ContextMenuTrigger
+            testID={`workspace-tab-${tab.key}`}
+            enabledOnMobile={false}
+            style={({ hovered, pressed }) => [
+              styles.tab,
+              {
+                minWidth: resolvedTabWidth,
+                width: resolvedTabWidth,
+                maxWidth: resolvedTabWidth,
+              },
+              isActive && styles.tabActive,
+              !isActive && (hovered || pressed || isCloseHovered) && styles.tabHovered,
+            ]}
+            onHoverIn={() => {
+              setHoveredTabKey(tab.key);
+            }}
+            onHoverOut={() => {
+              setHoveredTabKey((current) => (current === tab.key ? null : current));
+            }}
+            onPressIn={() => {
+              onNavigateTab(tab.tabId);
+            }}
+            onPress={() => {
+              onNavigateTab(tab.tabId);
+            }}
+            accessibilityLabel={tooltipLabel}
+          >
+            <View
+              {...(dragHandleProps?.attributes as any)}
+              {...(dragHandleProps?.listeners as any)}
+              ref={dragHandleProps?.setActivatorNodeRef}
+              style={styles.tabHandle}
+            >
+              <View style={styles.tabIcon}>
+                <WorkspaceTabIcon presentation={presentation} active={isActive} />
+              </View>
+              {showLabel ? (
+                presentation.titleState === "loading" ? (
+                  <View
+                    style={[
+                      styles.tabLabelSkeleton,
+                      showCloseButton && styles.tabLabelSkeletonWithCloseButton,
+                    ]}
+                  />
+                ) : (
+                  <Text
+                    style={[
+                      styles.tabLabel,
+                      isActive && styles.tabLabelActive,
+                      showCloseButton && styles.tabLabelWithCloseButton,
+                    ]}
+                    selectable={false}
+                    numberOfLines={1}
+                    ellipsizeMode="tail"
+                  >
+                    {presentation.label}
+                  </Text>
+                )
+              ) : null}
+            </View>
+
+            {showCloseButton ? (
+              <Pressable
+                testID={getCloseButtonTestId(tab)}
+                disabled={isClosingTab}
+                onHoverIn={() => {
+                  setHoveredTabKey(tab.key);
+                  setHoveredCloseTabKey(tab.key);
+                }}
+                onHoverOut={() => {
+                  setHoveredTabKey((current) => (current === tab.key ? null : current));
+                  setHoveredCloseTabKey((current) => (current === tab.key ? null : current));
+                }}
+                onPress={(event) => {
+                  event.stopPropagation?.();
+                  void onCloseTab(tab.tabId);
+                }}
+                style={({ hovered, pressed }) => [
+                  styles.tabCloseButton,
+                  styles.tabCloseButtonShown,
+                  (hovered || pressed) && styles.tabCloseButtonActive,
+                ]}
+              >
+                {({ hovered, pressed }) =>
+                  isClosingTab ? (
+                    <ActivityIndicator
+                      size={12}
+                      color={hovered || pressed ? theme.colors.foreground : theme.colors.foregroundMuted}
+                    />
+                  ) : (
+                    <X
+                      size={12}
+                      color={hovered || pressed ? theme.colors.foreground : theme.colors.foregroundMuted}
+                    />
+                  )
+                }
+              </Pressable>
+            ) : null}
+          </ContextMenuTrigger>
+        </TooltipTrigger>
+        <TooltipContent side="bottom" align="center" offset={8}>
+          <Text style={styles.newTabTooltipText}>{tooltipLabel}</Text>
+        </TooltipContent>
+      </Tooltip>
+
+      <ContextMenuContent align="start" width={DROPDOWN_WIDTH} testID={contextMenuTestId}>
+        {menuEntries.map((entry) =>
+          entry.kind === "separator" ? (
+            <ContextMenuSeparator key={entry.key} />
+          ) : (
+            <ContextMenuItem
+              key={entry.key}
+              testID={entry.testID}
+              disabled={entry.disabled}
+              destructive={entry.destructive}
+              onSelect={entry.onSelect}
+            >
+              {entry.label}
+            </ContextMenuItem>
+          )
+        )}
+      </ContextMenuContent>
+    </ContextMenu>
+  );
+}
+
 export function WorkspaceDesktopTabsRow({
   tabs,
   activeTabKey,
-  agentsById,
   normalizedServerId,
+  normalizedWorkspaceId,
   hoveredCloseTabKey,
   setHoveredTabKey,
   setHoveredCloseTabKey,
@@ -74,6 +305,43 @@ export function WorkspaceDesktopTabsRow({
   const { theme } = useUnistyles();
   const [tabsContainerWidth, setTabsContainerWidth] = useState<number>(0);
   const [tabsActionsWidth, setTabsActionsWidth] = useState<number>(0);
+  const [presentationsByKey, setPresentationsByKey] = useState<Map<string, WorkspaceTabPresentation>>(
+    () => new Map()
+  );
+
+  const handlePresentationChange = useCallback(
+    (tabKey: string, presentation: WorkspaceTabPresentation) => {
+      setPresentationsByKey((current) => {
+        const existing = current.get(tabKey);
+        if (
+          existing?.label === presentation.label &&
+          existing?.subtitle === presentation.subtitle &&
+          existing?.titleState === presentation.titleState &&
+          existing?.statusBucket === presentation.statusBucket &&
+          existing?.icon === presentation.icon
+        ) {
+          return current;
+        }
+        const next = new Map(current);
+        next.set(tabKey, presentation);
+        return next;
+      });
+    },
+    []
+  );
+
+  useEffect(() => {
+    setPresentationsByKey((current) => {
+      const next = new Map<string, WorkspaceTabPresentation>();
+      for (const tab of tabs) {
+        const presentation = current.get(tab.key);
+        if (presentation) {
+          next.set(tab.key, presentation);
+        }
+      }
+      return next.size === current.size ? current : next;
+    });
+  }, [tabs]);
 
   const handleTabsContainerLayout = useCallback((event: LayoutChangeEvent) => {
     const nextWidth = Math.round(event.nativeEvent.layout.width);
@@ -103,12 +371,14 @@ export function WorkspaceDesktopTabsRow({
   const tabLabelLengths = useMemo(
     () =>
       tabs.map((tab) => {
-        if (tab.kind === "agent" && tab.titleState === "loading") {
+        const presentation = presentationsByKey.get(tab.key);
+        if (presentation?.titleState === "loading") {
           return Math.max(1, Math.ceil(LOADING_TAB_LABEL_SKELETON_WIDTH / layoutMetrics.estimatedCharWidth));
         }
-        return tab.label.length;
+        const label = presentation?.label ?? getFallbackTabLabel(tab);
+        return label.length;
       }),
-    [layoutMetrics.estimatedCharWidth, tabs]
+    [layoutMetrics.estimatedCharWidth, presentationsByKey, tabs]
   );
 
   const { layout } = useWorkspaceTabLayout({
@@ -142,177 +412,49 @@ export function WorkspaceDesktopTabsRow({
           onDragEnd={onReorderTabs}
           renderItem={({ item: tab, index, dragHandleProps }) => {
             const isActive = tab.key === activeTabKey;
-            const tabAgent = tab.kind === "agent" ? agentsById.get(tab.agentId) ?? null : null;
             const isCloseHovered = hoveredCloseTabKey === tab.key;
             const isClosingAgent =
-              tab.kind === "agent" &&
+              tab.target.kind === "agent" &&
               isArchivingAgent({
                 serverId: normalizedServerId,
-                agentId: tab.agentId,
+                agentId: tab.target.agentId,
               });
             const isClosingTerminal =
-              tab.kind === "terminal" && killTerminalPending && killTerminalId === tab.terminalId;
+              tab.target.kind === "terminal" &&
+              killTerminalPending &&
+              killTerminalId === tab.target.terminalId;
             const isClosingTab = isClosingAgent || isClosingTerminal;
             const shouldShowCloseButton = layout.closeButtonPolicy === "all";
             const layoutItem = layout.items[index] ?? null;
             const resolvedTabWidth = layoutItem?.width ?? 150;
             const showLabel = layoutItem?.showLabel ?? true;
-            const presentation = deriveWorkspaceTabPresentation({ tab, agent: tabAgent });
-            const tooltipLabel =
-              tab.kind === "agent" && tab.titleState === "loading"
-                ? "Loading agent title"
-                : presentation.label;
-
-            const contextMenuTestId = `workspace-tab-context-${tab.key}`;
-            const menuEntries = buildWorkspaceTabMenuEntries({
-              surface: "desktop",
-              tab,
-              index,
-              tabCount: tabs.length,
-              menuTestIDBase: contextMenuTestId,
-              onCopyResumeCommand,
-              onCopyAgentId,
-              onCloseTab,
-              onCloseTabsBefore: onCloseTabsToLeft,
-              onCloseTabsAfter: onCloseTabsToRight,
-              onCloseOtherTabs,
-            });
 
             return (
-              <ContextMenu key={tab.key}>
+              <TabChip
-                <Tooltip delayDuration={400} enabledOnDesktop enabledOnMobile={false}>
+                key={tab.key}
-                  <TooltipTrigger asChild triggerRefProp="triggerRef">
+                tab={tab}
-                    <ContextMenuTrigger
+                index={index}
-                      testID={`workspace-tab-${tab.key}`}
+                tabCount={tabs.length}
-                      enabledOnMobile={false}
+                isActive={isActive}
-                      style={({ hovered, pressed }) => [
+                resolvedTabWidth={resolvedTabWidth}
-                        styles.tab,
+                showLabel={showLabel}
-                        {
+                showCloseButton={shouldShowCloseButton}
-                          minWidth: resolvedTabWidth,
+                isCloseHovered={isCloseHovered}
-                          width: resolvedTabWidth,
+                isClosingTab={isClosingTab}
-                          maxWidth: resolvedTabWidth,
+                normalizedServerId={normalizedServerId}
-                        },
+                normalizedWorkspaceId={normalizedWorkspaceId}
-                        isActive && styles.tabActive,
+                setHoveredTabKey={setHoveredTabKey}
-                        !isActive && (hovered || pressed || isCloseHovered) && styles.tabHovered,
+                setHoveredCloseTabKey={setHoveredCloseTabKey}
-                      ]}
+                onNavigateTab={onNavigateTab}
-                      onHoverIn={() => {
+                onCloseTab={onCloseTab}
-                        setHoveredTabKey(tab.key);
+                onCopyResumeCommand={onCopyResumeCommand}
-                      }}
+                onCopyAgentId={onCopyAgentId}
-                      onHoverOut={() => {
+                onCloseTabsToLeft={onCloseTabsToLeft}
-                        setHoveredTabKey((current) => (current === tab.key ? null : current));
+                onCloseTabsToRight={onCloseTabsToRight}
-                      }}
+                onCloseOtherTabs={onCloseOtherTabs}
-                      onPressIn={() => {
+                onPresentationChange={handlePresentationChange}
-                        onNavigateTab(tab.tabId);
+                dragHandleProps={dragHandleProps}
-                      }}
+              />
-                      onPress={() => {
-                        onNavigateTab(tab.tabId);
-                      }}
-                      accessibilityLabel={tooltipLabel}
-                    >
-                      <View
-                        {...(dragHandleProps?.attributes as any)}
-                        {...(dragHandleProps?.listeners as any)}
-                        ref={dragHandleProps?.setActivatorNodeRef}
-                        style={styles.tabHandle}
-                      >
-                        <View style={styles.tabIcon}>
-                          <WorkspaceTabIcon presentation={presentation} active={isActive} />
-                        </View>
-                        {showLabel ? (
-                          presentation.titleState === "loading" ? (
-                            <View
-                              style={[
-                                styles.tabLabelSkeleton,
-                                shouldShowCloseButton && styles.tabLabelSkeletonWithCloseButton,
-                              ]}
-                            />
-                          ) : (
-                            <Text
-                              style={[
-                                styles.tabLabel,
-                                isActive && styles.tabLabelActive,
-                                shouldShowCloseButton && styles.tabLabelWithCloseButton,
-                              ]}
-                              selectable={false}
-                              numberOfLines={1}
-                              ellipsizeMode="tail"
-                            >
-                              {tab.label}
-                            </Text>
-                          )
-                        ) : null}
-                      </View>
-
-                      {shouldShowCloseButton ? (
-                        <Pressable
-                          testID={
-                            tab.kind === "agent"
-                              ? `workspace-agent-close-${tab.agentId}`
-                              : tab.kind === "terminal"
-                                ? `workspace-terminal-close-${tab.terminalId}`
-                                : tab.kind === "draft"
-                                  ? `workspace-draft-close-${tab.draftId}`
-                                  : `workspace-file-close-${encodeFilePathForPathSegment(tab.filePath)}`
-                          }
-                          disabled={isClosingTab}
-                          onHoverIn={() => {
-                            setHoveredTabKey(tab.key);
-                            setHoveredCloseTabKey(tab.key);
-                          }}
-                          onHoverOut={() => {
-                            setHoveredTabKey((current) => (current === tab.key ? null : current));
-                            setHoveredCloseTabKey((current) => (current === tab.key ? null : current));
-                          }}
-                          onPress={(event) => {
-                            event.stopPropagation?.();
-                            void onCloseTab(tab.tabId);
-                          }}
-                          style={({ hovered, pressed }) => [
-                            styles.tabCloseButton,
-                            styles.tabCloseButtonShown,
-                            (hovered || pressed) && styles.tabCloseButtonActive,
-                          ]}
-                        >
-                          {({ hovered, pressed }) =>
-                            isClosingTab ? (
-                              <ActivityIndicator
-                                size={12}
-                                color={hovered || pressed ? theme.colors.foreground : theme.colors.foregroundMuted}
-                              />
-                            ) : (
-                              <X
-                                size={12}
-                                color={hovered || pressed ? theme.colors.foreground : theme.colors.foregroundMuted}
-                              />
-                            )
-                          }
-                        </Pressable>
-                      ) : null}
-                    </ContextMenuTrigger>
-                  </TooltipTrigger>
-                  <TooltipContent side="bottom" align="center" offset={8}>
-                    <Text style={styles.newTabTooltipText}>{tooltipLabel}</Text>
-                  </TooltipContent>
-                </Tooltip>
-
-                <ContextMenuContent align="start" width={DROPDOWN_WIDTH} testID={contextMenuTestId}>
-                  {menuEntries.map((entry) =>
-                    entry.kind === "separator" ? (
-                      <ContextMenuSeparator key={entry.key} />
-                    ) : (
-                      <ContextMenuItem
-                        key={entry.key}
-                        testID={entry.testID}
-                        disabled={entry.disabled}
-                        destructive={entry.destructive}
-                        onSelect={entry.onSelect}
-                      >
-                        {entry.label}
-                      </ContextMenuItem>
-                    )
-                  )}
-                </ContextMenuContent>
-              </ContextMenu>
             );
           }}
         />

packages/app/src/screens/workspace/workspace-screen.tsx

@@ -22,6 +22,7 @@ import {
 } from "lucide-react-native";
 import { GestureDetector } from "react-native-gesture-handler";
 import { StyleSheet, UnistylesRuntime, useUnistyles } from "react-native-unistyles";
+import invariant from "tiny-invariant";
 import { SidebarMenuToggle } from "@/components/headers/menu-header";
 import { HeaderToggleButton } from "@/components/headers/header-toggle-button";
 import { ScreenHeader } from "@/components/headers/screen-header";
@@ -40,8 +41,6 @@ import {
   TooltipTrigger,
 } from "@/components/ui/tooltip";
 import { ExplorerSidebar } from "@/components/explorer-sidebar";
-import { FilePane } from "@/components/file-pane";
-import { TerminalPane } from "@/components/terminal-pane";
 import { SourceControlPanelIcon } from "@/components/icons/source-control-panel-icon";
 import { WorkspaceGitActions } from "@/screens/workspace/workspace-git-actions";
 import { ExplorerSidebarAnimationProvider } from "@/contexts/explorer-sidebar-animation-context";
@@ -70,19 +69,18 @@ import {
   checkoutStatusQueryKey,
   type CheckoutStatusPayload,
 } from "@/hooks/use-checkout-status-query";
-import { AgentReadyScreen } from "@/screens/agent/agent-ready-screen";
+import { PaneProvider } from "@/panels/pane-context";
+import { ensurePanelsRegistered } from "@/panels/register-panels";
+import { getPanelRegistration } from "@/panels/panel-registry";
 import type { ListTerminalsResponse } from "@server/shared/messages";
 import { upsertTerminalListEntry } from "@/utils/terminal-list";
 import { confirmDialog } from "@/utils/confirm-dialog";
 import { useArchiveAgent } from "@/hooks/use-archive-agent";
 import { buildProviderCommand } from "@/utils/provider-command-templates";
 import { generateDraftId } from "@/stores/draft-keys";
-import { normalizeAgentSnapshot } from "@/utils/agent-snapshots";
-import { WorkspaceDraftAgentTab } from "@/screens/workspace/workspace-draft-agent-tab";
 import { WorkspaceDesktopTabsRow } from "@/screens/workspace/workspace-desktop-tabs-row";
 import {
-  deriveWorkspaceTabPresentation,
+  useWorkspaceTabPresentation,
-  type WorkspaceTabPresentation,
   WorkspaceTabIcon,
   WorkspaceTabOptionRow,
 } from "@/screens/workspace/workspace-tab-presentation";
@@ -145,14 +143,40 @@ function buildOpenIntentKey(input: {
   return `${input.serverId}:${input.workspaceId}:${openParam}`;
 }
 
+function getFallbackTabOptionLabel(tab: WorkspaceTabDescriptor): string {
+  if (tab.target.kind === "draft") {
+    return "New Agent";
+  }
+  if (tab.target.kind === "terminal") {
+    return "Terminal";
+  }
+  if (tab.target.kind === "file") {
+    return tab.target.path.split("/").filter(Boolean).pop() ?? tab.target.path;
+  }
+  return "Agent";
+}
+
+function getFallbackTabOptionDescription(tab: WorkspaceTabDescriptor): string {
+  if (tab.target.kind === "draft") {
+    return "New Agent";
+  }
+  if (tab.target.kind === "agent") {
+    return "Agent";
+  }
+  if (tab.target.kind === "terminal") {
+    return "Terminal";
+  }
+  return tab.target.path;
+}
+
 type MobileWorkspaceTabSwitcherProps = {
   tabs: WorkspaceTabDescriptor[];
   activeTabKey: string;
-  activeTabLabel: string;
+  activeTab: WorkspaceTabDescriptor | null;
-  activeTabPresentation: WorkspaceTabPresentation | null;
   tabSwitcherOptions: ComboboxOption[];
   tabByKey: Map<string, WorkspaceTabDescriptor>;
-  tabPresentationsByKey: Map<string, WorkspaceTabPresentation>;
+  normalizedServerId: string;
+  normalizedWorkspaceId: string;
   onSelectSwitcherTab: (key: string) => void;
   onSelectNewTabOption: (key: typeof NEW_TAB_AGENT_OPTION_ID) => void;
   onCopyResumeCommand: (agentId: string) => Promise<void> | void;
@@ -163,14 +187,167 @@ type MobileWorkspaceTabSwitcherProps = {
   onCloseOtherTabs: (tabId: string) => Promise<void> | void;
 };
 
+function MobileActiveTabTrigger({
+  activeTab,
+  normalizedServerId,
+  normalizedWorkspaceId,
+}: {
+  activeTab: WorkspaceTabDescriptor | null;
+  normalizedServerId: string;
+  normalizedWorkspaceId: string;
+}) {
+  if (!activeTab) {
+    return null;
+  }
+
+  return (
+    <ResolvedMobileActiveTabTrigger
+      activeTab={activeTab}
+      normalizedServerId={normalizedServerId}
+      normalizedWorkspaceId={normalizedWorkspaceId}
+    />
+  );
+}
+
+function ResolvedMobileActiveTabTrigger({
+  activeTab,
+  normalizedServerId,
+  normalizedWorkspaceId,
+}: {
+  activeTab: WorkspaceTabDescriptor;
+  normalizedServerId: string;
+  normalizedWorkspaceId: string;
+}) {
+  const presentation = useWorkspaceTabPresentation({
+    tab: activeTab,
+    serverId: normalizedServerId,
+    workspaceId: normalizedWorkspaceId,
+  });
+
+  return (
+    <>
+      <View style={styles.switcherTriggerIcon} testID="workspace-active-tab-icon">
+        <WorkspaceTabIcon presentation={presentation} active />
+      </View>
+
+      <Text style={styles.switcherTriggerText} numberOfLines={1}>
+        {presentation.titleState === "loading" ? "Loading..." : presentation.label}
+      </Text>
+    </>
+  );
+}
+
+function MobileWorkspaceTabOption({
+  tab,
+  tabIndex,
+  tabCount,
+  normalizedServerId,
+  normalizedWorkspaceId,
+  selected,
+  active,
+  onPress,
+  onCopyResumeCommand,
+  onCopyAgentId,
+  onCloseTab,
+  onCloseTabsAbove,
+  onCloseTabsBelow,
+  onCloseOtherTabs,
+}: {
+  tab: WorkspaceTabDescriptor;
+  tabIndex: number;
+  tabCount: number;
+  normalizedServerId: string;
+  normalizedWorkspaceId: string;
+  selected: boolean;
+  active: boolean;
+  onPress: () => void;
+  onCopyResumeCommand: (agentId: string) => Promise<void> | void;
+  onCopyAgentId: (agentId: string) => Promise<void> | void;
+  onCloseTab: (tabId: string) => Promise<void> | void;
+  onCloseTabsAbove: (tabId: string) => Promise<void> | void;
+  onCloseTabsBelow: (tabId: string) => Promise<void> | void;
+  onCloseOtherTabs: (tabId: string) => Promise<void> | void;
+}) {
+  const { theme } = useUnistyles();
+  const presentation = useWorkspaceTabPresentation({
+    tab,
+    serverId: normalizedServerId,
+    workspaceId: normalizedWorkspaceId,
+  });
+  const menuTestIDBase = `workspace-tab-menu-${tab.key}`;
+  const menuEntries = buildWorkspaceTabMenuEntries({
+    surface: "mobile",
+    tab,
+    index: tabIndex,
+    tabCount,
+    menuTestIDBase,
+    onCopyResumeCommand,
+    onCopyAgentId,
+    onCloseTab,
+    onCloseTabsBefore: onCloseTabsAbove,
+    onCloseTabsAfter: onCloseTabsBelow,
+    onCloseOtherTabs,
+  });
+
+  return (
+    <WorkspaceTabOptionRow
+      presentation={presentation}
+      selected={selected}
+      active={active}
+      onPress={onPress}
+      trailingAccessory={
+        <DropdownMenu>
+          <DropdownMenuTrigger
+            testID={`${menuTestIDBase}-trigger`}
+            accessibilityRole="button"
+            accessibilityLabel={`Open menu for ${presentation.label}`}
+            hitSlop={8}
+            style={({ open, pressed }) => [
+              styles.mobileTabMenuTrigger,
+              (open || pressed) && styles.mobileTabMenuTriggerActive,
+            ]}
+          >
+            <Ellipsis
+              size={theme.iconSize.sm}
+              color={theme.colors.foregroundMuted}
+            />
+          </DropdownMenuTrigger>
+          <DropdownMenuContent
+            side="bottom"
+            align="end"
+            width={220}
+            testID={menuTestIDBase}
+          >
+            {menuEntries.map((entry) =>
+              entry.kind === "separator" ? (
+                <DropdownMenuSeparator key={entry.key} />
+              ) : (
+                <DropdownMenuItem
+                  key={entry.key}
+                  testID={entry.testID}
+                  disabled={entry.disabled}
+                  destructive={entry.destructive}
+                  onSelect={entry.onSelect}
+                >
+                  {entry.label}
+                </DropdownMenuItem>
+              )
+            )}
+          </DropdownMenuContent>
+        </DropdownMenu>
+      }
+    />
+  );
+}
+
 const MobileWorkspaceTabSwitcher = memo(function MobileWorkspaceTabSwitcher({
   tabs,
   activeTabKey,
-  activeTabLabel,
+  activeTab,
-  activeTabPresentation,
   tabSwitcherOptions,
   tabByKey,
-  tabPresentationsByKey,
+  normalizedServerId,
+  normalizedWorkspaceId,
   onSelectSwitcherTab,
   onSelectNewTabOption,
   onCopyResumeCommand,
@@ -211,15 +388,11 @@ const MobileWorkspaceTabSwitcher = memo(function MobileWorkspaceTabSwitcher({
         onPress={() => setIsOpen(true)}
       >
         <View style={styles.switcherTriggerLeft}>
-          <View style={styles.switcherTriggerIcon} testID="workspace-active-tab-icon">
+          <MobileActiveTabTrigger
-            {activeTabPresentation ? (
+            activeTab={activeTab}
-              <WorkspaceTabIcon presentation={activeTabPresentation} active />
+            normalizedServerId={normalizedServerId}
-            ) : null}
+            normalizedWorkspaceId={normalizedWorkspaceId}
-          </View>
+          />
-
-          <Text style={styles.switcherTriggerText} numberOfLines={1}>
-            {activeTabLabel}
-          </Text>
         </View>
 
         <ChevronDown size={theme.iconSize.sm} color={theme.colors.foregroundMuted} />
@@ -264,74 +437,26 @@ const MobileWorkspaceTabSwitcher = memo(function MobileWorkspaceTabSwitcher({
           if (!tab) {
             return <View />;
           }
-          const presentation =
-            tabPresentationsByKey.get(option.id) ??
-            deriveWorkspaceTabPresentation({ tab });
           const tabIndex = tabIndexByKey.get(tab.key) ?? -1;
-          const menuTestIDBase = `workspace-tab-menu-${tab.key}`;
+          if (tabIndex < 0) {
-          const menuEntries =
+            return <View />;
-            tabIndex < 0
+          }
-              ? []
-              : buildWorkspaceTabMenuEntries({
-                  surface: "mobile",
-                  tab,
-                  index: tabIndex,
-                  tabCount: tabs.length,
-                  menuTestIDBase,
-                  onCopyResumeCommand,
-                  onCopyAgentId,
-                  onCloseTab,
-                  onCloseTabsBefore: onCloseTabsAbove,
-                  onCloseTabsAfter: onCloseTabsBelow,
-                  onCloseOtherTabs,
-                });
           return (
-            <WorkspaceTabOptionRow
+            <MobileWorkspaceTabOption
-              presentation={presentation}
+              tab={tab}
+              tabIndex={tabIndex}
+              tabCount={tabs.length}
+              normalizedServerId={normalizedServerId}
+              normalizedWorkspaceId={normalizedWorkspaceId}
               selected={selected}
               active={active}
               onPress={onPress}
-              trailingAccessory={
+              onCopyResumeCommand={onCopyResumeCommand}
-                <DropdownMenu>
+              onCopyAgentId={onCopyAgentId}
-                  <DropdownMenuTrigger
+              onCloseTab={onCloseTab}
-                    testID={`${menuTestIDBase}-trigger`}
+              onCloseTabsAbove={onCloseTabsAbove}
-                    accessibilityRole="button"
+              onCloseTabsBelow={onCloseTabsBelow}
-                    accessibilityLabel={`Open menu for ${presentation.label}`}
+              onCloseOtherTabs={onCloseOtherTabs}
-                    hitSlop={8}
-                    style={({ open, pressed }) => [
-                      styles.mobileTabMenuTrigger,
-                      (open || pressed) && styles.mobileTabMenuTriggerActive,
-                    ]}
-                  >
-                    <Ellipsis
-                      size={theme.iconSize.sm}
-                      color={theme.colors.foregroundMuted}
-                    />
-                  </DropdownMenuTrigger>
-                  <DropdownMenuContent
-                    side="bottom"
-                    align="end"
-                    width={220}
-                    testID={menuTestIDBase}
-                  >
-                    {menuEntries.map((entry) =>
-                      entry.kind === "separator" ? (
-                        <DropdownMenuSeparator key={entry.key} />
-                      ) : (
-                        <DropdownMenuItem
-                          key={entry.key}
-                          testID={entry.testID}
-                          disabled={entry.disabled}
-                          destructive={entry.destructive}
-                          onSelect={entry.onSelect}
-                        >
-                          {entry.label}
-                        </DropdownMenuItem>
-                      )
-                    )}
-                  </DropdownMenuContent>
-                </DropdownMenu>
-              }
             />
           );
         }}
@@ -340,6 +465,46 @@ const MobileWorkspaceTabSwitcher = memo(function MobileWorkspaceTabSwitcher({
   );
 });
 
+function PaneContent({
+  tab,
+  normalizedServerId,
+  normalizedWorkspaceId,
+  onOpenTab,
+  onCloseCurrentTab,
+  onRetargetCurrentTab,
+  onOpenWorkspaceFile,
+}: {
+  tab: WorkspaceTabDescriptor;
+  normalizedServerId: string;
+  normalizedWorkspaceId: string;
+  onOpenTab: (target: WorkspaceTabDescriptor["target"]) => void;
+  onCloseCurrentTab: () => void;
+  onRetargetCurrentTab: (target: WorkspaceTabDescriptor["target"]) => void;
+  onOpenWorkspaceFile: (filePath: string) => void;
+}) {
+  ensurePanelsRegistered();
+  const registration = getPanelRegistration(tab.kind);
+  invariant(registration, `No panel registration for kind: ${tab.kind}`);
+  const Component = registration.component;
+
+  return (
+    <PaneProvider
+      value={{
+        serverId: normalizedServerId,
+        workspaceId: normalizedWorkspaceId,
+        tabId: tab.tabId,
+        target: tab.target,
+        openTab: onOpenTab,
+        closeCurrentTab: onCloseCurrentTab,
+        retargetCurrentTab: onRetargetCurrentTab,
+        openFileInWorkspace: onOpenWorkspaceFile,
+      }}
+    >
+      <Component key={`${normalizedServerId}:${normalizedWorkspaceId}:${tab.tabId}`} />
+    </PaneProvider>
+  );
+}
+
 export function WorkspaceScreen({
   serverId,
   workspaceId,
@@ -841,8 +1006,6 @@ function WorkspaceScreenContent({
   const tabModel = useMemo(
     () =>
       deriveWorkspaceTabModel({
-        workspaceAgents,
-        terminals,
         tabs: uiTabs,
         tabOrder,
         focusedTabId,
@@ -857,7 +1020,7 @@ function WorkspaceScreenContent({
                   ? { kind: "file", path: unresolvedOpenIntent.path }
                   : null,
       }),
-    [focusedTabId, tabOrder, terminals, uiTabs, unresolvedOpenIntent, workspaceAgents]
+    [focusedTabId, tabOrder, uiTabs, unresolvedOpenIntent]
   );
   const activeTabId = tabModel.activeTabId;
 
@@ -976,33 +1139,17 @@ function WorkspaceScreenContent({
   }, [tabs]);
 
   const activeTabKey = activeTabId ?? "";
-  const tabPresentationsByKey = useMemo(() => {
-    const map = new Map<string, ReturnType<typeof deriveWorkspaceTabPresentation>>();
-    for (const tab of tabs) {
-      const agent = tab.kind === "agent" ? agentsById.get(tab.agentId) ?? null : null;
-      map.set(tab.key, deriveWorkspaceTabPresentation({ tab, agent }));
-    }
-    return map;
-  }, [agentsById, tabs]);
-  const activeTabPresentation = tabPresentationsByKey.get(activeTabKey) ?? null;
 
   const tabSwitcherOptions = useMemo(
     () =>
       tabs.map((tab) => ({
         id: tab.key,
-        label: tabPresentationsByKey.get(tab.key)?.titleState === "loading" ? "Loading..." : tab.label,
+        label: getFallbackTabOptionLabel(tab),
-        description: tab.subtitle,
+        description: getFallbackTabOptionDescription(tab),
       })),
-    [tabPresentationsByKey, tabs]
+    [tabs]
   );
 
-  const activeTabLabel = useMemo(() => {
-    if (activeTabPresentation?.titleState === "loading") {
-      return "Loading...";
-    }
-    return activeTabPresentation?.label ?? "Select tab";
-  }, [activeTabPresentation]);
-
   const handleCreateDraftTab = useCallback(() => {
     openWorkspaceDraftTab();
   }, [openWorkspaceDraftTab]);
@@ -1176,12 +1323,12 @@ function WorkspaceScreenContent({
       if (!tab) {
         return;
       }
-      if (tab.kind === "terminal") {
+      if (tab.target.kind === "terminal") {
-        await handleCloseTerminalTab({ tabId, terminalId: tab.terminalId });
+        await handleCloseTerminalTab({ tabId, terminalId: tab.target.terminalId });
         return;
       }
-      if (tab.kind === "agent") {
+      if (tab.target.kind === "agent") {
-        await handleCloseAgentTab({ tabId, agentId: tab.agentId });
+        await handleCloseAgentTab({ tabId, agentId: tab.target.agentId });
         return;
       }
       handleCloseDraftOrFileTab(tabId);
@@ -1434,114 +1581,59 @@ function WorkspaceScreenContent({
     handle: handleWorkspaceTabAction,
   });
 
-  const renderContent = () => {
+  const activeTabDescriptor = activeTab?.descriptor ?? null;
-    if (
+  const content = shouldRenderMissingWorkspaceDescriptor({
-      shouldRenderMissingWorkspaceDescriptor({
+    workspace: workspaceDescriptor,
-        workspace: workspaceDescriptor,
+    hasHydratedWorkspaces,
-        hasHydratedWorkspaces,
+  }) ? (
-      })
+    <View style={styles.emptyState}>
-    ) {
+      <ActivityIndicator color={theme.colors.foregroundMuted} />
-      return (
+    </View>
-        <View style={styles.emptyState}>
+  ) : !activeTabDescriptor ? (
-          <ActivityIndicator color={theme.colors.foregroundMuted} />
+    !hasHydratedAgents ? (
-        </View>
+      <View style={styles.emptyState}>
-      );
+        <ActivityIndicator color={theme.colors.foregroundMuted} />
-    }
+      </View>
-
-    const target = activeTab?.target ?? null;
-    if (!target) {
-      if (!hasHydratedAgents) {
-        return (
-          <View style={styles.emptyState}>
-            <ActivityIndicator color={theme.colors.foregroundMuted} />
-          </View>
-        );
-      }
-      return (
-        <View style={styles.emptyState}>
-          <Text style={styles.emptyStateText}>
-            No tabs are available yet. Use New tab to create an agent or terminal.
-          </Text>
-        </View>
-      );
-    }
-
-    if (target.kind === "draft") {
-      const tabId = activeTabId ?? target.draftId;
-      return (
-        <WorkspaceDraftAgentTab
-          key={`${normalizedServerId}:${normalizedWorkspaceId}:${tabId}`}
-          serverId={normalizedServerId}
-          workspaceId={normalizedWorkspaceId}
-          tabId={tabId}
-          draftId={target.draftId}
-          onOpenWorkspaceFile={handleOpenFileFromChat}
-          onCreated={(agentSnapshot) => {
-            const normalized = normalizeAgentSnapshot(agentSnapshot, normalizedServerId);
-            retargetWorkspaceTab({
-              serverId: normalizedServerId,
-              workspaceId: normalizedWorkspaceId,
-              tabId,
-              target: { kind: "agent", agentId: agentSnapshot.id },
-            });
-            useSessionStore.getState().setAgents(normalizedServerId, (prev) => {
-              const next = new Map(prev);
-              next.set(agentSnapshot.id, normalized);
-              return next;
-            });
-          }}
-        />
-      );
-    }
-
-    if (target.kind === "agent") {
-      return (
-        <AgentReadyScreen
-          key={`${normalizedServerId}:${normalizedWorkspaceId}:${target.agentId}`}
-          serverId={normalizedServerId}
-          agentId={target.agentId}
-          showExplorerSidebar={false}
-          wrapWithExplorerSidebarProvider={false}
-          onOpenWorkspaceFile={handleOpenFileFromChat}
-        />
-      );
-    }
-
-    if (target.kind === "file") {
-      return (
-        <FilePane
-          serverId={normalizedServerId}
-          workspaceRoot={normalizedWorkspaceId}
-          filePath={target.path}
-        />
-      );
-    }
-
-    return isScreenFocused ? (
-      <TerminalPane
-        serverId={normalizedServerId}
-        cwd={normalizedWorkspaceId}
-        selectedTerminalId={target.terminalId}
-        onSelectedTerminalIdChange={(terminalId) => {
-          if (!terminalId) {
-            return;
-          }
-          const tabId = openOrFocusTab({
-            serverId: normalizedServerId,
-            workspaceId: normalizedWorkspaceId,
-            target: { kind: "terminal", terminalId },
-          });
-          if (tabId) {
-            navigateToTabId(tabId);
-          }
-        }}
-        hideHeader
-        manageTerminalDirectorySubscription={false}
-      />
     ) : (
-      <View style={styles.contentPlaceholder} />
+      <View style={styles.emptyState}>
-    );
+        <Text style={styles.emptyStateText}>
-  };
+          No tabs are available yet. Use New tab to create an agent or terminal.
+        </Text>
+      </View>
+    )
+  ) : (
+    <PaneContent
+      tab={activeTabDescriptor}
+      normalizedServerId={normalizedServerId}
+      normalizedWorkspaceId={normalizedWorkspaceId}
+      onOpenTab={(target) => {
+        const tabId = openOrFocusTab({
+          serverId: normalizedServerId,
+          workspaceId: normalizedWorkspaceId,
+          target,
+        });
+        if (tabId) {
+          navigateToTabId(tabId);
+        }
+      }}
+      onCloseCurrentTab={() => {
+        if (activeTabDescriptor.tabId) {
+          void handleCloseTabById(activeTabDescriptor.tabId);
+        }
+      }}
+      onRetargetCurrentTab={(target) => {
+        retargetWorkspaceTab({
+          serverId: normalizedServerId,
+          workspaceId: normalizedWorkspaceId,
+          tabId: activeTabDescriptor.tabId,
+          target,
+        });
+      }}
+      onOpenWorkspaceFile={(filePath) => {
+        handleOpenFileFromChat({ filePath });
+      }}
+    />
+  );
 
   return (
     <View style={[styles.container, { backgroundColor: mainBackgroundColor }]}>
@@ -1728,11 +1820,11 @@ function WorkspaceScreenContent({
             <MobileWorkspaceTabSwitcher
               tabs={tabs}
               activeTabKey={activeTabKey}
-              activeTabLabel={activeTabLabel}
+              activeTab={activeTabDescriptor}
-              activeTabPresentation={activeTabPresentation}
               tabSwitcherOptions={tabSwitcherOptions}
               tabByKey={tabByKey}
-              tabPresentationsByKey={tabPresentationsByKey}
+              normalizedServerId={normalizedServerId}
+              normalizedWorkspaceId={normalizedWorkspaceId}
               onSelectSwitcherTab={handleSelectSwitcherTab}
               onSelectNewTabOption={handleSelectNewTabOption}
               onCopyResumeCommand={handleCopyResumeCommand}
@@ -1746,8 +1838,8 @@ function WorkspaceScreenContent({
             <WorkspaceDesktopTabsRow
               tabs={tabs}
               activeTabKey={activeTabKey}
-              agentsById={agentsById}
               normalizedServerId={normalizedServerId}
+              normalizedWorkspaceId={normalizedWorkspaceId}
               hoveredCloseTabKey={hoveredCloseTabKey}
               setHoveredTabKey={setHoveredTabKey}
               setHoveredCloseTabKey={setHoveredCloseTabKey}
@@ -1770,10 +1862,10 @@ function WorkspaceScreenContent({
           <View style={styles.centerContent}>
             {isMobile ? (
               <GestureDetector gesture={explorerOpenGesture} touchAction="pan-y">
-                <View style={styles.content}>{renderContent()}</View>
+                <View style={styles.content}>{content}</View>
               </GestureDetector>
             ) : (
-              <View style={styles.content}>{renderContent()}</View>
+              <View style={styles.content}>{content}</View>
             )}
           </View>
         </View>

packages/app/src/screens/workspace/workspace-tab-menu.test.ts

@@ -7,11 +7,7 @@ function createAgentTab(): WorkspaceTabDescriptor {
     key: "agent_123",
     tabId: "agent_123",
     kind: "agent",
-    agentId: "agent-123",
+    target: { kind: "agent", agentId: "agent-123" },
-    provider: "codex",
-    label: "Agent 123",
-    subtitle: "/repo",
-    titleState: "ready",
   };
 }
 
@@ -84,9 +80,7 @@ describe("buildWorkspaceTabMenuEntries", () => {
         key: "draft_123",
         tabId: "draft_123",
         kind: "draft",
-        draftId: "draft_123",
+        target: { kind: "draft", draftId: "draft_123" },
-        label: "New agent",
-        subtitle: "/repo",
       },
       index: 0,
       tabCount: 1,

packages/app/src/screens/workspace/workspace-tab-menu.ts

@@ -68,14 +68,15 @@ export function buildWorkspaceTabMenuEntries(
   const isOnlyTab = tabCount <= 1;
   const entries: WorkspaceTabMenuEntry[] = [];
 
-  if (tab.kind === "agent") {
+  if (tab.target.kind === "agent") {
+    const { agentId } = tab.target;
     entries.push({
       kind: "item",
       key: "copy-resume-command",
       label: "Copy resume command",
       testID: `${menuTestIDBase}-copy-resume-command`,
       onSelect: () => {
-        void onCopyResumeCommand(tab.agentId);
+        void onCopyResumeCommand(agentId);
       },
     });
     entries.push({
@@ -84,7 +85,7 @@ export function buildWorkspaceTabMenuEntries(
       label: "Copy agent id",
       testID: `${menuTestIDBase}-copy-agent-id`,
       onSelect: () => {
-        void onCopyAgentId(tab.agentId);
+        void onCopyAgentId(agentId);
       },
     });
     entries.push({

packages/app/src/screens/workspace/workspace-tab-model.test.ts

@@ -1,85 +1,9 @@
 import { describe, expect, it } from "vitest";
-import type { Agent } from "@/stores/session-store";
 import { deriveWorkspaceTabModel } from "@/screens/workspace/workspace-tab-model";
 import type { WorkspaceTab } from "@/stores/workspace-tabs-store";
 
-function makeAgent(input: {
-  id: string;
-  provider?: Agent["provider"];
-  title?: string | null;
-  createdAt?: Date;
-  lastActivityAt?: Date;
-  requiresAttention?: boolean;
-  attentionReason?: Agent["attentionReason"];
-}): Agent {
-  const createdAt = input.createdAt ?? new Date("2026-03-04T00:00:00.000Z");
-  const lastActivityAt = input.lastActivityAt ?? createdAt;
-  return {
-    serverId: "srv",
-    id: input.id,
-    provider: input.provider ?? "codex",
-    status: "idle",
-    createdAt,
-    updatedAt: createdAt,
-    lastUserMessageAt: null,
-    lastActivityAt,
-    capabilities: {
-      supportsStreaming: true,
-      supportsSessionPersistence: true,
-      supportsDynamicModes: true,
-      supportsMcpServers: true,
-      supportsReasoningStream: true,
-      supportsToolInvocations: true,
-    },
-    currentModeId: null,
-    availableModes: [],
-    pendingPermissions: [],
-    persistence: null,
-    runtimeInfo: {
-      provider: input.provider ?? "codex",
-      sessionId: null,
-    },
-    title: input.title ?? null,
-    cwd: "/repo/worktree",
-    model: null,
-    thinkingOptionId: null,
-    labels: {},
-    requiresAttention: input.requiresAttention ?? false,
-    attentionReason: input.attentionReason ?? null,
-    attentionTimestamp: null,
-    archivedAt: null,
-  };
-}
-
 describe("deriveWorkspaceTabModel", () => {
-  it("derives agent and terminal tabs from domain state, not UI membership", () => {
+  it("keeps normalized tabs in stored order and preserves targets", () => {
-    const model = deriveWorkspaceTabModel({
-      workspaceAgents: [
-        makeAgent({ id: "agent-a", title: "Build API" }),
-        makeAgent({ id: "agent-b", title: "" }),
-      ],
-      terminals: [{ id: "term-1", name: "shell" }],
-      tabs: [
-        { tabId: "agent_agent-a", target: { kind: "agent", agentId: "agent-a" }, createdAt: 1 },
-        { tabId: "agent_agent-b", target: { kind: "agent", agentId: "agent-b" }, createdAt: 2 },
-        { tabId: "terminal_term-1", target: { kind: "terminal", terminalId: "term-1" }, createdAt: 3 },
-      ],
-      tabOrder: [],
-    });
-
-    expect(model.tabs.map((tab) => tab.descriptor.tabId)).toEqual([
-      "agent_agent-a",
-      "agent_agent-b",
-      "terminal_term-1",
-    ]);
-    const firstAgent = model.tabs[0]?.descriptor;
-    const secondAgent = model.tabs[1]?.descriptor;
-    expect(firstAgent?.kind === "agent" ? firstAgent.titleState : null).toBe("ready");
-    expect(secondAgent?.kind === "agent" ? secondAgent.titleState : null).toBe("loading");
-    expect(secondAgent?.label).toBe("");
-  });
-
-  it("keeps draft and file tabs as explicit UI tabs", () => {
     const uiTabs: WorkspaceTab[] = [
       {
         tabId: "draft_123",
@@ -91,26 +15,33 @@ describe("deriveWorkspaceTabModel", () => {
         target: { kind: "file", path: "/repo/worktree/README.md" },
         createdAt: 2,
       },
+      {
+        tabId: "agent_agent-a",
+        target: { kind: "agent", agentId: "agent-a" },
+        createdAt: 3,
+      },
     ];
 
     const model = deriveWorkspaceTabModel({
-      workspaceAgents: [makeAgent({ id: "agent-a", title: "A" })],
+      tabs: uiTabs,
-      terminals: [],
-      tabs: [
-        ...uiTabs,
-        { tabId: "agent_agent-a", target: { kind: "agent", agentId: "agent-a" }, createdAt: 3 },
-      ],
       tabOrder: ["draft_123", "agent_agent-a", "file_/repo/worktree/README.md"],
     });
 
-    expect(model.tabs.map((tab) => tab.descriptor.kind)).toEqual(["draft", "agent", "file"]);
+    expect(model.tabs.map((tab) => tab.descriptor.tabId)).toEqual([
-    expect(model.tabs[0]?.descriptor.label).toBe("New Agent");
+      "draft_123",
+      "agent_agent-a",
+      "file_/repo/worktree/README.md",
+    ]);
+    expect(model.tabs[0]?.descriptor.target).toEqual({ kind: "draft", draftId: "draft_123" });
+    expect(model.tabs[1]?.descriptor.target).toEqual({ kind: "agent", agentId: "agent-a" });
+    expect(model.tabs[2]?.descriptor.target).toEqual({
+      kind: "file",
+      path: "/repo/worktree/README.md",
+    });
   });
 
-  it("applies stored order and appends newly-derived tabs deterministically", () => {
+  it("applies stored order and appends unordered tabs deterministically", () => {
     const model = deriveWorkspaceTabModel({
-      workspaceAgents: [makeAgent({ id: "agent-a" }), makeAgent({ id: "agent-b" })],
-      terminals: [{ id: "term-1", name: "zsh" }],
       tabs: [
         { tabId: "agent_agent-a", target: { kind: "agent", agentId: "agent-a" }, createdAt: 1 },
         { tabId: "agent_agent-b", target: { kind: "agent", agentId: "agent-b" }, createdAt: 2 },
@@ -128,8 +59,6 @@ describe("deriveWorkspaceTabModel", () => {
 
   it("uses focused tab when present, otherwise falls back to first tab", () => {
     const base: Parameters<typeof deriveWorkspaceTabModel>[0] = {
-      workspaceAgents: [makeAgent({ id: "agent-a" }), makeAgent({ id: "agent-b" })],
-      terminals: [],
       tabs: [
         { tabId: "agent_agent-a", target: { kind: "agent", agentId: "agent-a" }, createdAt: 1 },
         { tabId: "agent_agent-b", target: { kind: "agent", agentId: "agent-b" }, createdAt: 2 },
@@ -144,18 +73,11 @@ describe("deriveWorkspaceTabModel", () => {
       }).activeTabId
     ).toBe("agent_agent-b");
 
-    expect(
+    expect(deriveWorkspaceTabModel(base).activeTabId).toBe("agent_agent-a");
-      deriveWorkspaceTabModel({
-        ...base,
-        focusedTabId: "agent_agent-b",
-      }).activeTabId
-    ).toBe("agent_agent-b");
   });
 
   it("prefers the route-selected target over stale focused tab state", () => {
     const model = deriveWorkspaceTabModel({
-      workspaceAgents: [makeAgent({ id: "agent-a" }), makeAgent({ id: "agent-b" })],
-      terminals: [],
       tabs: [
         { tabId: "agent_agent-a", target: { kind: "agent", agentId: "agent-a" }, createdAt: 1 },
         { tabId: "agent_agent-b", target: { kind: "agent", agentId: "agent-b" }, createdAt: 2 },
@@ -166,59 +88,11 @@ describe("deriveWorkspaceTabModel", () => {
     });
 
     expect(model.activeTabId).toBe("agent_agent-b");
-    expect(model.activeTab?.target).toEqual({ kind: "agent", agentId: "agent-b" });
+    expect(model.activeTab?.descriptor.target).toEqual({ kind: "agent", agentId: "agent-b" });
   });
 
-  it("re-resolves active content for a new workspace when prior focused tab is not available", () => {
+  it("keeps retargeted tab ids stable while matching upgraded targets", () => {
     const model = deriveWorkspaceTabModel({
-      workspaceAgents: [makeAgent({ id: "workspace-b-agent", title: "B" })],
-      terminals: [],
-      tabs: [
-        {
-          tabId: "agent_workspace-b-agent",
-          target: { kind: "agent", agentId: "workspace-b-agent" },
-          createdAt: 1,
-        },
-      ],
-      tabOrder: ["agent_workspace-b-agent"],
-      focusedTabId: "agent_workspace-a-agent",
-    });
-
-    expect(model.activeTabId).toBe("agent_workspace-b-agent");
-    expect(model.activeTab?.target).toEqual({
-      kind: "agent",
-      agentId: "workspace-b-agent",
-    });
-  });
-
-  it("does not materialize tabs absent from workspace tab membership", () => {
-    const offending = makeAgent({
-      id: "offender",
-      title: "Needs permission",
-      requiresAttention: true,
-      attentionReason: "permission",
-    });
-
-    const model = deriveWorkspaceTabModel({
-      workspaceAgents: [offending],
-      terminals: [],
-      tabs: [
-        {
-          tabId: "draft_123",
-          target: { kind: "draft", draftId: "draft_123" },
-          createdAt: 1,
-        },
-      ],
-      tabOrder: ["draft_123"],
-    });
-
-    expect(model.tabs.some((tab) => tab.descriptor.tabId === "agent_offender")).toBe(false);
-  });
-
-  it("keeps retargeted agent tab id stable while upgrading descriptor data", () => {
-    const model = deriveWorkspaceTabModel({
-      workspaceAgents: [],
-      terminals: [],
       tabs: [
         {
           tabId: "draft_abc",
@@ -227,52 +101,35 @@ describe("deriveWorkspaceTabModel", () => {
         },
       ],
       tabOrder: ["draft_abc"],
-    });
-    const initial = model.tabs[0]?.descriptor;
-    expect(initial?.tabId).toBe("draft_abc");
-    expect(initial?.kind).toBe("agent");
-    if (initial?.kind === "agent") {
-      expect(initial.titleState).toBe("loading");
-      expect(initial.agentId).toBe("agent-1");
-    }
-
-    const upgraded = deriveWorkspaceTabModel({
-      workspaceAgents: [makeAgent({ id: "agent-1", title: "Ready title" })],
-      terminals: [],
-      tabs: [
-        {
-          tabId: "draft_abc",
-          target: { kind: "agent", agentId: "agent-1" },
-          createdAt: 1,
-        },
-      ],
-      tabOrder: ["draft_abc"],
-    });
-    const upgradedDescriptor = upgraded.tabs[0]?.descriptor;
-    expect(upgradedDescriptor?.tabId).toBe("draft_abc");
-    if (upgradedDescriptor?.kind === "agent") {
-      expect(upgradedDescriptor.titleState).toBe("ready");
-      expect(upgradedDescriptor.label).toBe("Ready title");
-    }
-  });
-
-  it("prefers a retargeted tab when the route selects its upgraded agent target", () => {
-    const model = deriveWorkspaceTabModel({
-      workspaceAgents: [makeAgent({ id: "agent-1", title: "Ready title" })],
-      terminals: [],
-      tabs: [
-        {
-          tabId: "draft_abc",
-          target: { kind: "agent", agentId: "agent-1" },
-          createdAt: 1,
-        },
-      ],
-      tabOrder: ["draft_abc"],
-      focusedTabId: "some_other_tab",
       preferredTarget: { kind: "agent", agentId: "agent-1" },
     });
 
     expect(model.activeTabId).toBe("draft_abc");
     expect(model.activeTab?.descriptor.tabId).toBe("draft_abc");
+    expect(model.activeTab?.descriptor.target).toEqual({ kind: "agent", agentId: "agent-1" });
+  });
+
+  it("normalizes file paths and discards invalid tabs", () => {
+    const model = deriveWorkspaceTabModel({
+      tabs: [
+        {
+          tabId: "file_path",
+          target: { kind: "file", path: "\\repo\\worktree\\README.md" },
+          createdAt: 1,
+        },
+        {
+          tabId: "",
+          target: { kind: "agent", agentId: "agent-a" },
+          createdAt: 2,
+        },
+      ],
+      tabOrder: [],
+    });
+
+    expect(model.tabs).toHaveLength(1);
+    expect(model.tabs[0]?.descriptor.target).toEqual({
+      kind: "file",
+      path: "/repo/worktree/README.md",
+    });
   });
 });

packages/app/src/screens/workspace/workspace-tab-model.ts

@@ -1,22 +1,15 @@
-import type { Agent } from "@/stores/session-store";
 import type { WorkspaceTab, WorkspaceTabTarget } from "@/stores/workspace-tabs-store";
 import type { WorkspaceTabDescriptor } from "@/screens/workspace/workspace-tabs-types";
 
-type TerminalLike = {
+export interface WorkspaceDerivedTab {
-  id: string;
-  name?: string | null;
-};
-
-export type WorkspaceDerivedTab = {
   descriptor: WorkspaceTabDescriptor;
-  target: WorkspaceTabTarget;
+}
-};
 
-export type WorkspaceTabModel = {
+export interface WorkspaceTabModel {
   tabs: WorkspaceDerivedTab[];
   activeTabId: string | null;
   activeTab: WorkspaceDerivedTab | null;
-};
+}
 
 function trimNonEmpty(value: string | null | undefined): string | null {
   if (typeof value !== "string") {
@@ -45,33 +38,6 @@ function tabTargetsEqual(left: WorkspaceTabTarget, right: WorkspaceTabTarget): b
   return false;
 }
 
-function formatProviderLabel(provider: Agent["provider"]): string {
-  if (provider === "claude") {
-    return "Claude";
-  }
-  if (provider === "codex") {
-    return "Codex";
-  }
-  if (!provider) {
-    return "Agent";
-  }
-  return provider.charAt(0).toUpperCase() + provider.slice(1);
-}
-
-function resolveWorkspaceAgentTabLabel(title: string | null | undefined): string | null {
-  if (typeof title !== "string") {
-    return null;
-  }
-  const normalized = title.trim();
-  if (!normalized) {
-    return null;
-  }
-  if (normalized.toLowerCase() === "new agent") {
-    return null;
-  }
-  return normalized;
-}
-
 function normalizeWorkspaceTab(tab: WorkspaceTab): WorkspaceTab | null {
   if (!tab || typeof tab !== "object") {
     return null;
@@ -144,16 +110,12 @@ export function buildWorkspaceTabId(target: WorkspaceTabTarget): string {
 }
 
 export function deriveWorkspaceTabModel(input: {
-  workspaceAgents: Agent[];
-  terminals: TerminalLike[];
   tabs: WorkspaceTab[];
   tabOrder: string[];
   focusedTabId?: string | null;
   preferredTarget?: WorkspaceTabTarget | null;
 }): WorkspaceTabModel {
   const tabsById = new Map<string, WorkspaceDerivedTab>();
-  const agentsById = new Map(input.workspaceAgents.map((agent) => [agent.id, agent]));
-  const terminalsById = new Map(input.terminals.map((terminal) => [terminal.id, terminal]));
 
   const normalizedTabs = input.tabs
     .map((tab) => normalizeWorkspaceTab(tab))
@@ -161,72 +123,14 @@ export function deriveWorkspaceTabModel(input: {
     .sort((left, right) => left.createdAt - right.createdAt);
 
   for (const tab of normalizedTabs) {
-    if (tab.target.kind === "draft") {
+    tabsById.set(tab.tabId, {
-      tabsById.set(tab.tabId, {
+      descriptor: {
+        key: tab.tabId,
+        tabId: tab.tabId,
+        kind: tab.target.kind,
         target: tab.target,
-        descriptor: {
+      },
-          key: tab.tabId,
+    });
-          tabId: tab.tabId,
-          kind: "draft",
-          draftId: tab.target.draftId,
-          label: "New Agent",
-          subtitle: "New Agent",
-        },
-      });
-      continue;
-    }
-
-    if (tab.target.kind === "agent") {
-      const agent = agentsById.get(tab.target.agentId) ?? null;
-      const label = resolveWorkspaceAgentTabLabel(agent?.title);
-      const provider = agent?.provider ?? "codex";
-      tabsById.set(tab.tabId, {
-        target: tab.target,
-        descriptor: {
-          key: tab.tabId,
-          tabId: tab.tabId,
-          kind: "agent",
-          agentId: tab.target.agentId,
-          provider,
-          label: label ?? "",
-          subtitle: `${formatProviderLabel(provider)} agent`,
-          titleState: label ? "ready" : "loading",
-        },
-      });
-      continue;
-    }
-
-    if (tab.target.kind === "terminal") {
-      const terminal = terminalsById.get(tab.target.terminalId) ?? null;
-      tabsById.set(tab.tabId, {
-        target: tab.target,
-        descriptor: {
-          key: tab.tabId,
-          tabId: tab.tabId,
-          kind: "terminal",
-          terminalId: tab.target.terminalId,
-          label: trimNonEmpty(terminal?.name ?? null) ?? "Terminal",
-          subtitle: "Terminal",
-        },
-      });
-      continue;
-    }
-
-    if (tab.target.kind === "file") {
-      const filePath = tab.target.path;
-      const fileName = filePath.split("/").filter(Boolean).pop() ?? filePath;
-      tabsById.set(tab.tabId, {
-        target: tab.target,
-        descriptor: {
-          key: tab.tabId,
-          tabId: tab.tabId,
-          kind: "file",
-          filePath,
-          label: fileName,
-          subtitle: filePath,
-        },
-      });
-    }
   }
 
   const orderedTabIds: string[] = [];
@@ -260,7 +164,7 @@ export function deriveWorkspaceTabModel(input: {
       return null;
     }
     const matchingTab =
-      tabs.find((tab) => tabTargetsEqual(tab.target, preferredTarget)) ?? null;
+      tabs.find((tab) => tabTargetsEqual(tab.descriptor.target, preferredTarget)) ?? null;
     return matchingTab?.descriptor.tabId ?? buildWorkspaceTabId(preferredTarget);
   })();
 
@@ -268,8 +172,8 @@ export function deriveWorkspaceTabModel(input: {
     preferredTabId && openTabIds.has(preferredTabId)
       ? preferredTabId
       : focusedTabId && openTabIds.has(focusedTabId)
-      ? focusedTabId
+        ? focusedTabId
-      : tabs[0]?.descriptor.tabId ?? null;
+        : tabs[0]?.descriptor.tabId ?? null;
 
   const activeTab = activeTabId
     ? tabs.find((tab) => tab.descriptor.tabId === activeTabId) ?? null

packages/app/src/screens/workspace/workspace-tab-presentation.tsx

@@ -1,50 +1,47 @@
 import type { ReactElement, ReactNode } from "react";
 import { Pressable, Text, View } from "react-native";
-import { Bot, Check, FileText, Pencil, Terminal } from "lucide-react-native";
+import { Check } from "lucide-react-native";
 import { StyleSheet, useUnistyles } from "react-native-unistyles";
-import { ClaudeIcon } from "@/components/icons/claude-icon";
+import invariant from "tiny-invariant";
-import { CodexIcon } from "@/components/icons/codex-icon";
 import { SyncedLoader } from "@/components/synced-loader";
-import type { Agent } from "@/stores/session-store";
+import { ensurePanelsRegistered } from "@/panels/register-panels";
+import { getPanelRegistration } from "@/panels/panel-registry";
 import type { WorkspaceTabDescriptor } from "@/screens/workspace/workspace-tabs-types";
-import {
+import type { SidebarStateBucket } from "@/utils/sidebar-agent-state";
-  deriveSidebarStateBucket,
-  type SidebarStateBucket,
-} from "@/utils/sidebar-agent-state";
 import { getStatusDotColor } from "@/utils/status-dot-color";
 import { shouldRenderSyncedStatusLoader } from "@/utils/status-loader";
 
-export type WorkspaceTabPresentation = {
+export interface WorkspaceTabPresentation {
   key: string;
   kind: WorkspaceTabDescriptor["kind"];
   label: string;
   subtitle: string;
   titleState: "ready" | "loading";
-  provider: Agent["provider"] | null;
+  icon: React.ComponentType<{ size: number; color: string }>;
   statusBucket: SidebarStateBucket | null;
-};
+}
 
-export function deriveWorkspaceTabPresentation(input: {
+export function useWorkspaceTabPresentation(input: {
   tab: WorkspaceTabDescriptor;
-  agent?: Agent | null;
+  serverId: string;
+  workspaceId: string;
 }): WorkspaceTabPresentation {
-  const { tab, agent = null } = input;
+  ensurePanelsRegistered();
+  const registration = getPanelRegistration(input.tab.kind);
+  invariant(registration, `No panel registration for kind: ${input.tab.kind}`);
+  const descriptor = registration.useDescriptor(input.tab.target, {
+    serverId: input.serverId,
+    workspaceId: input.workspaceId,
+  });
+
   return {
-    key: tab.key,
+    key: input.tab.key,
-    kind: tab.kind,
+    kind: input.tab.kind,
-    label: tab.label,
+    label: descriptor.label,
-    subtitle: tab.subtitle,
+    subtitle: descriptor.subtitle,
-    titleState: tab.kind === "agent" ? tab.titleState : "ready",
+    titleState: descriptor.titleState,
-    provider: tab.kind === "agent" ? tab.provider : null,
+    icon: descriptor.icon,
-    statusBucket:
+    statusBucket: descriptor.statusBucket,
-      tab.kind === "agent" && agent
-        ? deriveSidebarStateBucket({
-            status: agent.status,
-            pendingPermissionCount: agent.pendingPermissions.length,
-            requiresAttention: agent.requiresAttention,
-            attentionReason: agent.attentionReason,
-          })
-        : null,
   };
 }
 
@@ -74,49 +71,32 @@ export function WorkspaceTabIcon({
   const shouldShowLoader = shouldRenderSyncedStatusLoader({
     bucket: presentation.statusBucket,
   });
+  const Icon = presentation.icon;
 
-  if (presentation.kind === "agent") {
+  if (shouldShowLoader) {
-    if (shouldShowLoader) {
-      return (
-        <View style={[styles.agentIconWrapper, { width: size, height: size }]}>
-          <SyncedLoader size={size - 1} color={theme.colors.palette.amber[500]} />
-        </View>
-      );
-    }
-
     return (
       <View style={[styles.agentIconWrapper, { width: size, height: size }]}>
-        {presentation.provider === "claude" ? (
+        <SyncedLoader size={size - 1} color={theme.colors.palette.amber[500]} />
-          <ClaudeIcon size={size} color={iconColor} />
-        ) : presentation.provider === "codex" ? (
-          <CodexIcon size={size} color={iconColor} />
-        ) : (
-          <Bot size={size} color={iconColor} />
-        )}
-        {statusDotColor ? (
-          <View
-            style={[
-              styles.statusDot,
-              {
-                backgroundColor: statusDotColor,
-                borderColor: statusDotBorderColor ?? theme.colors.surface0,
-              },
-            ]}
-          />
-        ) : null}
       </View>
     );
   }
 
-  if (presentation.kind === "draft") {
+  return (
-    return <Pencil size={size} color={iconColor} />;
+    <View style={[styles.agentIconWrapper, { width: size, height: size }]}>
-  }
+      <Icon size={size} color={iconColor} />
-
+      {statusDotColor ? (
-  if (presentation.kind === "file") {
+        <View
-    return <FileText size={size} color={iconColor} />;
+          style={[
-  }
+            styles.statusDot,
-
+            {
-  return <Terminal size={size} color={iconColor} />;
+              backgroundColor: statusDotColor,
+              borderColor: statusDotBorderColor ?? theme.colors.surface0,
+            },
+          ]}
+        />
+      ) : null}
+    </View>
+  );
 }
 
 type WorkspaceTabOptionRowProps = {

packages/app/src/screens/workspace/workspace-tabs-types.ts

@@ -1,37 +1,8 @@
-import type { Agent } from "@/stores/session-store";
+import type { WorkspaceTabTarget } from "@/stores/workspace-tabs-store";
 
-export type WorkspaceTabDescriptor =
+export interface WorkspaceTabDescriptor {
-  | {
+  key: string;
-      key: string;
+  tabId: string;
-      tabId: string;
+  kind: WorkspaceTabTarget["kind"];
-      kind: "draft";
+  target: WorkspaceTabTarget;
-      draftId: string;
+}
-      label: string;
-      subtitle: string;
-    }
-  | {
-      key: string;
-      tabId: string;
-      kind: "agent";
-      agentId: string;
-      provider: Agent["provider"];
-      label: string;
-      subtitle: string;
-      titleState: "ready" | "loading";
-    }
-  | {
-      key: string;
-      tabId: string;
-      kind: "terminal";
-      terminalId: string;
-      label: string;
-      subtitle: string;
-    }
-  | {
-      key: string;
-      tabId: string;
-      kind: "file";
-      filePath: string;
-      label: string;
-      subtitle: string;
-    };