Extending Hermes Agent with Custom Skills: A Practical Guide

Hermes Agent ships with a set of built-in capabilities, but its real power comes from skills — reusable packages that encapsulate specialized workflows. A skill turns a procedure you would otherwise describe in every prompt into something the agent loads on its own when the task matches.

What a Skill Contains

Every skill lives in its own directory with a standard structure:

skills/
  security-audit/
    SKILL.md          # Instructions the agent follows
    scripts/
      audit.sh        # Executable automation scripts
    templates/
      report.md       # Output templates
    references/
      patterns.md     # Reference material

The SKILL.md is the heart of the system. It tells the agent when to use the skill, what steps to follow, and what pitfalls to avoid:

---
name: security-audit
description: "Audit a codebase for security vulnerabilities"
---

# Security Audit Skill
1. Scan for hardcoded secrets using scripts/audit.sh
2. Check dependency tree for known CVEs
3. Review auth middleware for common bypass patterns
4. Generate report using templates/report.md

The name and description frontmatter fields do the routing: only the description stays in the agent’s active context, and the full skill body loads when a task matches. That keeps expertise available on demand without paying for it on every turn.

Finding Skills

Hermes pulls skills from skills.sh, well-known agent skill endpoints, GitHub, ClawHub, and other registries. Browse what’s out there before writing your own:

hermes skills search code-review
hermes skills browse

Both commands return skills with their descriptions, so you can judge relevance before touching anything.

Installing Skills

Install by registry identifier or by a direct URL to a SKILL.md:

# from a registry identifier
hermes skills install openai/skills/skill-creator

# from a direct URL to a SKILL.md file
hermes skills install https://example.com/skills/deploy/SKILL.md --name deploy

# install without the confirmation prompt (needed in TUI mode)
hermes skills install code-review --yes

# override which category folder the skill lands in
hermes skills install deploy --category release

The installer scans what it downloads before committing; --force installs despite a blocked scan verdict — only use it when you trust the source. The --name override helps when you install from a URL whose SKILL.md has no name: frontmatter.

Managing Installed Skills

The day-to-day commands:

hermes skills list          # show installed skills
hermes skills inspect        # preview a skill without installing it
hermes skills check          # check installed skills for updates
hermes skills update         # update installed skills
hermes skills audit          # re-scan installed skills against registries
hermes skills uninstall x    # remove an installed skill

That check/update cycle matters. Skills aren’t static — the good ones get fixed and extended upstream. A weekly hermes skills check keeps your whole toolkit current instead of running stale instructions.

Bundled Skill Management

Some skills ship with Hermes itself. Editing one is allowed — Hermes tracks that you modified it and keeps your changes across updates:

hermes skills list-modified    # which bundled skills have you edited
hermes skills diff             # how your copy differs from the stock version
hermes skills reset <skill>    # clear 'user-modified' so updates apply again

reset is the escape hatch: if your edits go stale against a newer stock version, reset clears the modified flag and hermes skills update takes over again. You can also opt out entirely of bundled-skill seeding with hermes skills opt-out (opt back in with opt-in), or backfill missing official optional skills with repair-official.

Configuring Skills

hermes skills config opens an interactive view to enable or disable individual skills. If a skill keeps matching tasks you don’t want it in, disable it there — that’s the designed control surface, cleaner than deleting it.

Snapshots: Move Skills Between Machines

If you manage more than one profile or machine, snapshots export the whole installed set to a file:

hermes skills snapshot export   # export installed skills to a file
hermes skills snapshot import   # import and install skills from a file

That’s the reproducible path: export once, import on the next machine, done. It beats re-installing every skill by hand.

Syncing Skills Across a Team

For teams, the dedicated command is hermes sync — Skill Sync, which syncs your skills across devices and with teammates. The snapshot flow is fine for one-off migrations; hermes sync is the ongoing channel for a shared skill set, so a runbook or style skill can be maintained once and picked up everywhere.

Publishing Your Own Skill

When a skill proves itself, you can publish it to a registry with hermes skills publish. Publishing a skill means writing good frontmatter quality so other agents beyond Hermes can adopt it — the same SKILL.md convention is becoming a cross-tool standard, so one well-written skill can serve multiple agents.

Writing Your First Skill

1. Create skills/my-skill/SKILL.md with frontmatter (name, description — the description is what routing matches against, so be specific)
2. Add scripts/, templates/, and references/ as needed
3. Test it locally until the flow is repeatable
4. Install it: hermes skills install ./skills/my-skill --name my-skill
5. For the team: hermes skills snapshot export or hermes sync

Skills bridge the gap between a general-purpose assistant and a specialized tool that knows your exact workflows — and because they live in plain Markdown, they’re version-controllable, reviewable in pull requests, and shareable across your team.

Related articles

• Claude Code Alternatives in 2026: 12 Options Compared
• Context Engineering for Coding Agents: How to Make Every Token Count
• The AI Coding Trust Paradox: 42% of Code Is AI-Generated, But Only 29% of Developers Believe It

Related: the Hermes console dashboard guide covers the monitoring side of running agents, and the 2026 coding agent security checklist has the hardening steps to pair with any skill install.