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 Sounio-lang/sounio --skill sounio-stdlib-devgit clone --depth 1 https://github.com/Sounio-lang/sounioWrote 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/sounio-lang/sounio/sounio-stdlib-dev)<a href="https://agentmods.dev/skills/sounio-lang/sounio/sounio-stdlib-dev"><img src="https://agentmods.dev/badge/skills/sounio-lang/sounio/sounio-stdlib-dev/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/sounio-lang/sounio/sounio-stdlib-dev"><img src="https://agentmods.dev/badge/skills/sounio-lang/sounio/sounio-stdlib-dev.svg" alt="Reviewed on agentmods" width="80" 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 5.1 | $0.00053 | $0.00263 |
| Opus 5.5 | $0.00021 | $0.00105 |
| Sonnet 5.5 | $0.00011 | $0.00053 |
| Haiku 4.5 | $0.00005 | $0.00026 |
Grade A, and why
sounio-stdlib-dev 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 1mo 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.
What it actually says
Sounio Stdlib Dev
Overview
Make focused, idiomatic changes to the Sounio standard library and keep the repo’s stdlib reference accurate.
Workflow
1) Find the right module and baseline
- Start from
STDLIB_REFERENCE.mdto understand intended module status and scope. - Mirror patterns from the module’s existing files before introducing new idioms.
2) Keep Sounio syntax consistent
- Prefer canonical syntax rules from
CLAUDE.mdanddocs/guide/LLM_PROGRAMMING_GUIDE.md. - If the compiler does not support a feature yet, avoid using it in stdlib unless it is explicitly “parser-only”.
3) Add tests where possible
- Add a small regression in
tests/run-pass/or module-local tests if the project uses them. - Keep doc examples either compilable or clearly marked aspirational.
References
- Stdlib map:
references/stdlib-navigation.md
What ships with it
1 file 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.
- 1mo ago Changed 0fe94e53ff2a
- 1mo ago First seen · 32 lines · 53 tokens per session scan A 4cecb72f904e
sounio-stdlib-dev is a skill published in the GitHub repository Sounio-lang/sounio (12 stars, last pushed today), licensed Apache-2.0. It adds 53 tokens to every session and 263 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 2026-08-31.
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