Open Harness is a Docker-based agent harness for one project, agent-tended over time. One docker compose up gives you a long-lived sandbox where Claude (or another agent of your choice) runs against a single repo, branch, and identity — not a multi-tenant comparison rig.
- One project, one sandbox. A single container scoped to a single repo. The agent owns its branch and its workspace; you keep your laptop clean.
- Agents that work while you sleep. A tiny croner runtime reads
crons/*.mdmarkdown and wakes the agent on a schedule. - Only host dependency: Docker. No Node, no Python, no toolchain rot on your laptop.
- Composable infra. Cherry-pick Postgres, Cloudflare tunnels, SSH, Slack, Caddy gateway via Compose overlays.
- Multi-agent? Add a pack. Slack-driven Pi+Mom and other multi-agent setups ship as separate packs — see
@ryaneggz/mifune.
curl -fsSL https://oh.mifune.dev/install.sh | bashThe installer clones into ~/.openharness, offers to share your host
gh token, writes .devcontainer/.env, and builds the image (~10 min
cold, ~30s warm). Only host dependency: Docker.
cd ~/.openharness
make shell # enter the isolated sandbox
# inside the sandbox, launch any core agent:
# claude # Claude Code (default)
# codex # OpenAI Codex CLI
# opencode # OpenCode
# pi # Pi Coding Agent
# deepagents # LangChain DeepAgents (multi-provider)
make destroy # stop and remove the sandbox
make help # all targetsPrefer VS Code or remote SSH? See Connecting to a sandbox.
.devcontainer/.env is generated with safe defaults during install. Open
it any time to change SANDBOX_NAME, set a different GH_TOKEN, change
TZ, or enable overlay-specific vars (SANDBOX_PASSWORD for sshd,
SLACK_* for the Slack overlay). Apply with make destroy && make sandbox.
Manual setup (no installer)
git clone https://github.com/ryaneggz/open-harness.git && cd open-harness
make sandbox
make shell| Core agents | Claude Code, Codex, OpenCode, Pi |
| Runtimes | Node 22, pnpm, Bun, uv (Python) |
| DevOps | Docker CLI + Compose, GitHub CLI, cloudflared, tmux, croner |
| Browser | agent-browser + Chromium (headless) |
| One project, one sandbox | A single container scoped to a single repo and branch |
| Crons | Markdown-defined schedules in crons/*.md driven by the in-container croner runtime |
| Multi-agent | Install a harness pack such as @ryaneggz/mifune for Pi+Mom + Slack |
- Quickstart — full step-by-step
- Onboarding — auth wizard walkthrough
- Compose overlays — Postgres, SSH, gateway, Cloudflare
- Bring your own harness — install harness packs (e.g.
@ryaneggz/mifunefor the Pi+Mom Slack bot) - Crons — markdown-defined autonomous tasks
- Architecture — one container, one project, one croner
See Repo Layout for the annotated tree.
For Pi+Slack functionality, install the @ryaneggz/mifune harness pack from inside the sandbox.
make destroyIssues and PRs welcome at github.com/ryaneggz/open-harness. If Open Harness is useful to you, please give us a star.
MIT.