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 simota/agent-skills --skill buildergit clone --depth 1 https://github.com/simota/agent-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/simota/agent-skills/builder)<a href="https://agentmods.dev/skills/simota/agent-skills/builder"><img src="https://agentmods.dev/badge/skills/simota/agent-skills/builder/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/simota/agent-skills/builder"><img src="https://agentmods.dev/badge/skills/simota/agent-skills/builder.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector warn
SkillSpector: 1 finding, up to high
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 →
- high Prompt Injection · line 6 Hidden instructions were detected in comments or invisible text. These could contain malicious directives. Manual review is recommended.Fix: Audit all comments and invisible characters. Remove any instructions that direct the agent to perform unauthorized actions. Use plain, reviewable content.
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 | $0.00040 | $0.05136 |
| Opus 5.5 | $0.00016 | $0.02054 |
| Sonnet 5.5 | $0.00008 | $0.01027 |
| Haiku 4.5 | $0.00004 | $0.00514 |
Grade A, and why
builder 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 3d 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:
- builder — 97% identical, 35 lines differ
The source is not reproduced here
Licensed MIT
The repository is licensed MIT, which this catalogue does not treat as permission to reproduce the file. Read it at the source.
What ships with it
28 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.
- _common 10 B
- reference/_common 13 B
- reference/autorun-nexus.md 3.3 KB
- reference/autorun-schema.md 1.0 KB
- reference/builder 13 B
- reference/cli-tui/cli-design-anti-patterns.md 8.7 KB
- reference/cli-tui/tui-components.md 9.2 KB
- reference/cross-language-port.md 4.3 KB
- reference/external-integration.md 6.5 KB
- reference/grammar/ast-transforms.md 14 KB
- reference/grammar/parser-generators.md 17 KB
- reference/grammar/regex-safety.md 17 KB
- reference/handoffs.md 1.5 KB
- reference/image-generation-api.md 8.7 KB
- reference/image-generation-batch.md 6.0 KB
- reference/image-generation-cinematic-prompts.md 16 KB
- reference/image-generation-codex.md 2.8 KB
- reference/image-generation-content-safety.md 15 KB
- reference/image-generation-postprocess.md 7.2 KB
- reference/image-generation-prompts.md 6.6 KB
- reference/image-generation-provenance.md 13 KB
- reference/image-generation-style-transfer.md 6.8 KB
- reference/implementation-policy.md 6.5 KB
- reference/pair-programming.md 5.2 KB
- reference/recipe-verify-gates.md 5.4 KB
- reference/recipes-index.md 3.3 KB
- reference/reference-index.md 3.1 KB
- reference/targeted-patch.md 3.5 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.
- 3d ago Changed · -1 lines ebf240df2e04
- 5d ago Changed 6c1c3ab1d994
- 8d ago Changed d33a5adaf03b
- 1mo ago Changed · -2 lines ed2df2f9eafb
- 1mo ago Changed · -3 lines 0ba928f1ba6a
- 1mo ago First seen · 303 lines · 40 tokens per session scan A 1a69c867e929
builder is a skill published in the GitHub repository simota/agent-skills (93 stars, last pushed yesterday), licensed MIT. It adds 40 tokens to every session and 5,136 once invoked, about $0.0002 per session on Opus 5.5. 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.
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