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 skills add seaworld008/Commonly-used-high-value-skills --skill arenagit clone --depth 1 https://github.com/seaworld008/Commonly-used-high-value-skillsWrote 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/seaworld008/commonly-used-high-value-skills/arena)<a href="https://agentmods.dev/skills/seaworld008/commonly-used-high-value-skills/arena"><img src="https://agentmods.dev/badge/skills/seaworld008/commonly-used-high-value-skills/arena/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/skills/seaworld008/commonly-used-high-value-skills/arena"><img src="https://agentmods.dev/badge/skills/seaworld008/commonly-used-high-value-skills/arena.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector warn
SkillSpector: 2 findings, up to medium
These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →
- medium Excessive Agency · line 150 Skill enables autonomous high-impact decisions without human-in-the-loop verification. Critical operations (destructive commands, financial transactions, data deletion) should require explicit user confirmation.Fix: Add human-in-the-loop confirmation for destructive, irreversible, or high-impact operations. Never auto-execute commands that modify files, send data, or alter system state.
- medium Excessive Agency · line 153 Skill enables autonomous high-impact decisions without human-in-the-loop verification. Critical operations (destructive commands, financial transactions, data deletion) should require explicit user confirmation.Fix: Add human-in-the-loop confirmation for destructive, irreversible, or high-impact operations. Never auto-execute commands that modify files, send data, or alter system state.
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 5.1 | $0.00053 | $0.05216 |
| Opus 5 | $0.00026 | $0.02608 |
| Sonnet 5 | $0.00011 | $0.01043 |
| Haiku 4.5 | $0.00005 | $0.00522 |
Grade A, and why
arena 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.
Copies of this mod
1 near-identical copy found in the catalogue:
- arena — 91% identical, 101 lines differ
How it starts
The opening of the file, as written. The whole thing — 330 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Arena
"Arena orchestrates external engines — through competition or collaboration, the best outcome emerges."
Orchestrator not player · Right paradigm for task · Play to engine strengths · Data-driven decisions · Cost-aware quality · Specification clarity first
What ships with it
11 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.
- references/ai-code-quality-assurance.md 8.8 KB
- references/collaborate-mode-guide.md 20 KB
- references/competitive-development-patterns.md 9.3 KB
- references/decision-templates.md 8.7 KB
- references/engine-cli-guide.md 26 KB
- references/engine-prompt-optimization.md 8.3 KB
- references/evaluation-framework.md 22 KB
- references/execution-learning.md 15 KB
- references/multi-engine-anti-patterns.md 8.5 KB
- references/question-templates.md 3.8 KB
- references/team-mode-guide.md 22 KB
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 Changed · +2 lines 2e08d00f5f45
- 12d ago First seen · 328 lines · 53 tokens per session scan A 27cc6209f458
arena is a skill published in the GitHub repository seaworld008/Commonly-used-high-value-skills (70 stars, last pushed 5d ago), licensed MIT. It adds 53 tokens to every session and 5,216 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
elasticsearch
Query and analyze logs in Elasticsearch. Use this skill when the user wants to search logs, query log data, count log entries, filter by trace IDs, or analyze application logs stored in Elasticsearch. Common use cases include debugging requests by trace ID, finding error logs, analyzing request patterns, and…
svg-creator
Produce SVGs that are spec-correct (W3C SVG 2), CSS-independent, accessible when meaningful, safe to render in untrusted contexts, optimized in size, and readable enough to edit.
prompt-template-wizard
Rigorously collects and validates all fields needed to produce a complete, unambiguous prompt template for features and bug fixes. The skill asks targeted questions until the template is fully filled, consistent, and ready to paste into a Codex/GPT-5.2 coding session.
read-only-gh-pr-review
Review backend pull requests for correctness, security, performance, maintainability, and test coverage using GitHub CLI plus local repository inspection. Use when asked to review service-layer/API/database changes, audit backend branch diffs, summarize backend risk, or produce actionable must-fix/should-fix feedback.
german-elster-tax-filing
Use this skill to run a complete intake for a german personal income tax return in elster for tax years 2024 onward, estimate the tax result, and map the final values into the correct official forms and fields.
trello
Manage Trello boards, lists, and cards via the Trello REST API.