Agent Flow

Real-time visualization of Claude Code, Codex, and Pi agent orchestration. Watch your agents think, branch, and coordinate as they work. Demo video here.

Why Agent Flow?

I built Agent Flow while developing CraftMyGame, a game creation platform driven by AI agents. Debugging agent behavior was painful, so we made it visual. Now we're sharing it.

Claude Code is powerful, but its execution is a black box — you see the final result, not the journey. Agent Flow makes the invisible visible:

• Understand agent behavior — See how Claude breaks down problems, which tools it reaches for, and how subagents coordinate
• Debug tool call chains — When something goes wrong, trace the exact sequence of decisions and tool calls that led there
• See where time is spent — Identify slow tool calls, unnecessary branching, or redundant work at a glance
• Learn by watching — Build intuition for how to write better prompts by observing how Claude interprets and executes them

Features

• Live agent visualization: Watch agent execution as an interactive node graph with real-time tool calls, branching, and return flows
• Claude Code + Codex + Pi: Auto-detects sessions from all three runtimes and shows them side-by-side, or restricts the watcher to one runtime
• Claude Code hooks: Lightweight HTTP hook server receives events directly from Claude Code for zero-latency streaming
• Codex rollout tailing: Reads ~/.codex/sessions/**/rollout-*.jsonl (respects CODEX_HOME) and surfaces tool calls, reasoning, and authoritative token counts from Codex's own event stream
• Pi session tailing: Reads Pi session JSONL, preserves recorded activity times, and shows persisted pi-subagents children
• Multi-session support: Track multiple concurrent agent sessions with tabs
• Interactive canvas: Pan, zoom, click agents and tool calls to inspect details
• Timeline & transcript panels: Review the full execution timeline, file attention heatmap, and message transcript
• JSONL log file support: Point at any JSONL event log to replay or watch agent activity

Getting Started

Quick Start (no VS Code required)

npx agent-flow-app

This starts the visualizer in your browser. Start a supported agent session in another terminal to stream its events.

Options:

• --port <number> — change the server port (default: 3001)
• --pi-session-dir <path> — override the Pi session directory
• --no-open — don't open the browser automatically
• --verbose — show detailed event logs

Standalone Web App (from source)

git clone https://github.com/patoles/agent-flow.git
cd agent-flow
pnpm i
pnpm run setup      # configure Claude Code hooks (one-time)
pnpm run dev        # start the web app + event relay

Open http://localhost:3000 and start a supported agent session in another terminal.

VS Code Extension

1. Install the extension
2. Open the Command Palette (Cmd+Shift+P) and run Agent Flow: Open Agent Flow
3. Start a Claude Code, Codex, or Pi session in your workspace — Agent Flow will auto-detect it

Agent Flow automatically configures Claude Code hooks the first time you open the panel. To manually reconfigure, run Agent Flow: Configure Claude Code Hooks from the Command Palette.

Runtime selection

By default Agent Flow watches Claude Code (~/.claude/projects/), Codex (~/.codex/sessions/), and Pi (~/.pi/agent/sessions/) in all three entry points. Sessions appear side-by-side and use runtime-specific labels.

To restrict to one runtime:

• VS Code extension: set agentVisualizer.runtime to "auto", "claude", "codex", or "pi"
• pnpm run dev and npx agent-flow-app: set AGENT_FLOW_RUNTIME to claude, codex, or pi

For non-default Codex installs, set CODEX_HOME.

For Pi, Agent Flow follows PI_CODING_AGENT_SESSION_DIR, project and global sessionDir settings, PI_CODING_AGENT_DIR, then ~/.pi/agent. The VS Code agentVisualizer.piSessionDir setting, standalone --pi-session-dir option, or AGENT_FLOW_PI_SESSION_DIR variable overrides that discovery. Agent Flow can expand only subagents that persist their own session files.

JSONL Event Log

You can also point Agent Flow at a JSONL event log file:

1. Set agentVisualizer.eventLogPath in your VS Code settings to the path of a .jsonl file
2. Agent Flow will tail the file and visualize events as they arrive

Commands

Command	Description
Agent Flow: Open Agent Flow	Open the visualizer panel
Agent Flow: Open Agent Flow to Side	Open in a side editor column
Agent Flow: Connect to Running Agent	Manually connect to an agent session
Agent Flow: Configure Claude Code Hooks	Set up Claude Code hooks for live streaming

Keyboard Shortcut

Shortcut	Action
Cmd+Alt+A (Mac) / Ctrl+Alt+A (Win/Linux)	Open Agent Flow
Cmd+K (Mac) / Ctrl+K (Win/Linux)	Search and switch sessions when more than one session is available

Settings

Setting	Default	Description
agentVisualizer.runtime	"auto"	Which agent runtime(s) to watch: "auto" (all), "claude", "codex", or "pi"
agentVisualizer.piSessionDir	""	Optional Pi session directory override
agentVisualizer.devServerPort	0	Development server port (0 = production mode)
agentVisualizer.eventLogPath	""	Path to a JSONL event log file to watch
agentVisualizer.autoOpen	false	Auto-open when an agent session starts

Requirements

• Node.js 20+ (LTS recommended)
• pnpm
• A supported agent CLI: Claude Code, Codex, or Pi
• For the VS Code extension: a VSCode-compatible IDE 1.85+ (e.g. VS Code, Cursor, Windsurf)

Development

pnpm i              # install dependencies for all packages
pnpm run setup      # configure Claude Code hooks (one-time)
pnpm run dev        # start dev server + event relay

pnpm run dev starts the Next.js server and an event relay for Claude Code, Codex, and Pi sessions.

Other scripts:

Script	Description
pnpm run dev:demo	Start with demo/mock data
pnpm run dev:relay	Run the event relay server standalone
pnpm run dev:extension	Watch-build the extension
pnpm run build:all	Production build (webview + extension)
pnpm run build:web	Build the Next.js web app
pnpm run build:extension	Build the extension
pnpm run build:webview	Build the webview assets

Star History

Author

Created by Simon Patole, for CraftMyGame.

Privacy & Telemetry

Agent Flow ships opt-out anonymous usage telemetry, enabled by default only in the published npx agent-flow-app binary. pnpm run dev and the VS Code extension emit nothing. Only aggregate events are sent — session count, duration, event count, OS/arch, Agent Flow version, distinct model IDs observed, which runtimes were watched, and error class names. Prompts, file paths, tool calls, user info, and environment variables are never sent.

• Turn off: export AGENT_FLOW_TELEMETRY=false or export DO_NOT_TRACK=1 (disabled installs write zero state to disk — no ~/.agent-flow/ directory)
• Inspect the payload: cat ~/.agent-flow/telemetry/events.jsonl
• Full schema + exact fields: see the v0.8.1 entry in extension/CHANGELOG.md or the serialize() function in scripts/telemetry.ts
• Reset your anonymous identity: delete ~/.agent-flow/installation-id — a fresh random UUIDv4 will be generated on next run

License

Apache 2.0 — see LICENSE for details.

The name "Agent Flow" and associated logos are trademarks of Simon Patole. See TRADEMARK.md for usage guidelines.