galaxy/specs/APP-3619/TECH.md

Tech Spec: Plugin Installation Fallback Modal

See specs/APP-3619/PRODUCT.md for the full product spec.

1. Install Instructions Data Model

plugin_manager/mod.rs

Add PluginInstallStep and PluginInstallInstructions structs. Replace the existing post_install_hint() trait method with install_instructions() -> &'static PluginInstallInstructions that returns all modal content for this agent.

pub(crate) struct PluginInstallStep {
    pub description: &'static str,
    pub command: &'static str,
}

pub(crate) struct PluginInstallInstructions {
    pub title: &'static str,
    pub subtitle: &'static str,
    pub steps: &'static [PluginInstallStep],
    pub success_toast: &'static str,
}

Each implementation uses LazyLock so the data is built once. Claude Code's steps are the in-session slash commands (/plugins marketplace add ..., /plugins install ..., /reload-plugins) since the user is already in a running session.

The existing post_install_hint is removed. The auto-install success toast reads from install_instructions().success_toast.

2. Modal View

New file: workspace/view/plugin_install_modal.rs, following the CodexModal pattern (standalone view, centered overlay, backdrop, Escape to close).

View struct

pub struct PluginInstallModal {
    agent: Option<CLIAgent>,
    close_button_mouse_state: MouseStateHandle,
    step_code_handles: Vec<CodeSnippetButtonHandles>,
}

agent is Option so the view can be constructed once in workspace init and updated via set_agent() before each open. All MouseStateHandles are stored in the struct (not created inline during render). Copying a command shows a "Copied to clipboard" ephemeral toast via ToastStack. The modal uses Dismiss to close on outside click.

Code block rendering

Reuse render_code_block_plain (ai/blocklist/code_block.rs:117) with CodeBlockOptions — the same component already used by cloud_setup_guide_view.rs:393 for its step-by-step CLI guide. Each step gets on_copy + a CodeSnippetButtonHandles.

Per-agent extensibility

render() dispatches to per-agent render functions that compose shared helpers (modal shell, numbered step layout, code blocks). Adding a new agent means adding a render function + PluginInstallInstructions implementation.

Actions & Events

enum PluginInstallModalAction { Close, CopyCommand(usize) }
enum PluginInstallModalEvent { Close }

3. Workspace Wiring

Follows the standard modal pattern (like CodexModal at workspace/view.rs:817,1573,12878,18110):

• is_plugin_install_modal_open on WorkspaceState (add to is_any_non_palette_modal_open and close_all_modals in workspace/util.rs)
• plugin_install_modal: ViewHandle<PluginInstallModal> on Workspace
• open_plugin_install_modal(agent) sets the agent, flips the bool, focuses the modal
• Rendered conditionally in the workspace render method's modal stack

4. Event Plumbing: Footer → Workspace

New ShowPluginInstallModal(CLIAgent) variant propagated through the standard event chain:

AgentInputFooterEvent (mod.rs:1325) → Input::Event (input.rs:1039) → TerminalView::Event → pane_group::Event → Workspace handler

Follows the existing OpenAutoReloadModal pattern (view.rs:18411, workspace/view.rs:10182).

5. Remote Session Detection

CLIAgentSession has an is_remote: bool field set at session creation from TerminalView::active_session_is_local(). This uses SessionType::WarpifiedRemote and IsLegacySSHSession — the same logic as the SSH host chip (context_chips/builtins.rs:76).

This avoids relying on terminal_model.is_ssh_block() (which only tracks the pre-warpification login phase) or is_warpified_ssh() (which misses legacy SSH). The is_remote flag is threaded through set_session and register_listener at all call sites in terminal/view.rs.

6. Two-Mode Chip

agent_input_footer/mod.rs — the install chip has two modes based on whether auto-install is viable.

Mode selection

should_use_manual_install_mode(&self, app) returns true when:

• plugin_install_failed is set (auto-install already failed this session), OR
• session.is_remote is true (checked via CLIAgentSessionsModel)

Remote visibility fix

should_show_install_plugin_button checks session.is_remote — when true, skips the local is_installed() filesystem check and relies solely on listener presence.

Two buttons

ActionButton doesn't support changing label/icon after construction, so we create two ActionButton views and conditionally render the right one:

• Auto-install (existing install_plugin_button): "Install Warp plugin" / Icon::Download → triggers handle_install_plugin
• Manual (new plugin_instructions_button): "Plugin install instructions" / Icon::Info → emits ShowPluginInstallModal

In render_cli_mode_footer, branch on should_use_manual_install_mode() to pick which button to render.

On install failure (handle_install_plugin error callback), set plugin_install_failed = true to switch to manual mode for the rest of the session.

7. Files Changed

• New: workspace/view/plugin_install_modal.rs
• Modified: plugin_manager/mod.rs — PluginInstallStep, PluginInstallInstructions, new trait method
• Modified: plugin_manager/claude.rs — LazyLock implementation
• Modified: cli_agent_sessions/mod.rs — is_remote field on CLIAgentSession, threaded through register_listener
• Modified: agent_input_footer/mod.rs — two-mode chip, failure tracking, remote detection via session.is_remote, new action/event variants
• Modified: terminal/input.rs, terminal/view.rs — event forwarding, is_remote computation at session creation
• Modified: workspace/util.rs, workspace/view.rs, workspace/mod.rs — modal integration