Herdr Gave Me One Terminal for the Whole Herd — and I'm Not Going Back to tmux

Published June 29, 2026 — this is a first-look analysis of Herdr, which hit the front page of Hacker News earlier today.

The Problem No One Solved Until Now

Here's the workflow that broke my tmux setup for good: three Claude Code agents, one OpenCode instance, and a Grok CLI running across two repos, a staging server, and an incident log. Some waiting on human approval. One sitting idle after finishing a refactor. Another deep in a test loop I didn't want to interrupt.

tmux kept them alive — that part worked fine. But I couldn't tell which agent was blocked, which was done, and which had been waiting on me for an hour without scrolling through every pane. The terminal multiplexer I'd used for a decade was built for terminals, not agents. And the gap between "keeps processes alive" and "understands what those processes are doing" is exactly where developer productivity goes to die.

Herdr is what happens when someone builds a multiplexer that actually knows what an AI agent is.

What Herdr Actually Is

Herdr is a single Rust binary — no Electron, no web dashboard, no account required — that lives in your existing terminal. It gives you:

• Persistent panes, tabs, and workspaces — same model as tmux, detach and reattach, processes keep running
• Real-time agent state awareness — a sidebar shows every agent's status as blocked, working, done, or idle at a glance
• A socket API — agents can programmatically split panes, spawn helpers, wait for siblings, and read output

The creator, arzamar (ogulcancelik/herdr), put it simply on Reddit: "I love my terminal and don't wanna leave."

That's the whole ethos. Herdr doesn't try to replace your terminal emulator (keep Ghostty, Kitty, iTerm, whatever). It doesn't move your workflow into a web dashboard or a proprietary app. It sits inside the environment you already work in and makes it agent-aware.

The 30-Second Onboarding

curl -fsSL https://herdr.dev/install.sh | sh
herdr

That's it. Ctrl+B Q detaches — the server keeps running. Run herdr again to reattach. It works over SSH, on a remote box, from a phone client. The TUI is responsive down to mobile width — narrow screens get a switcher built for touch-sized decisions.

Mouse support is baked in from day one. Click panes, drag borders, split and switch from right-click menus. You don't need to memorize keybindings to be productive.

Where Herdr Wins

The comparison matrix on herdr.dev/compare tells the story better than I can:

The difference is in the middle columns. tmux keeps your panes alive but doesn't know what's in them. GUI managers (Solo, Conductor, Emdash, Superset) know about agents but make you leave the terminal and work through their abstraction. Herdr hits the intersection: persistent terminal runtime, built for agents.

The Socket API Changes Things

The most interesting part of Herdr isn't the TUI. It's the local Unix socket API that lets agents control the multiplexer programmatically:

# an orchestration agent can:
herdr workspace create --cwd ~/project --label api
herdr tab create --label logs
herdr pane split 1-1 --direction right
herdr pane run 1-2 "just test"
herdr wait agent-status 1-1 --status done
herdr pane read 1-2 --source recent-unwrapped

This is a genuinely different model from anything else out there. Instead of forcing every agent workflow into a single giant prompt context, you get real process isolation between agents — each runs in its own PTY, with its own working directory, and they can signal each other through the multiplexer.

The Akmatori blog put the distinction well: "The risk is not only losing sessions. The bigger risk is losing state." Herdr treats agent state as a first-class operational concern, not an afterthought.

Which Agents Does It Support?

Out of the box, Herdr detects agent state from the foreground process name and terminal output. The sidebar automatically shows blocked/working/done/idle for:

• Claude Code — full state detection (blocked, working, done)
• Codex — full state detection
• OpenCode — semantic state reporting
• Grok CLI — full state detection
• Cursor Agent, Devin CLI, Droid, Kimi Code CLI, QoderCLI, Kilo Code CLI, Hermes Agent — all supported
• Pi — working, idle/done (blocked partial)

Some agents report state natively (Pi, OMP, Kimi Code CLI, OpenCode, Kilo Code CLI, Hermes). Others provide session identity for restore after a server restart. Herdr falls back gracefully — agents outside the built-in list still work as regular terminal panes.

Yes, it supports Hermes Agent. That's worth noting for anyone running autonomous agent workflows.

The Ecosystem Is Already Growing

Herdr is young — v0.1.x, 929 commits, launched this year — but the community around it is moving fast:

• HerdrPlus — open-source add-on for project templates, session restores, and quick actions
• AgentChute — intra-agent communication protocol built as a Herdr extension, wiring Claude Code, Codex, Gemini, and Grok into shared state
• Telegram Notify plugin — get a message when an agent finishes
• Dev Layout Bootstrap plugin — three-pane dev environment around the current context
• Marketplace — plugin surface based on the CLI + socket API

There's also thurbox, a similar concept that uses tmux as backend for stability — suggesting Herdr's model resonates even with people who want the underlying reliability of an established multiplexer.

The Catch (There's Always a Catch)

Herdr is v0.1.x software. It's being built at speed (929 commits from a small team), which means:

• Windows support is preview/beta only — Linux and macOS are the primary targets
• Some agent integrations are untested — Gemini CLI, Cline are detected but not verified
• No sandboxing — Herdr is a multiplexer, not a security boundary. Agents in different panes share filesystem access
• You're betting on something young — as coles.codes noted, "It does what it claims, but you're betting on something young, so I've kept my tmux config around as a fallback"

The creator is transparent about these limitations. The agent guide lets you paste a prompt into your agent to have it walk you through setup, which is a smart onboarding move for the target audience.

What This Means

The terminal multiplexer is one of those tools that ossified a decade ago. tmux is still actively maintained but hasn't fundamentally reimagined its model since its early years. Zellij brought modern UX but didn't fundamentally reimagine the model either. The assumption was that a multiplexer's job stops at keeping processes alive.

Herdr challenges that assumption by observing that AI agents are a new kind of process with a lifecycle that matters: blocked vs working vs done vs idle. A multiplexer that doesn't surface that state is leaving a massive productivity gain on the table.

Will Herdr replace tmux for everyone? No. If you run one agent in one terminal, you don't need it. But if you're running multiple agents across projects, reaching for more sophisticated orchestration, or SSH-ing into remote boxes to manage agent workloads, Herdr fills a gap that didn't exist until recently — because the tools it manages didn't exist until recently either.

Install it, run two agents, split a pane, then detach once. The value shows up the first time the herd keeps running after your terminal disappears.

Links: GitHub · Website · Docs · Compare