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 ashtanko/kotlin-app-template --skill kotlin-functionsgit clone --depth 1 https://github.com/ashtanko/kotlin-app-templateWrote 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/ashtanko/kotlin-app-template/kotlin-functions)<a href="https://agentmods.dev/skills/ashtanko/kotlin-app-template/kotlin-functions"><img src="https://agentmods.dev/badge/skills/ashtanko/kotlin-app-template/kotlin-functions/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/ashtanko/kotlin-app-template/kotlin-functions"><img src="https://agentmods.dev/badge/skills/ashtanko/kotlin-app-template/kotlin-functions.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 | $0.00036 | $0.00890 |
| Opus 5 | $0.00018 | $0.00445 |
| Sonnet 5 | $0.00007 | $0.00178 |
| Haiku 4.5 | $0.00004 | $0.00089 |
Grade A, and why
kotlin-functions 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.
Copies of this mod
1 near-identical copy found in the catalogue:
- kotlin-functions — 92% identical, 7 lines differ
How it starts
The opening of the file, as written. The whole thing — 97 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Kotlin function ownership
Core principle
Put a function on the smallest accurate semantic owner. Extension syntax changes call shape, not ownership.
Reject primitive, common, and library-owned extensions by default: they create false ownership, domain pollution, noisy completion/imports, and collisions.
Procedure
Apply in order.
1. Name the semantic owner
Name the operation and the concept that owns it. If ownership is unclear, stop before selecting syntax.
2. Reject a misleading receiver early
For String, primitives, collections, Flow, framework, or third-party receivers, require all:
- Narrow
private/internalcohesive scope. - Valid for every receiver value.
- No policy, state, I/O, or dependency.
- Materially clearer receiver syntax.
- No better project-owned owner.
Any failure forbids an extension on that receiver; choose a non-extension form in step 3. private fun <T> MutableList<T>.swap(...) can pass: it is list-native, policy-free, and algorithm-local.
3. Choose the function form
| Meaning | Prefer |
|---|---|
| Project-owned intrinsic behavior | Member |
| Cross-type, stateless operation | Top-level function |
| Construction or parsing | Target factory or named top-level function |
| Retained policy, state, I/O, clock, locale, or dependencies | Injected service/collaborator |
| Type-native operation with a clearer receiver and every step-2 gate passed | Extension |
Use a service/collaborator only when behavior retains policy, state, I/O, clock/locale, or dependencies; otherwise use explicit parameters on a stateless function. Inject the collaborator through the constructor (see this project's dispatcher-injection convention in ../../reference/coding-conventions.md) rather than reaching for a singleton.
4. Move behavior and callers
Move the implementation, then update calls, imports, and function references. Preserve or deprecate public entry points unless this is an explicit breaking release; add non-public migration support only for concrete consumers.
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 · 97 lines · 36 tokens per session scan A 1058f2afbf40
kotlin-functions is a skill published in the GitHub repository ashtanko/kotlin-app-template (41 stars, last pushed 4d ago), licensed Apache-2.0. It adds 36 tokens to every session and 890 once invoked, about $0.0002 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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