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 iwasa-kosui/kamae-ts --skill kamaegit clone --depth 1 https://github.com/iwasa-kosui/kamae-tsWrote 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/iwasa-kosui/kamae-ts/kamae)<a href="https://agentmods.dev/skills/iwasa-kosui/kamae-ts/kamae"><img src="https://agentmods.dev/badge/skills/iwasa-kosui/kamae-ts/kamae/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/iwasa-kosui/kamae-ts/kamae"><img src="https://agentmods.dev/badge/skills/iwasa-kosui/kamae-ts/kamae.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
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 | $0.00124 | $0.01359 |
| Opus 5 | $0.00062 | $0.00679 |
| Sonnet 5 | $0.00025 | $0.00272 |
| Haiku 4.5 | $0.00012 | $0.00136 |
Grade A, and why
kamae 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 4d 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.
How it starts
The opening of the file, as written. The whole thing — 93 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Kamae — Functional Domain Modeling in TypeScript
Six topic files cover the principles. Read only the file(s) relevant to the current task. The library guides under result-libraries/ and validation-libraries/ are read on demand based on the project's package.json.
Step 0: Load applicable rules
Before any other step, glob and Read rules in priority order:
.claude/rules/*.md(project-level overrides at the working-tree root)~/.claude/rules/*.md(user-global preferences)../../rules/defaults/*.mdrelative to thisSKILL.md(plugin defaults)
For each file:
- Read the YAML frontmatter. Skip the rule unless
applies-toiskamaeor*. - Group by
name. For eachname, keep only the highest-tier instance (1 > 2 > 3); within a tier the lexicographically last filename wins. - Apply the body of each surviving rule throughout the remaining steps. A
library-preferencerule overrides Step 1 detection; aconventionrule shapes generated code; anoverriderule replaces guidance from a specific topic file.
If no rules are found, proceed with the plugin defaults already documented in ../../rules/defaults/.
See ../../rules/README.md for the rule format.
Before applying the topic and library guides, inspect nearby files in the same package for an established, consistent coding and import style. Follow that local convention when it exists; use Kamae's guide conventions only when the repository does not establish one.
Step 1: Detect project libraries
Read package.json once. Note which Result library and validation library are present:
- Result libraries — match the first present in priority
neverthrow>byethrow>fp-ts>option-t. Load the matching guide underresult-libraries/when error-handling is in scope. - Validation libraries — match the first present in priority
zod>valibot>arktype. Load the matching guide undervalidation-libraries/when boundary or branded-type work is in scope.
What ships with it
19 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.
- boundary-defense.md 12 KB
- declarative-style.md 1.8 KB
- domain-modeling.md 10 KB
- error-handling.md 6.7 KB
- examples/sensitive-type-arktype.ts 1.5 KB runs code
- examples/sensitive-type-valibot.ts 1.5 KB runs code
- examples/sensitive-type.ts 1.4 KB runs code
- examples/taxi-request-arktype.ts 4.3 KB runs code
- examples/taxi-request-valibot.ts 3.9 KB runs code
- examples/taxi-request.ts 4.0 KB runs code
- result-libraries/byethrow.md 6.0 KB
- result-libraries/fp-ts.md 8.2 KB
- result-libraries/neverthrow.md 4.4 KB
- result-libraries/option-t.md 4.5 KB
- state-modeling.md 8.2 KB
- test-data.md 970 B
- validation-libraries/arktype.md 3.1 KB
- validation-libraries/valibot.md 2.9 KB
- validation-libraries/zod.md 3.0 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.
- 4d ago Changed · +7 lines 0618096843d6
- 11d ago First seen · 86 lines · 124 tokens per session scan A 000e8ccfa3f3
kamae is a skill published in the GitHub repository iwasa-kosui/kamae-ts (55 stars, last pushed 4d ago), licensed MIT. It adds 124 tokens to every session and 1,359 once invoked, about $0.0006 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.
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