AI Agents · Lesson L03
Hermes Agent TUI vs Desktop App: Which One Should You Use in 2026?
Hermes Agent has two interfaces — a Terminal User Interface (TUI) and a Desktop App. Both run the same agent underneath. Here's how to pick the right surface for the work, and when to run both at once.
Last tested and updated: June 2026
Use both at once. The TUI and the Desktop App are not competitors. They are two windows into the same Hermes back-end, and most power users run both side-by-side. Switching costs you nothing.
After L02 — How to Install Hermes Agent for Beginners, you ran your first sessions in the TUI. Hermes shipped a second surface in June 2026: a native Desktop App. You do not switch — you add it.
The mental model
The TUI and the Desktop App are two surfaces over the same Hermes back-end. Same config. Same profiles. Same skill bundles. Same model. Same memory. Same session state. You can switch mid-task without losing anything.
The differences are entirely in the surface — what each interface is good at showing and asking you to do.
Think of the agent as the kitchen. The TUI is the line cook’s station — fast, knife-ready, every tool within reach. The Desktop App is the head chef’s pass. Same kitchen. Different vantage points.
The TUI is the original Hermes interface. Keyboard-driven. Runs in any terminal. Sends raw text to the model — nothing else. Built for terminal-native developers: live Git branch in the status line, non-blocking input, and thin-client mode for VPS.
The Desktop App is a native Electron + React app that ships with v0.16 “Surface” (June 2026). It adds features the TUI cannot render: a file-browser sidebar, side-by-side previews, drag-and-drop upload, and a one-click model switcher.
One thing you should know up front. The Desktop App costs roughly 2× more tokens per message than the TUI. Every Desktop message includes UI schemas, layout state, and background file-scanning data. The TUI sends just your text. Same model, same answer, more context billed.
You pay your own API bill. Hermes is BYOK (Bring Your Own Key) from L01. A 3am runaway Desktop session can burn real money overnight. The official docs don’t advertise it. The source video does.
Pick your tool
Match the surface to the work. Open the TUI for coding. Open the Desktop App for orchestration and review. The decision rule has three questions:
- Am I writing code, or managing projects? Writing code → TUI. Managing projects → Desktop App.
- Do I need to see state (files, models, status) without typing? Yes → Desktop App.
- Am I doing this from a VPS over SSH? Yes → TUI. The Desktop App can connect to a remote back-end, but the setup is non-trivial; start with the TUI on the VPS first.
Here’s the same rule in table form:
| Workload | TUI | Desktop App | Why |
|---|---|---|---|
| Coding / shipping features and refactors | Best choice | Token-heavy | TUI’s lower overhead saves real money on long sessions |
| Quick question or chat | Fine | Fine | Either works for low volume |
| Reviewing overnight agent activity | Requires CLI commands | Best choice | Desktop App’s project overview is built for this |
| Switching models | Requires hermes model | One click | Visual model picker |
| Drag-and-drop a file | Type the path | Best choice | Desktop UX |
| Human-in-the-loop workflows | Cumbersome | Best choice | Visual feedback is built for this |
A few things to keep in mind:
- MCPs are still rough in the Desktop App as of v0.16. Discoverability and toggling for MCP integrations work better in the TUI today.
- Bugs are usually back-end bugs. If a bug shows up in the Desktop App, check the TUI first to confirm — they share a back-end.
For the deeper comparison once you’ve tried both, see L09 — Hermes Agent vs Claude Code vs Mavis.
Try it
The exercise
You need two interfaces open at once for this one. If you haven’t installed the Desktop App yet, get it from the same place you got the TUI in L02.
- Open the TUI. Start a session: ask Hermes to summarise a file you have locally — anything, a notes file, a config file, a README.
- Open the Desktop App. Connect to the same Hermes instance. Open the same session.
- Send one message from the TUI. Note the token count or rough cost.
- Send the same message from the Desktop App. Note the token count or rough cost.
- Spend 30 minutes using both. Try the file browser sidebar and the model switcher in the Desktop App. Try the Git branch status line and rapid-fire commands in the TUI.
- Switch back and forth. Notice that state — current conversation, memory, profile — follows you.
A good outcome is one sentence in your own words answering all three of these without re-reading the lesson:
For (a) refactoring a 200-line function, (b) reviewing what three different agents did overnight, and (c) running an MCP-heavy workflow — which interface do I open first, and why?
Watch the full breakdown
If you’d rather hear the morning-meeting framing from Ron directly, here’s the 9-minute source clip:
Check your understanding
The questions live in quiz.json — six standalone questions that Quiz.tsx renders on the live site.
What’s next
- Want to teach Hermes to do specific things? → L04 — Hermes Agent Skills and Skill Bundles Explained.
- Still wondering whether to use Hermes at all? → L09 — Hermes Agent vs Claude Code vs Mavis is the deeper comparison once you’ve tried the basics.