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 travisjneuman/.claude --skill kotlin-multiplatformgit clone --depth 1 https://github.com/travisjneuman/.claudeWrote 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/travisjneuman/.claude/kotlin-multiplatform)<a href="https://agentmods.dev/skills/travisjneuman/.claude/kotlin-multiplatform"><img src="https://agentmods.dev/badge/skills/travisjneuman/.claude/kotlin-multiplatform/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/travisjneuman/.claude/kotlin-multiplatform"><img src="https://agentmods.dev/badge/skills/travisjneuman/.claude/kotlin-multiplatform.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector warn
SkillSpector: 5 findings, up to medium
These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →
- medium Data Exfiltration · line 93 Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.Fix: Verify the destination URL is trusted and necessary. Remove or replace with documented APIs. Ensure no secrets, tokens, or PII are transmitted.
- medium Data Exfiltration · line 97 Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.Fix: Verify the destination URL is trusted and necessary. Remove or replace with documented APIs. Ensure no secrets, tokens, or PII are transmitted.
- medium Rogue Agent · line 118 Skill establishes unauthorized persistence across sessions via cron jobs, startup scripts, or state files. Session persistence allows an attacker to maintain access beyond the current interaction.Fix: Remove any persistence mechanisms (cron jobs, startup scripts, state files). Skills should not maintain state across sessions without explicit user consent.
- medium Agent Snooping · line 239 Skill enumerates or reads other installed skills. Access to other skills' SKILL.md files or the skills directory reveals prompt instructions, capabilities, and secrets that should be invisible to peer skills.Fix: Remove all code or instructions that list or read other skills' files or directories. Skills should operate independently; cross-skill access is a privilege escalation.
- medium Agent Snooping · line 240 Skill enumerates or reads other installed skills. Access to other skills' SKILL.md files or the skills directory reveals prompt instructions, capabilities, and secrets that should be invisible to peer skills.Fix: Remove all code or instructions that list or read other skills' files or directories. Skills should operate independently; cross-skill access is a privilege escalation.
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 | $0.00054 | $0.01448 |
| Opus 5 | $0.00027 | $0.00724 |
| Sonnet 5 | $0.00011 | $0.00290 |
| Haiku 4.5 | $0.00005 | $0.00145 |
Grade A, and why
kotlin-multiplatform 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 7d 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 — 246 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Kotlin Multiplatform Skill
Shared business logic and optional shared UI across Android, iOS, desktop, and web.
Project Structure
project/
├── composeApp/ # Shared Compose UI (if using CMP)
│ └── src/
│ ├── commonMain/ # Shared UI code
│ ├── androidMain/ # Android-specific UI
│ ├── iosMain/ # iOS-specific UI
│ └── desktopMain/ # Desktop-specific UI
├── shared/ # Shared business logic (KMP)
│ └── src/
│ ├── commonMain/ # Shared code
│ │ └── kotlin/
│ │ ├── data/ # Repositories, data sources
│ │ ├── domain/ # Use cases, models
│ │ └── platform/ # expect declarations
│ ├── androidMain/ # actual implementations
│ ├── iosMain/ # actual implementations
│ └── commonTest/ # Shared tests
├── androidApp/ # Android entry point
├── iosApp/ # iOS entry point (Xcode project)
├── build.gradle.kts
└── settings.gradle.kts
expect/actual Pattern
// commonMain - expect declaration
expect class PlatformContext
expect fun getPlatformName(): String
expect fun createHttpClient(): HttpClient
// androidMain - actual implementation
actual class PlatformContext(val context: android.content.Context)
actual fun getPlatformName(): String = "Android ${Build.VERSION.SDK_INT}"
actual fun createHttpClient(): HttpClient = HttpClient(OkHttp) {
install(ContentNegotiation) { json() }
}
// iosMain - actual implementation
actual class PlatformContext
actual fun getPlatformName(): String = UIDevice.currentDevice.systemName()
actual fun createHttpClient(): HttpClient = HttpClient(Darwin) {
install(ContentNegotiation) { json() }
}
Key Libraries
| Library | Purpose | Multiplatform? |
|---|---|---|
| Ktor | HTTP client | Yes |
| kotlinx.serialization | JSON parsing | Yes |
| kotlinx.coroutines | Async/concurrency | Yes |
| SQLDelight | Local database | Yes |
| Koin | Dependency injection | Yes |
| Compose Multiplatform | Shared UI | Yes |
| kotlinx.datetime | Date/time | Yes |
| Napier | Logging | Yes |
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.
- 7d ago First seen · 246 lines · 54 tokens per session scan A e245dc1bfaf3
kotlin-multiplatform is a skill published in the GitHub repository travisjneuman/.claude (97 stars, last pushed 6d ago), licensed MIT. It adds 54 tokens to every session and 1,448 once invoked, about $0.0003 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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