Best of Agent Harnesses is a curated directory of agent harnesses, which are runtimes that let AI models act by controlling tools, permissions, context, and saved state around an action loop. It helps people compare harnesses and use related templates, playbooks, and learning resources for building agentic systems. Catalogue entries include agents and other configurations that can query or support the listed harnesses.
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.
git clone --depth 1 https://github.com/RyanAlberts/best-of-Agent-HarnessesWrote 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/plugins/ryanalberts/best-of-agent-harnesses/harness-skills)<a href="https://agentmods.dev/plugins/ryanalberts/best-of-agent-harnesses/harness-skills"><img src="https://agentmods.dev/badge/plugins/ryanalberts/best-of-agent-harnesses/harness-skills/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/plugins/ryanalberts/best-of-agent-harnesses/harness-skills"><img src="https://agentmods.dev/badge/plugins/ryanalberts/best-of-agent-harnesses/harness-skills.svg" alt="Reviewed on agentmods" width="80" height="20"></a>Grade A, and why
harness-skills 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 6d 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.
The source is not reproduced here
Licensed CC-BY-SA-4.0
The repository is licensed CC-BY-SA-4.0, which this catalogue does not treat as permission to reproduce the file. Read it at the source.
What it installs
The manifest is a name and a version. 10 skills travel with it, and installing the plugin installs all of them — 1,534 tokens a session between them. Each is measured on its own page, and each can be installed alone.
- Skill agents-md-checker A 158 tokens
- Skill harness-test-drive A 153 tokens
- Skill regression-finder A 147 tokens
- Skill rules-to-guards A 156 tokens
- Skill runaway-guard A 155 tokens
- Skill tool-design-checker A 149 tokens
- Skill claim-check A 151 tokens
- Skill session-waste-report A 135 tokens
- Skill sandbox-check B 174 tokens
- Skill guardrail-tester C 156 tokens
What ships with it
1 file beside marketplace.json#harness-skills 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.
- 6d ago First seen · 37 lines scan A 6c33b99dfbd8
harness-skills is a plugin published in the GitHub repository RyanAlberts/best-of-Agent-Harnesses (1,232 stars, last pushed 4d ago), licensed CC-BY-SA-4.0. Its token cost is not measured: this kind of file is read by the harness, not the model. 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 2026-10-10.
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