Give it a personality

By default, Hermes talks like a polite, helpful, slightly formal assistant. That's fine. It's also boring, and it probably doesn't match how you want to work.

Hermes has two ways to change this. One is permanent, one is for a single session. Both are worth knowing.

Permanent: SOUL.md

SOUL.md is a text file that Hermes reads every time it starts. It lives at ~/.hermes/SOUL.md. Whatever you write in it becomes the first thing in Hermes's system prompt — the baseline personality that sits underneath everything else.

Think of it as a letter you write to your agent about who it should be.

Open the file:

nano ~/.hermes/SOUL.md

If it doesn't exist yet, create it. Start simple:

# Who you are

You are my personal terminal assistant. We've been working together for a long time.

# How you talk

Direct. No preamble. No apologies. If I ask a dumb question, tell me it's a dumb question.
Short sentences. Plain language. Skip the bullet points unless I explicitly ask for a list.

# How you work

When I ask you to fix something, show me the diff before touching the file.
When I ask you to run a command that could break something, describe what it does first.
When you don't know the answer, say so. Don't guess.

# What I like

I like concrete examples more than abstract explanations.
I prefer command-line tools over GUIs.
I'm a fast reader. Don't hold my hand.

Save the file. The next time you start Hermes, that's your personality baseline. You don't need to pass any flags — Hermes picks it up automatically.

Temporary: /personality

Sometimes you want a different vibe for one conversation. Maybe you're writing marketing copy and want Hermes to be more creative. Maybe you're teaching someone and want Hermes to explain things patiently.

Inside a chat:

/personality concise

Or:

/personality teacher

These are built-in personalities that overlay on top of your SOUL.md for the current session. When you exit, they're gone — SOUL.md is back in charge.

Built-in personalities include helpful, concise, technical, creative, teacher, catgirl, pirate, shakespeare, and a bunch of others. Type /personality without arguments to see the list.

You can also define your own custom personalities in ~/.hermes/config.yaml under agent.personalities, if you find yourself switching between specific modes often.

Which one to use

SOUL.md is for who Hermes is. /personality is for how Hermes is acting right now.

If you only ever remember one, remember SOUL.md. It's the file that actually shapes your long-term relationship with the agent.

Checkpoint — Edit your SOUL.md, save it, then run hermes and say hi. The reply should feel different from before. Not dramatically different — more like the agent finally knows who it's talking to.

A few things that work well in SOUL.md

Based on what works for people who use Hermes daily:

• Be specific about tone. "Direct" and "no apologies" are better than "friendly."
• Say what you don't want. "Don't use bullet points" is more effective than positive instructions.
• Mention your expertise. If you're a senior engineer, say so. Hermes will stop explaining basics.
• Keep it short. A SOUL.md that's too long takes up context room. Aim for something you can read in thirty seconds.

Next: teaching Hermes to remember things between conversations.