Herdr
agent multiplexer that lives in your terminal.
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What is Herdr?
Herdr is a terminal-native agent runtime and multiplexer that runs inside your existing terminal emulator. It provides persistent PTY sessions with tmux-style detach/reattach capability, mouse-native panes, and semantic agent state awareness (blocked, working, done, idle). Herdr sits between desktop agent terminals and tmux, offering real terminal panes with clickable layouts, workspace/tab/pane organization, remote SSH attach, and a CLI/socket API that agents can drive themselves.
Key features include persistent sessions that survive disconnects, local or remote execution (local machine, SSH sessions, or thin client remote attach), mouse-native TUI with clickable panes/tabs/workspaces, agent state rollups in the sidebar showing which agents need attention, automatic detection of 15+ coding agents (Claude Code, Codex, Copilot, Pi, Cursor, Kimi, Grok, and more), Git worktree support, configurable keybindings, multiple themes (Catppuccin, Tokyo Night, Dracula, Nord, Gruvbox, and 12+ others), and a socket API for automation.
Herdr is designed for developers and power users who run multiple AI coding assistants simultaneously and need a unified interface to manage parallel execution, monitor status, and facilitate inter-agent communication. It targets engineers who want to keep their shell, SSH setup, fonts, and keybinds while adding agent-aware persistence without replacing their trusted terminal emulator.
The tool integrates with JetBrains, Docker, Vercel, Google, NVIDIA, AWS, and many other companies' engineering teams. It supports both keyboard-first workflows and mouse interaction, works on mobile terminals over SSH, and requires only a single Rust binary with no Electron dependency.
Herdr pricing
Pricing model: Freemium
Free and open source under AGPL-3.0 license. No paid tiers, subscription plans, or account required. Single Rust binary installation via curl script, Homebrew core, Nix flake, or direct download. No Electron, no hosted control plane, no web view required.
Herdr pros
- Runs inside your existing terminal emulator (Ghostty, Kitty, iTerm, Alacritty)
- Persistent PTY sessions survive disconnects and detach
- tmux-style detach/reattach without losing agent processes
- Remote SSH attach works like tmux on remote servers
- Mouse-native TUI with clickable panes, tabs, and workspaces
- Semantic agent state awareness (blocked, working, done, idle)
- Automatic detection of 15+ coding agents out of the box
- Agent state rollups in sidebar show which agent needs attention
- CLI and socket API for agent orchestration and automation
- Single Rust binary with no Electron dependency
- Works locally, over SSH, or as thin client to remote host
- Mobile-first responsive TUI for phone/tablet SSH sessions
- Git worktree support creates checkouts as grouped workspaces
- 17+ built-in themes including Catppuccin and Tokyo Night
- Custom command keybindings with environment variable access
- Sound and terminal notification support for agent completion
- Agent session restore resumes Claude Code, Codex, Pi conversations
- Copy mode with vim-like navigation (h/j/k/l, v, y)
- Ctrl-click opens OSC 8 hyperlinks and visible URLs
Herdr cons
- Only supports Linux and macOS (no Windows)
- Requires prefix key (ctrl+b) for most commands like tmux
- Pane screen history disabled by default due to secrets concern
- Sound notifications require external player (paplay, mpv, afplay)
- Kitty graphics support is experimental only
- Nested launches blocked by default (testing only)
- Some agents detected but less thoroughly tested (Gemini CLI, Cline)
- Kiro CLI lacks blocked status detection
- Named sessions require manual management for isolation
Frequently asked questions about Herdr
What is Herdr?
Herdr is a terminal-native agent runtime and multiplexer that runs inside your existing terminal. It provides persistent PTY sessions with tmux-style detach/reattach, mouse-native panes, semantic agent state awareness (blocked, working, done, idle), and a CLI/socket API that agents can drive. It sits between desktop agent terminals (which give app UI) and tmux (which gives persistence), offering real terminal panes with clickable layouts and agent orchestration.
How do I install Herdr?
Install with the curl script: curl -fsSL https://herdr.dev/install.sh | sh. Herdr is also available via Homebrew core, Nix flake, or as a single Rust binary download. Requires Linux or macOS. No Electron, no account, no hosted control plane needed.
Which coding agents does Herdr support?
Automatic detection works for 15+ agents: Pi, Claude Code, Codex, Droid, Amp, OpenCode, Grok CLI, Hermes Agent, Cursor Agent, Antigravity CLI, Kimi Code CLI, Kiro CLI, GitHub Copilot CLI, Qoder CLI, plus less-tested Gemini CLI and Cline. Any terminal agent runs normally as a terminal process, but may not get rich state without an integration.
How does Herdr differ from tmux?
Herdr adds agent awareness to tmux-style persistence. Both run inside your terminal and provide persistent PTY sessions with remote SSH attach. Herdr adds semantic agent state (blocked/working/done/idle), state rollups in the sidebar, mouse-native panes with clickable layout, direct agent attach, and an API agents can orchestrate. tmux is scriptable but lacks agent state awareness.
Can I use Herdr over SSH?
Yes. Run Herdr locally, inside any SSH session on a remote box (session stays on server after detach), or use herdr --remote to point your local client at an SSH config host and stream the remote TUI back to your terminal. The responsive TUI stays usable on mobile terminals from phone or tablet.
How do I detach and reattach to a Herdr session?
Press prefix+q (ctrl+b then q) to detach the client. Agents keep running in the background session server. Run herdr again in your terminal to reattach to the same default session. You do not manage sockets manually. For named sessions, use herdr with the session name.
What keybindings does Herdr use?
Herdr uses prefix mode with ctrl+b as default prefix. Common actions: prefix+v splits right, prefix+minus splits down, prefix+c creates new tab, prefix+n/p navigates tabs, prefix+w for workspace navigation, prefix+shift+n creates new workspace, prefix+q detaches. After detaching, run herdr again to reattach. Custom keybindings are configurable in config.toml.
Does Herdr replace my terminal emulator?
No. Herdr is not a terminal emulator. Use Ghostty, Kitty, iTerm, Alacritty, or any terminal you already trust. Herdr runs real processes in PTYs inside your existing terminal, then adds layout, click targets, state, persistence, and automation around them. It keeps your shell, SSH setup, fonts, and keybinds.
Is Herdr free?
Yes, Herdr is free and open source under AGPL-3.0 license. There are no paid tiers, subscription plans, or required accounts. Installation is via single Rust binary with no Electron dependency, no hosted control plane, and no web view required.