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 eric861129/SKILLS_All-in-one --skill kotlin-specialistgit clone --depth 1 https://github.com/eric861129/SKILLS_All-in-oneWrote 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/eric861129/skills_all-in-one/kotlin-specialist)<a href="https://agentmods.dev/skills/eric861129/skills_all-in-one/kotlin-specialist"><img src="https://agentmods.dev/badge/skills/eric861129/skills_all-in-one/kotlin-specialist/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/eric861129/skills_all-in-one/kotlin-specialist"><img src="https://agentmods.dev/badge/skills/eric861129/skills_all-in-one/kotlin-specialist.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 | $0.00086 | $0.01345 |
| Opus 5.5 | $0.00034 | $0.00538 |
| Sonnet 5.5 | $0.00017 | $0.00269 |
| Haiku 4.5 | $0.00009 | $0.00135 |
Grade A, and why
kotlin-specialist 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.
This is a copy
94% identical to kotlin-specialist — 5 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.
How it starts
The opening of the file, as written. The whole thing — 148 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Kotlin Specialist
Senior Kotlin developer with deep expertise in coroutines, Kotlin Multiplatform (KMP), and modern Kotlin 1.9+ patterns.
Core Workflow
- Analyze architecture - Identify platform targets, coroutine patterns, shared code strategy
- Design models - Create sealed classes, data classes, type hierarchies
- Implement - Write idiomatic Kotlin with coroutines, Flow, extension functions
- Checkpoint: Verify coroutine cancellation is handled (parent scope cancelled on teardown) and null safety is enforced before proceeding
- Validate - Run
detektandktlint; verify coroutine cancellation handling and null safety- If detekt/ktlint fails: Fix all reported issues and re-run both tools before proceeding to step 5
- Optimize - Apply inline classes, sequence operations, compilation strategies
- Test - Write multiplatform tests with coroutine test support (
runTest, Turbine)
Reference Guide
Load detailed guidance based on context:
| Topic | Reference | Load When |
|---|---|---|
| Coroutines & Flow | references/coroutines-flow.md |
Async operations, structured concurrency, Flow API |
| Multiplatform | references/multiplatform-kmp.md |
Shared code, expect/actual, platform setup |
| Android & Compose | references/android-compose.md |
Jetpack Compose, ViewModel, Material3, navigation |
| Ktor Server | references/ktor-server.md |
Routing, plugins, authentication, serialization |
| DSL & Idioms | references/dsl-idioms.md |
Type-safe builders, scope functions, delegates |
Key Patterns
Sealed Classes for State Modeling
sealed class UiState<out T> {
data object Loading : UiState<Nothing>()
data class Success<T>(val data: T) : UiState<T>()
data class Error(val message: String, val cause: Throwable? = null) : UiState<Nothing>()
}
// Consume exhaustively — compiler enforces all branches
fun render(state: UiState<User>) = when (state) {
is UiState.Loading -> showSpinner()
is UiState.Success -> showUser(state.data)
is UiState.Error -> showError(state.message)
}
What ships with it
5 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.
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 First seen · 148 lines · 86 tokens per session scan A c026b7152c53
kotlin-specialist is a skill published in the GitHub repository eric861129/SKILLS_All-in-one (52 stars, last pushed 6mo ago), licensed MIT. It adds 86 tokens to every session and 1,345 once invoked, about $0.0003 per session on Opus 5.5. A static security scan graded it A with 0 findings. It is 94% identical to kotlin-specialist, differing in 5 lines, and is treated as a copy.
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