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-epistemic-typesgit 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-epistemic-types)<a href="https://agentmods.dev/skills/sounio-lang/sounio/sounio-epistemic-types"><img src="https://agentmods.dev/badge/skills/sounio-lang/sounio/sounio-epistemic-types/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-epistemic-types"><img src="https://agentmods.dev/badge/skills/sounio-lang/sounio/sounio-epistemic-types.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 | $0.00071 | $0.00373 |
| Opus 5 | $0.00036 | $0.00187 |
| Sonnet 5 | $0.00014 | $0.00075 |
| Haiku 4.5 | $0.00007 | $0.00037 |
Grade A, and why
sounio-epistemic-types 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 12d 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 Epistemic Types
Overview
Make changes to Sounio’s epistemic system without breaking its invariants or collapsing uncertainty into confidence (or vice versa).
Workflow
1) Start from the invariants
- Read
stdlib/epistemic/SEMANTICS.mdand treat it as the spec for “what must never be violated”. - When changing semantics, update tests (or add new ones) that protect those invariants.
2) Locate the implementation layer you’re editing
- Frontend surface syntax / parsing:
compiler/src/ast/mod.rs,compiler/src/parser/,compiler/src/parser/tests/epistemic.rs - Core compiler epistemic structures:
compiler/src/epistemic/(e.g.,knowledge.rs,promotion.rs,kec.rs) - Dependent epistemic typing + subtyping proofs:
compiler/src/dependent/(e.g.,types.rs,subtyping.rs) - Stdlib semantics + user-facing APIs:
stdlib/epistemic/
3) Define purity/effects explicitly
- If an epistemic operation changes confidence or provenance, decide whether it must be effectful (and enforce via effect checking).
- Keep “confidence monotone under pure transforms” enforceable by construction.
References
- Epistemic map + search patterns:
references/epistemic-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.
- 12d ago First seen · 34 lines · 71 tokens per session scan A 08aec3bc573d
sounio-epistemic-types is a skill published in the GitHub repository Sounio-lang/sounio (6 stars, last pushed today), licensed Apache-2.0. It adds 71 tokens to every session and 373 once invoked, about $0.0004 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 2026-08-31.
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