Hermes Cua is Cua's own plugin for Hermes Agent, called cua-spaces, and it runs Hermes's terminal, file and code tools inside a Cua Space instead of on your computer.
A Cua Space is an isolated Linux, macOS or Windows machine that you can watch live, on your own hardware or in your own cloud account.
You set it up with three commands, and after that every command, file write and code run lands in the Space.
Hermes Agent is the free, open-source agent from Nous Research, and the plugin comes from Cua, the open-source computer-use company behind the trycua GitHub projects.
The plugin went into the official Hermes plugin catalog on 20 October 2026 with a "Verified" badge, and it was updated on 21 October.
I covered it in my video below, which walks through the news with Cua's own demo footage.
I haven't run the plugin on my own machine yet, so this walkthrough comes straight from Cua's README, the Hermes catalog page and Nous's docs.
The Hermes Cua Setup At A Glance
This is the whole setup on one screen, and the rest of the page walks through each step in order.
| Step | What you do | The command or setting |
|---|---|---|
| 1 | You install Cua and sign in if you want cloud Spaces. | You run Cua's install script from Step 1, then cua auth login. |
| 2 | You install the cua-spaces plugin and say yes to its prompts. | hermes plugins install https://github.com/trycua/hermes-cua-spaces |
| 3 | You point Hermes's terminal at Cua. | hermes config set terminal.backend cua |
| 4 | You check that commands land in the Space. | You ask Hermes to run hostname and cat /etc/os-release. |
| 5 | You tune where Spaces go and whether they are kept. | You set space, on, image, desktop and delete_on_exit. |
| 6 | You watch the Space live and take over when you need to. | You open the Cua Spaces app, or run cua spaces ls and cua viewer. |
What Hermes Cua Actually Is
Hermes still runs where it runs today, which is usually your own laptop or server.
The difference is where the work happens.
When Hermes needs to run a command, write a file or execute code, the plugin sends that work into a Cua Space instead of your computer.
Cua's README draws it as a simple chain, which I've copied here.
you -> Hermes (your machine) -> this plugin -> Cua Space (an isolated Linux, macOS or Windows machine)
terminal, files, code run here
Technically, the plugin is a terminal backend, which is the same kind of setting as Docker or SSH in Hermes.
If you want the wider picture of every backend Hermes supports, read my Hermes Agent sandbox setup guide first.
The catalog page lists the plugin as version 0.4.0, maintained by trycua, with a minimum Hermes version of 0.21.6 and support for Linux, macOS and Windows.
The plugin itself is MIT licensed, the same licence as the Cua SDKs.
One detail I like is that Cua isn't new to Hermes at all.
Nous's computer-use docs say Hermes's built-in computer_use toolset already drives cua-driver, the open-source background driver from the same trycua project.
Why Throwaway Computers Change How You Run Hermes
Here's the old way most people run an agent.
The agent sits on your real machine, and you approve every risky command because one bad rm could hit your actual files.
That means you can't really walk away, because the agent keeps stopping to ask you something.
The new way is a throwaway computer for every run.
With the default settings, each Hermes run makes its own Space, names it hermes-<task>-<random>, does the work there and deletes it when it finishes.
Because that Space is a disposable sandbox, Hermes skips its risky-command prompts for Spaces the plugin creates, the same way it does for its other container backends.
In my video I described it as a virtual employee you sit next to, because you can watch the screen and step in whenever you want.
Step 1: Install Cua And Sign In
First, install the Cua command-line tool with Cua's install script.
curl -fsSL https://cua.ai/install.sh | sh
cua auth login
The README is clear that sign-in is only needed for Spaces on your cua.ai account.
If you only want a local Space on your own machine, you can skip cua auth login.
The plugin never stores a token or key, because it talks to Cua through the cua Python package, which uses the sign-in that cua auth login saved.
Step 2: Install The cua-spaces Plugin
Next, install the plugin from Cua's GitHub repository.
hermes plugins install https://github.com/trycua/hermes-cua-spaces
The Hermes catalog page also shows a short form of the same install.
hermes plugins install cua-spaces
Hermes asks to install one Python package, which is cua.
The README says to answer yes to that, and yes again to enabling the plugin.
Step 3: Point Hermes At Cua
Now switch Hermes's terminal backend to Cua with one command.
hermes config set terminal.backend cua
The first command creates a Space, and the README warns that the first one takes a few minutes while Cua downloads the machine image.
After that, every terminal command, file read, file write and code run lands in the Space.
Step 4: Check It Worked
The README gives you a simple test prompt to type into Hermes.
run hostname and cat /etc/os-release
You should see the Space's name and Ubuntu, not your own computer.
On a Windows Space, the README says to ask for hostname and (Get-CimInstance Win32_OperatingSystem).Caption instead.
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Step 5: Tune The Hermes Cua Settings
The plugin keeps its settings in Hermes's config.yaml under plugins.entries.cua-spaces.settings, and you set them with hermes config set.
| Setting | Default | What it does |
|---|---|---|
space |
create |
It makes a Space for you, or you give it the name or id of a Space you already have. |
on |
Your Cua default | It decides where a new Space goes, which can be local, cloud, host:<machine> or one of your machine names. |
image |
linux |
It picks the image, where linux is Ubuntu with a desktop and windows makes a Windows Space. |
desktop |
false |
It installs what Bot Desktop, computer_use and the browser need into a Linux Space that lacks it. |
delete_on_exit |
true |
It deletes a Space the plugin created when Hermes finishes, and a Space you named is never deleted. |
create_timeout |
600 |
It sets how many seconds to wait for a new Space to be ready. |
These are the two examples the README gives.
# use a Space you already made
hermes config set plugins.entries.cua-spaces.settings.space my-box
# make new Spaces on another of your machines
hermes config set plugins.entries.cua-spaces.settings.on "spare mac mini"
The environment variables HERMES_CUA_SPACE, HERMES_CUA_ON, HERMES_CUA_IMAGE and HERMES_CUA_DESKTOP override the same settings for one shell.
The three ways the plugin picks a Space
This is the part that decides how your setup behaves day to day.
- With
space: create, which is the default, every Hermes run gets its own fresh Space that is deleted at the end. - With
space: createanddelete_on_exit: false, the plugin makes one Space calledhermes-defaultand reuses it, so your files are still there next session. - With
space: my-box, the plugin uses that Space and never deletes or stops it, and Hermes keeps asking before risky commands.
If you keep hermes-default running, the README says you can stop it with cua spaces stop hermes-default or delete it with cua spaces delete hermes-default.
Step 6: Watch The Space Live And Take Over
Open the Cua Spaces app and click the Space, and you'll see its desktop as Hermes works.
In a terminal, cua spaces ls lists your Spaces and cua viewer serves a browser viewer for all of them.
You can click in the viewer to take over, and Hermes keeps working next to you.
Cua's own Spaces page says you and every agent get a cursor of your own on the same desktop, and that your team can work side by side in a shared Space.
Run Two Hermes Agents Side By Side
Every Hermes run gets its own Space by default, so two runs at once never touch each other's files.
If you want named Spaces per profile, the README shows this pattern.
HERMES_CUA_SPACE=build-a hermes --profile a
HERMES_CUA_SPACE=build-b hermes --profile b
Both Spaces must exist first, and you create them with cua spaces create linux --name build-a.
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Turn On Computer Use Inside The Space
The catalog page says that on Hermes 0.22.3 and later, Bot Desktop, computer_use and the browser follow the terminal into the Space.
The README lists three conditions for that to work.
- You need a Linux Space, because macOS and Windows Spaces keep these tools on your own machine.
- You need the
cuacommand on your PATH at version 0.7.0 or newer. - You need the desktop stack inside the Space, which the plugin can install for you.
This one command tells the plugin to install the desktop stack on the next run.
hermes config set plugins.entries.cua-spaces.settings.desktop true
The README says the install takes a few minutes, needs internet and sudo in the Space, and does nothing if the stack is already there.
If the cua command is missing or too old, Hermes says the screen cannot follow the terminal, and you can set bot_desktop.placement: gateway to run it on your machine instead.
I've written a separate guide on the Hermes computer use skill, which explains the computer_use tool itself and how to turn it on.
What Runs In The Space And What Doesn't
| Hermes tool | Does it run in the Space? |
|---|---|
The terminal tool and background processes |
Yes, they run in the Space. |
| The file tools for read, write, patch and search | Yes, they run in the Space. |
execute_code |
Yes, it runs in the Space. |
Bot Desktop, computer_use and the browser tools |
They run in Linux Spaces on a new enough Hermes with the desktop stack, but not in macOS or Windows Spaces. |
| The same tools on an older Hermes | No, they use your own machine as before. |
Windows Spaces In Brief
You can make a Windows Space with cua spaces create windows --name my-pc and point the plugin at it.
The README warns that a Windows Space on an Apple silicon Mac runs by emulation and is slow, so it suggests an x86 machine or your cloud account for real work.
The terminal there runs in PowerShell, and the plugin installs Git for Windows the first time if the Space lacks it.
Two Other Ways To Use Cua With Hermes
The README lists two routes that need no plugin at all.
The first is giving Hermes the Cua tools through cua mcp, so Hermes can create Spaces, run commands in them, drive their desktops and delete them itself.
mcp_servers:
cua:
command: cua
args: ["mcp"]
You can limit it with --permissions, for example args: ["mcp", "--permissions", "spaces:readonly"], and with tools.include in the same block.
If MCP is new to you, my Hermes Agent MCP server guide explains how Hermes loads these servers.
The second route runs Hermes itself inside a Space, so the agent, its keys and its tools all stay there.
cua agent create ada --harness hermes --in local:dev --env-from-host OPENAI_API_KEY
cua agent tell ada "summarize the repo in /home/cua/project"
The README says Hermes keeps its memory in your Cua Volume in that setup, so it survives if the Space is replaced.
Common Hermes Cua Problems And Fixes
The plugin explains its errors in plain words, and these are the fixes the README lists.
| You see | Do this |
|---|---|
| "Cua did not accept your sign-in" | You run cua auth login again. |
| "Cua can't find the Space ..." | You run cua spaces ls, then fix the space setting or use create. |
| "Cua can't start a Space here yet" | You run cua doctor to see what is missing. |
"The cua Python package is not installed" |
You run hermes pm repair. |
| A Windows Space has no Git for Windows | You run winget install --id Git.Git -e in the Space's PowerShell and start Hermes again. |
What The Plugin Sends And What It Doesn't
With a local Space, the README says nothing leaves your machine.
With a Space on another machine or your cloud account, commands and files go through Cua's encrypted relay or your own network.
The plugin does not sync your Hermes skills, cache or credentials into the Space, so the Space starts with only what its image has.
The plugin adds no telemetry, but the cua package has its own anonymous usage telemetry, which you turn off with cua telemetry off or CUA_TELEMETRY=0.
Who Is Behind Cua
Cua's Y Combinator page lists it in the Spring 2025 batch, based in San Francisco, with Francesco Bonacci as founder and CTO.
Its original YC launch post says its Lume virtual machines run at up to 97% of native CPU speed on Apple Silicon.
The main trycua/cua repository is MIT licensed and had about 30,700 stars and 2,200 forks on GitHub when I checked on 23 October 2026.
Cua's README also mentions a limited launch offer on Spaces Pro and Teams for Hermes users, open to the first 50 people until 15 November, and the details are on the plugin's GitHub page.
Tips I'd Follow Before Trusting It With Client Work
These are my own operator rules, built on what the docs say.
- Keep the default throwaway mode for anything risky, so a bad command dies with the Space.
- Read the list of the best Hermes Agent tools to see what else is worth adding around it.
If you want help working out where an agent like this fits your SEO business, you can book a free SEO strategy session with my team.
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Related Reading
- The Hermes Agent sandbox setup, backend by backend
- The Hermes computer use skill, explained and switched on
- The Hermes Agent MCP server, both directions
- The best Hermes Agent tools right now
Also On Our Network
- 🌐 Seven ways a business uses Hermes Cua throwaway computers
- 🌐 The Hermes Cua plugin, feature by feature with scores
- 🌐 The Hermes Cua quick start for your Agent OS
- 🌐 Which models to run inside a Cua Space, measured on GoldieBench
FAQ: Hermes Cua
What is Hermes Cua?
It's Cua's own cua-spaces plugin for Hermes Agent, which runs Hermes's terminal, file and code tools inside a Cua Space.
A Space is an isolated Linux, macOS or Windows machine that you can watch live.
How do I install the Hermes Cua plugin?
Install Cua with its install script, sign in if you want cloud Spaces, run hermes plugins install https://github.com/trycua/hermes-cua-spaces, then run hermes config set terminal.backend cua.
Do I need a Cua account to use Hermes Cua?
No, the README says a local Space needs no sign-in.
You only need cua auth login for Spaces on your cua.ai account.
Does Hermes still ask for approval inside a Cua Space?
Hermes skips its risky-command prompts for Spaces the plugin creates, because those Spaces are disposable.
It keeps asking in a Space you named, because that one is your machine.
Can computer use run inside the Cua Space?
Yes, in Linux Spaces on Hermes 0.22.3 or later, with the cua command on your PATH and the desktop stack installed.
macOS and Windows Spaces keep computer use on your own machine.
If you run an agency and want help mapping agents to your client work, you can book a free strategy session and we'll talk it through.
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About Julian
I'm Julian Goldie, an SEO entrepreneur, author and founder of the AI Profit Boardroom, which has 3,400+ members.
I help business owners scale with AI agents, automation and SEO.
- I've built a 7-figure SEO and link-building agency, Goldie Agency, with 70+ people in Bangkok.
- I've grown a YouTube channel to 400,000+ subscribers.
- I wrote the book "Link Building Mastery", which covers nine link building strategies.
- I run GoldieBench, where I score AI models on real one-shot builds.
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Install Cua, add the plugin, switch the backend with one command, and every run gets its own throwaway computer with Hermes Cua.
