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 jxoesneon/Ciel --skill kotlin-developmentgit clone --depth 1 https://github.com/jxoesneon/CielWrote 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/jxoesneon/ciel/kotlin-development)<a href="https://agentmods.dev/skills/jxoesneon/ciel/kotlin-development"><img src="https://agentmods.dev/badge/skills/jxoesneon/ciel/kotlin-development/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/jxoesneon/ciel/kotlin-development"><img src="https://agentmods.dev/badge/skills/jxoesneon/ciel/kotlin-development.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 | $0.00025 | $0.00573 |
| Opus 5 | $0.00013 | $0.00287 |
| Sonnet 5 | $0.00005 | $0.00115 |
| Haiku 4.5 | $0.00003 | $0.00057 |
Grade A, and why
kotlin-development 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 8d 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
CIEL ADAPTATION: Kotlin Development (Idiomatic & Async)
This skill formalizes the "Modern JVM" layer. it prioritizes null safety, expression-oriented code, and structured concurrency.
Idiomatic Standards
- Null Safety: Leverage
?.and?:. Prohibit!!. - Type System: Use
sealed class/interfacefor exhaustive state modeling. Usevalue classfor zero-overhead wrappers. - Expressions: Favor expression bodies (
fun x() = ...) andwhenas an expression. - Scope Functions: Use
applyfor config,letfor transformation,alsofor side effects.
Structured Concurrency (Async Layer)
- Scope: Never use
GlobalScope. UseviewModelScope,lifecycleScope, orcoroutineScope {}. - Parallelism: Use
async { ... }.await()for concurrent data loading. - Reactivity:
- StateFlow: For UI state (use
WhileSubscribed(5000)). - SharedFlow: For one-time effects (Snackbars, Navigation).
- StateFlow: For UI state (use
- Dispatchers:
Defaultfor CPU,IOfor I/O,Mainfor UI.
Testing (Kotest & MockK)
- Spec Style: Standardize on
BehaviorSpec(Given/When/Then) for complex logic;StringSpecfor units. - Mocking: Use
coEveryandcoVerifyfor suspend functions. - Flow Testing: Use
turbineto test Flow emissions.
Anti-Patterns
- Platform Leakage: Passing Java-style
nullpointers without checking at boundaries. - Thread.sleep: Using sleep in coroutine tests (use
advanceTimeBy). - Fat Composable: Performing heavy Flow creation/logic directly in UI functions without
remember.
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.
- 8d ago First seen · 54 lines · 25 tokens per session scan A addbc8b8f2e5
kotlin-development is a skill published in the GitHub repository jxoesneon/Ciel (1 stars, last pushed 4d ago), licensed Apache-2.0. It adds 25 tokens to every session and 573 once invoked, about $0.0001 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 2026-09-03.
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