Chat Layout Modes

Home and Agent no longer persist a separate manual classic / modern layout preference. The layout is derived from the resource-list display mode.

Home

• topic.tab.display_mode = 'assistant' uses the classic layout: assistant rail on the left, chat in the center, topic list either in the left rail or the right pane depending on topic.tab.position.
• topic.tab.display_mode = 'time' uses the modern single-sidebar layout.

Agent

• agent.session.display_mode = 'agent' uses the classic layout: agent rail on the left, chat in the center, session list either in the left rail or the right pane depending on agent.session.position.
• agent.session.display_mode = 'time' or 'workdir' uses the modern single-sidebar layout.

State

• Display mode and topic/session position are stored as Preference data.
• topic.tab.show controls whether the left resource list is expanded.
• Classic-layout right-pane state is persisted independently per surface via useClassicLayoutRightPaneOpen(surface, { enabled, defaultOpen }): ui.chat.right_pane_open_override for Home and ui.agent.right_pane_open_override for Agent. A null override delegates to the page default: the pane opens when the topic/session list is positioned on the right in a main window. Explicit open/closed choices persist across page re-entry.
• Resource-list collapsed groups are stored per display mode in renderer persist cache.

Left Entity Rail

ResourceEntityRail (presentational, generic) + useResourceEntityRail (shared behavior) power the classic left rail. AssistantResourceList and AgentResourceList own data fetching, pins, deletion, icon display, and context menus.

• Home shows assistants; Agent shows agents.
• Only entities that already own topics/sessions are shown.
• The top action creates or selects an assistant/agent through the shared picker.
• Management entries live in the display/options menu, not as extra top rail entries.
• Pinned entities float into a pinned section; non-pinned entities are ordered by assistant/agent orderKey.

Right Resource Panel

When the topic/session position is right, the topic/session list is injected as the first resource tab through ResourcePaneProvider / useResourcePane.

• Home lists topics; Agent lists sessions.
• Lists are scoped to the current assistant/agent.
• When no explicit pane override exists, placing the topic/session list on the right opens both the left owner rail and the right resource list by default.
• Manually closing the right pane stores an explicit override, matching the left rail's re-entry behavior.
• The right panel shares the existing RightPanel chrome with branch, trace, files, status, and flow panels.
• Right-panel topic/session lists stay time-grouped and do not write the left list's display-mode collapse state.

Composer Entity Controls

In classic layout the left rail owns entity switching, so the composer hides the assistant/agent switcher while the classic entity rail is active.

• ChatComposer hides the assistant trigger when the assistant display mode is active.
• AgentComposer hides the agent trigger when the agent display mode is active.
• Classic layout adds a new conversation/work action to the composer controls when onCreateEmptyTopic / onCreateEmptySession is available.

Agent Workspace Control

Classic-layout agent chats keep the workspace control visible in the composer.

• Draft sessions keep the editable workspace selector.
• Persistent sessions can switch workspace only while the visible session is still empty.
• The data service rejects workspace updates once the session has messages.

Data Flow

No DataApi endpoint filters topics/sessions by entity. The entity rail and right panel read the same full-list source and filter in the frontend.

• Home uses useAssistantTopicsSource.
• Agent uses useAgentSessionsSource.
• Create/delete/rename/clear/move use the existing mutation and invalidate flow; after a mutation, both sides re-derive from the refreshed shared source.

Key Files

• src/renderer/components/chat/resourceList/ResourceEntityRail.tsx
• src/renderer/components/chat/resourceList/useResourceEntityRail.ts
• src/renderer/components/chat/resourceList/AssistantResourceList.tsx
• src/renderer/components/chat/resourceList/AgentResourceList.tsx
• src/renderer/components/chat/panes/Shell/resourcePane.tsx
• src/renderer/pages/home/HomePage.tsx
• src/renderer/pages/agents/AgentPage.tsx
• src/renderer/pages/agents/AgentChat.tsx