AugmentClaude
BackendPM

Create Harness

By ruvnet· ruvnet/agent-harness-generator· 0

Scaffold a custom AI agent harness with CLI, MCP server, and marketplace identity.

Installation

  1. Make sure Claude is on your device and in your terminal.

    Skills load from ~/.claude/skills/ when Claude Code starts up — so you need it on your machine first. If you don't have it yet, install it once with the command below, then run claude in any terminal to verify.

    One-time setup
    npm i -g @anthropic-ai/claude-code

    Already have it? Skip ahead.

  2. Paste into Claude Code or into your terminal.
    Install
    Sign up to copy
    Sign up free to reveal

    This copies the whole skill folder into ~/.claude/skills/create-harness-ruvnet/ — the SKILL.md plus any scripts, reference docs, or templates the skill ships with. Safe default: works for every skill.

    Faster alternative (instruction-only skills)

    Skips the clone and grabs only the SKILL.md file. Don't use this if the skill ships Python scripts, reference markdowns, or asset templates — they won't be downloaded and the skill will fail when it tries to load them.

    Quick install (SKILL.md only)
    Sign up to copy
    Sign up free to reveal
  3. Restart Claude Code.

    Quit and reopen Claude Code (or any other agent that loads from ~/.claude/skills/). New skills are picked up on startup.

  4. Just ask Claude.

    Skills auto-activate when your request matches the skill's description — no slash command needed. Trigger phrases live in the skill's own frontmatter; you can read them in the “What this skill does” section above.

Prefer to read the source first? Open on GitHub.

When Claude uses it

Scaffold your own focused AI agent harness — pick host (Claude Code, Codex, pi.dev, Hermes), template, agents, skills, and ship a npm-publishable harness with its own npx CLI. Use when a user asks to "create my own agent harness", "scaffold a harness", "make a custom Claude Code plugin like ruflo", or "build a vertical AI assistant for X".

What this skill does

create-harness

This skill scaffolds an AI agent harness — your own focused, branded harness with its own npx <name> CLI, MCP server registration, memory namespace, learning loop, and marketplace identity.

When to use this skill

Use this skill when the user wants any of:

  • A custom MCP-server-backed AI assistant (legal, trading, support, ops, …)
  • A Claude Code plugin that bundles their own agents/skills/prompts
  • A Codex skill that wraps a kernel + tools
  • A pi.dev extension or Hermes agent runtime config
  • A standalone npm package they can npm publish under their own scope

How to invoke

/create-harness

The skill asks for:

  1. Harness name (kebab-case, e.g. legal-redline)
  2. Description (one line)
  3. Host(s) — Claude Code, Codex, pi.dev, Hermes (multi-select)
  4. Template — minimal (default), vertical:trading, vertical:support, vertical:devops, vertical:legal, vertical:research, or eject-from-ruflo
  5. Memory backend — AgentDB (default), SQLite-only, in-memory
  6. Routing strategy — 3-tier (default) or single-tier
  7. Marketplace — independent (no ruflo branding) or powered-by

Under the hood

Calls npx create-agent-harness <name> with the user's choices, copies the chosen template into the current directory, runs the post-generation smoke test, and emits a .harness/manifest.json so future updates can harness upgrade cleanly (copier-style regenerate-diff-merge).

Outputs

FilePurpose
package.jsonThe harness's npm package, ready to npm publish
bin/<name>.jsThe CLI binary your users invoke
.claude/settings.json (if Claude Code host)MCP + hooks wiring
.codex/config.toml (if Codex host)MCP table in TOML
AGENTS.md + SYSTEM.md (if pi.dev host)Pi extension instructions
cli-config.yaml (if Hermes host)Hermes runtime config
.harness/manifest.jsonGenerator state — drives drift detection (ADR-008)
witness.jsonEd25519-signed provenance manifest (ADR-011)

After scaffolding

The user can:

cd <name>
npm install
npm test
npm publish              # ship their harness to npm
# their users: npx <name> init

Notes for the model

  • This is a deterministic operation — defer to create-agent-harness for the actual file creation, do NOT generate harness file contents yourself
  • The witness manifest is required — do not skip it
  • If the user asks for "ruflo for X" or "my own ruflo", recommend vertical:<X> templates first and offer minimal as the fallback
  • Multi-host is supported but increases the harness's surface area — recommend single-host for first-time users unless they explicitly need multi-host

Related skills

G

Generative Code Art

anthropics

Create algorithmic art with p5.js using randomness and interactive parameters.

OfficialComplete terms in LICENSE.txt
P

Poster & Visual Design

anthropics

Create original posters and visual art in PNG and PDF formats.

OfficialComplete terms in LICENSE.txt
C

Claude API Helper

anthropics

Build, debug, and optimize Claude API applications with caching and model migration support.

OfficialComplete terms in LICENSE.txt
M

MCP Server Builder

anthropics

Build protocol servers that connect language models to external APIs and services.

OfficialComplete terms in LICENSE.txt