Fury IDE

A prototype IDE for AI-assisted development built with Next.js and Claude Code. Fury IDE provides a web-based interface for interacting with the Claude CLI, managing chat sessions, building visual workflows, and organizing project notes.

Features

Chat Interface

• Claude CLI sessions - Sessions are native Claude CLI sessions using --session-id and --resume, with full conversation context managed by the CLI
• Unified session list - Browse all sessions from ~/.claude/history.jsonl with live session indicators
• Streaming responses - Real-time streamed output from Claude CLI with tool use activity indicators
• Markdown rendering - Assistant responses rendered with syntax highlighting (via react-markdown, remark-gfm, rehype-highlight)
• Rich text input - TipTap-based editor with code block support (Enter to send, Shift+Enter for newline)
• Stop/Kill controls - Abort in-flight requests or kill stuck Claude CLI processes
• AskUserQuestion support - Interactive dialog when Claude requests user input via the AskUserQuestion tool
• Prompt suggestions - Detects stale/idle sessions with incomplete responses and suggests follow-up prompts (configurable)
• Long conversation warnings - Visual indicator when sessions exceed 50 messages
• Compaction detection - Hides context compaction messages from the transcript with visual indicator

Canvas (Workflow Builder)

• Drawflow-based visual canvas - Drag-and-drop node editor for building workflows
• Node types - Rectangle, Diamond, and Circle nodes with configurable inputs/outputs
• Per-node chat - Double-click any node to open a chat session scoped to that node
• Workflow persistence - Create, rename, delete, and auto-save workflows to disk
• Import/Export - Workflows stored as JSON in .claude-workflows/

Right Panel

• Stream - Live stream of tool use events, text output, and errors during Claude responses
• File Tree - Explore the active session's project directory (filters out node_modules, .next, .git, etc.)
• Notes - Per-project rich text notes with auto-save (stored in ~/.claude-session-notes/)
• MCP Servers - Manage Model Context Protocol servers with a guided wizard

Settings

• Allow external connections - Toggle to permit or block access from non-localhost IPs
• Prompt suggestions - Toggle to enable/disable follow-up prompt suggestions for stale sessions

General

• Light/Dark theme - Toggle via toolbar button, persisted in localStorage
• Directory picker - Browse filesystem to select project directories for new sessions
• Resizable panels - All panels are drag-resizable via react-resizable-panels
• UI state persistence - Active tab and workflow selection restored across page reloads

Tech Stack

• Framework: Next.js 16 (App Router, Turbopack)
• Language: TypeScript
• Styling: Tailwind CSS 4, shadcn/ui components (Radix UI primitives)
• Editor: TipTap (rich text input + notes)
• Canvas: Drawflow
• AI: Claude CLI (claude command) spawned as child processes via SessionManager
• Code Search: codemogger (local semantic + keyword search via MCP)
• Fonts: Geist Sans / Geist Mono

Data Storage

Data	Location
Session transcripts	~/.claude/projects/<slug>/<sessionId>.jsonl (Claude CLI managed)
Chat history	~/.claude/history.jsonl (Claude CLI global, also appended by Fury)
Transcript archive	~/.claude/fury.db (SQLite, Fury managed)
Workflows	.claude-workflows/*.json (project-local)
UI state	.claude-ui-state/state.json (project-local)
App settings	.claude-ui-state/settings.json (project-local)
Saved prompts	.claude-prompts/*.json (project-local)
Session notes	~/.claude-session-notes/*.md (user home)
MCP servers	~/.claude.json (user scope) or .mcp.json (project scope), created and managed by Claude CLI via claude mcp add/remove
Code search index	~/.codemogger/index.db (codemogger, user home)
Theme	localStorage (browser)

Transcript Database

Claude Code auto-deletes session JSONL files after 30 days (controlled by cleanupPeriodDays in ~/.claude/settings.json). Fury maintains an independent SQLite archive at ~/.claude/fury.db so transcripts survive cleanup.

How it works:

The database is populated automatically through four triggers:

1. Startup scan — On first connection, scans all ~/.claude/projects/*/ JSONL files and archives any that are new or changed.
2. History watcher — When history.jsonl changes (any session, including external CLI), archives the recently-active sessions.
3. Transcript watcher — When a watched session's JSONL changes during a live session, archives it immediately.
4. Archive-on-read — When /api/transcript loads a JSONL, persists it as a fire-and-forget side effect.

A SHA-256 hash per session ensures duplicate archival is a no-op. When a JSONL file is missing (deleted by cleanup), the transcript API falls back to SQLite transparently. The history list merges archived sessions so cleaned-up sessions remain visible.

Schema (3 tables):

• sessions — session metadata, project path, display text, message count, content hash
• messages — parsed transcript messages (role, content, timestamp, turn index)
• raw_jsonl — original JSONL lines preserved for full-fidelity restoration

Technology: @libsql/client (Turso/libSQL) with WAL mode for concurrent read/write safety.

Manual population:

npx tsx scripts/populate-db.ts           # Archive all existing JSONL files
npx tsx scripts/populate-db.ts --dry-run # Preview without writing
npx tsx scripts/populate-db.ts --verbose # Show per-file details

Session Lifecycle

Fury does not maintain long-running Claude processes. Sessions are stateless on the server between messages:

1. Creating a session — Purely a frontend operation. A UUID is generated and stored in React state. No Claude process is spawned, no server-side state is created. The session only materialises on disk when the first message is sent.

2. Sending a message — A claude --print --session-id <uuid> process is spawned (or --resume <uuid> for subsequent messages). It handles one prompt, streams the response back via SSE, writes to the JSONL transcript file, and exits. There is no persistent process per session.

3. Switching sessions — Purely a frontend operation. The UI swaps which transcript is displayed by loading the target session's JSONL from disk. No processes are spawned or terminated. If a Claude process is mid-response when you switch away, it continues running to completion in the background — its SSE handler simply stops updating the display, and the data is persisted to JSONL for when you return.

4. Conversation continuity — Managed entirely by the Claude CLI via --resume <uuid>. On each message, the CLI re-reads the session's JSONL file to reconstruct conversation context. Fury itself does not track conversation history.

5. Parallel sessions — Multiple sessions can process messages concurrently. Each spawns its own short-lived Claude process with a distinct session UUID. The activeSessionRef mechanism ensures only the currently-viewed session's SSE handler updates the display, preventing cross-session contamination.

Getting Started

Prerequisites

• Node.js 20+
• Claude CLI installed and authenticated (claude command available in PATH)

Install & Run

cd Fury
npm install
npm run dev

Open http://localhost:3879 in your browser.

Scripts

Command	Description
npm run dev	Start dev server with Turbopack on port 3879
npm run build	Production build
npm start	Start production server on port 3879
npm run lint	Run ESLint
npx tsx scripts/populate-db.ts	Populate transcript database from existing JSONL files