liminal-ai

Liminal Builder

Name: Liminal Builder
Author: liminal-ai

AI community

SOURCE https://github.com/liminal-ai/liminal-builder

Description

Agentic IDE wrapping AI coding CLIs with organized session management

Installation

This entry records only its repository, not the path inside it, so there is no exact command to give. Open the source below and copy the folder into ~/.claude/skills/, or the file into ~/.claude/agents/.

README

Liminal Builder

An agentic IDE that replaces the friction of juggling CLI terminals with an organized, session-based interface for parallel AI-assisted development. Move between projects and agent conversations fluidly — no more lost terminal windows, no more "which tab was that Codex session in?"

What It Does

Liminal Builder wraps AI coding CLIs (Claude Code, Codex) via the [Agent Control Protocol (ACP)](https://github.com/anthropics/claude-code/tree/main/packages/agent-control-protocol) and provides:

Project sidebar — Add project directories, browse agent sessions grouped by project, collapse/expand folders
Chat interface — Send messages, stream responses, see tool calls and thinking blocks inline with status indicators
Tab management — Multiple sessions open simultaneously, instant switching (content stays alive in background iframes), drag-to-reorder
Multi-CLI support — Claude Code and Codex sessions side by side, same interface
Session persistence — Sessions survive app restart; conversation history loads from ACP agents on demand

Architecture

flowchart LR
    subgraph Browser["Browser (vanilla HTML/JS)"]
        Shell["Shell (single page)"]
        Sidebar
        Tabs["Tab Bar"]
        Portlets["Portlet iframes\n(one per session)"]
        Shell --- Sidebar
        Shell --- Tabs
        Shell --- Portlets
    end

    subgraph Server["Bun + Fastify Server"]
        WS["WebSocket Bridge"]
        PS["ProjectStore"]
        SM["SessionManager"]
        AM["AgentManager"]
        ACP["AcpClient"]
        WS --- PS
        WS --- SM
        WS --- AM
        AM --- ACP
    end

    subgraph Agents["ACP Agent Processes"]
        CC["claude-code-acp"]
        CX["codex-acp"]
    end

    Shell <-->|WebSocket| WS
    ACP <-->|JSON-RPC/stdio| CC
    ACP <-->|JSON-RPC/stdio| CX

**Shell/portlet model:** The shell manages the sidebar, tab bar, and a single WebSocket connection. Each open session is an iframe