Better Harness is an open-source platform for studying and improving how coding agents work on tasks, using written harnesses, controlled tests, and evidence from projects and sessions. Coding teams use it to identify workflow problems and turn them into prioritized improvements and verifiable next steps. Its catalogue entries extend coding-agent workflows for supported hosts such as Claude Code, Codex, Cursor, and others.
Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx agentmods add skills/qoderai/better-harness/skill-reviewnpx skills add QoderAI/better-harness --skill skill-reviewgit clone --depth 1 https://github.com/QoderAI/better-harnessWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/qoderai/better-harness/skill-review)<a href="https://agentmods.dev/skills/qoderai/better-harness/skill-review"><img src="https://agentmods.dev/badge/skills/qoderai/better-harness/skill-review.svg" alt="Measured on agentmods" height="20"></a>What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5 | $0.00050 | $0.00692 |
| Opus 5 | $0.00025 | $0.00346 |
| Sonnet 5 | $0.00010 | $0.00138 |
| Haiku 4.5 | $0.00005 | $0.00069 |
Grade A, and why
skill-review scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 5d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 68 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Skill Review
Review a skill as an execution contract, not as prose. Trace how an agent would enter, load, delegate, produce artifacts, and verify results; then report the smallest changes that would improve that chain.
Review Workflow
- Resolve the target skill or prompt chain. If the user names a path, stay on that path and its directly linked resources.
- Read repo instructions first: nearest
AGENTS.md, plugin manifests, and the targetSKILL.mdfrontmatter/body. - Trace the chain from entrypoint to references, templates, scripts, detectors, tests, generated artifacts, and validation commands. Build an ownership map: what file owns workflow, output structure, runtime rules, style, and tests.
- Audit the contract before editing. Use Audit Checklist and Reference Patterns as lenses.
- If the user asked for changes, patch only the smallest owning files. Keep
generated helpers, smoke scripts, and local experiments outside
SKILL.mdunless they are durable resources the skill must use. - Validate with the lightest real gate available: skill validator, repo tests, plugin validation, or a bounded agent smoke. State any gate that could not be run.
Use subagents only as an evaluation surface or for independent broad research. The lead agent owns the review, final calibration, and file edits. Pass raw artifacts and task-local scope to subagents; do not pass the intended answer.
Review Lenses
- Audit Checklist: trigger contract, progressive disclosure, workflow/delegation, template ownership, readability, evidence.
- Reference Patterns: reusable design lenses such as Trigger/Protocol split, Gate Function, and Output Contract Slots.
- Fast Inspection Commands: starting
rg,wc, andgit diff --checkprobes adapted to the repo.
Finding Severity
What ships with it
3 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 5d ago First seen · 68 lines · 50 tokens per session scan A 273ae4e704cb
skill-review is a skill published in the GitHub repository QoderAI/better-harness (2,164 stars, last pushed yesterday), licensed MIT. It adds 50 tokens to every session and 692 once invoked, about $0.0003 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
Other skills, from other repositories
capability-recommender
Use when the need is read-only capability design only: skills, hooks, MCP servers, subagents, plugins, scripts, or CI/headless automation. For cross-surface workbench bootstrap or repair, use harness-builder.
plan
用于把已批准 Spec 或足够明确的非平凡请求转成 Executable Plan。触发条件：需要 active slice、planning surface、验证路径、能力缺口或 commit unit。不要在需求/验证策略不清时使用；先回 brainstorm。项目工作面不清时转 harness-builder。.
agent-instructions-maintainer
Use when durable agent instructions need audit or repair only: AGENTS.md, CLAUDE.md, .claude.md, .claude.local.md, canonical rules/.mdc, or Cursor rule mirrors. For cross-surface workbench bootstrap or repair, use harness-builder.
find-skills
Use this helper to discover reusable agent skills for a clear task or capability gap. Trigger it when the user asks how to do X, find a skill, or extend agent capabilities. Do not install or adopt a skill just because it is related; project adoption belongs to harness-builder.
harness-builder
Use when a project workbench needs bootstrap, repair, or cross-surface recommendation: route entry, recovery, verification, capability, install, and anti-entropy gaps. Thick work goes to capability-recommender, agent-instructions-maintainer, or recovery-surface-builder.
implement
用于在一个 scoped active slice 上做最小代码或文档改动。触发条件：用户请求/Spec/Executable Plan 已清楚，工作面和验证路径足够明确。不要在需求、active slice、根因或工作面不清时使用；局部检查只是反馈，ready 只能交给 verify。.