When to use this skill
Use it when the job is improving the harness around a fixed model — not its weights — and the evidence must come from executions: run the upstream pipeline, budget it, judge it, or apply its Propose–Probe–Compose method to a project's own agent instructions, skills, subagents, or hooks. Designing an agent team belongs here as method mode: a team is the subagents component plus the routing text that triggers it, and each role must win a probe.
Route out: reusable SKILL.md ratcheting → skill-autoresearch; coordination-failure evals for
an existing multi-agent system → multi-agent-eval-harness; production traces →
agent-observability; running a team on a runtime → paperclip, ruflo, or zeroshot.
Instructions
- Run the offline gate first. From the repository root:
python3 .agent-skills/harness2/scripts/preflight.py --json; from an installed skill root:python3 "$SKILLS_ROOT/harness2/scripts/preflight.py" --json. Use--bench methodfor manual method mode (host facts only; no tool is required), or--bench lab|jb|wbwith--substrate oc|cx; add--repo PATH --expect-commit 1cfe254e8d25b15f37048c3730134686abe60335for a supplied checkout. It never runs harness2, setup, a model, Docker, or the network, and it reports.envpresence without reading it. - Pick one mode and load references/upstream.md for its commands:
demo(credential-free proof of the workflow),benchmark(setup → check → run → judge → report),bridge(Codex executor via Vertex), ormethod(manual application — load references/method-mode.md). - Demo only when the mode needs upstream code. For
demoor before a firstbenchmarkengagement, get approval for the install (a git clone,uv venv --python 3.12 .venv— which may download CPython — anduv pip install -e '.[render]'from PyPI), then runharness2-demo --output runs/demo --k 2; it makes no model calls and writes only--output.methodmode and fit checks need no checkout, install, or demo. - Gate every benchmark side effect. Get explicit approval before
harness2-setup(pinned clones, npm/Bun,uv sync, dataset and Docker image downloads), before any refinement or judge run (paid Vertex calls; about4kexecutor rollouts and3kimprover sessions per task), and beforeharness2-bridge(starts a server;--host 0.0.0.0binds all interfaces). Preview withharness2-setup <bench> --dry-runandharness2 ... --dry-run; cap scope with--only-domainsand--max-tasks(per domain, not global). Read WorkBuddy's territorial license before downloading it. - Isolate the executor. Codex runs with its sandbox disabled and executors have open network
access; public rubrics have been fetched by a rollout. Before a scored run, block
huggingface.co,hf.co,*.hf.co,github.com, andraw.githubusercontent.comat the network layer and report that restriction. - Keep run identity fixed. Judge and report with the same
--bench,--subset,--substrate,--k,--mode, and--seedas the run; use a newHARNESS2_RUNS_DIRwhen models or task selection change. Write.envfrom the documented keys yourself — the pinned commit does not track the.env.exampleits docs mention — and never echo credential values. - Report evidence, not paper numbers. Return exact commands, pin, mode,
k, task cap, executor/improver/judge IDs, network restriction, exit status (0ok,2some tasks failed,1config/dead domain/zero tasks), and the adopted-harness paths.harness2-checkpassing does not prove model access; a failed judge is unscored, never zero.
Examples
python3 .agent-skills/harness2/scripts/preflight.py --json # offline gate
harness2-demo --output runs/demo --k 2 # after install approval; no credentials or models
python3 .agent-skills/harness2/scripts/preflight.py --bench lab --json
harness2-setup lab --dry-run # preview only
# after approval of setup, cost, and executor network restriction:
harness2 --bench lab --k 1 --mode parallel --only-domains antitrust-competition --max-tasks 1
harness2-judge --bench lab --k 1 --mode parallel
harness2-report --bench lab --k 1 --mode parallel
Best practices
- Before a first benchmark engagement, prefer the approved local demo; it exercises the real recursion and library code without model cost. Method mode never requires it.
- Spend budget on one domain and one task before widening; compare parallel and sequential only with task selection, models, judge, and network restriction held fixed.
- Keep always-on text (system prompt, guardrails, memory, tool guidance) inside the substrate cap; move detail into skills with explicit trigger lines.
- In method mode, every new subagent, skill, or hook must win an execution probe; record the adopted diff and the evidence in a per-domain library entry.