Ready to supercharge your AI agents?

Install any skill in seconds. Free to start, no credit card required.

Kotlin Specialist · paperclipai | DecimalAI

paperclipai/kotlin-specialist

SkillScore95Maintained

Provides idiomatic Kotlin patterns including coroutine concurrency, Flow streams, multiplatform architecture, Compose UI, Ktor servers, and type-safe DSL design.

codingby paperclipai

Links this skill to your agents and keeps it current with the author’s updates.

Automatic

Coding pack

1 · One-time — install the CLI (docs ↗)

pip install decimalai

2 · Get the skill — writes .claude/skills/paperclipai-kotlin-specialist/SKILL.md

decimalai skills pull paperclipai-kotlin-specialist --out .claude/skills/

No CLI? Get the same file — curl · raw file

curl -fsSL --create-dirs -o .claude/skills/paperclipai-kotlin-specialist/SKILL.md https://app.decimal.ai/s/paperclipai-kotlin-specialist/SKILL.md

Raw file: /s/paperclipai-kotlin-specialist/SKILL.md ↗ · machine-readable summary at /s/paperclipai-kotlin-specialist.json ↗

In productionGlobal

how this skill behaves on real traffic · last 30 days

Runs

all versions · 30d

Eval pass

100%

global

Used when offered

100%

used / offered · all versions

By model· real traffic, every org · 30d — not the benchmark

Model	Eval pass	Runs
gemini-3.6-flash	100%	6

Anonymized aggregate across every org using this skill — proof from real production use, not a demo.

Does this skill help? · Benchmark: with vs. withoutsign in to run this on your agents

22 test cases from the publisher’s eval.yaml · each run twice on gemini-3.6-flash — with the skill injected, then without · last run 54d ago

Yes — +5% lift-4% tokens0% turns95% of whole cases pass with skill (21/22)

Test case	Without → With	Effect	Δ tokens	Δ turns
case-13	✗→✓	▲ Improved	-24%	0%
case-01	✓→✓	＝ Same ✓	-17%	0%
case-02	✓→✓	＝ Same ✓	-6%	0%
case-03	✓→✓	＝ Same ✓	-8%	0%
case-05	✓→✓	＝ Same ✓	27%	0%

Showing 5 of 22 cases

SkillSafety

✓ 3 of 3 passed

Code scan15 of 15 checks clean

0 critical · 0 warning · 0 info — scanner v4 — 8/1/2026

live_secretremote_code_executionreverse_shelldata_exfiltrationssrf_metadataagent_snoopinganti_refusaldestructive_commandsobfuscated_unicodeunicode_homoglyphopaque_blobsuspicious_urltool_overreachtrigger_abuseprompt_injection_phrasing

IntentSafe

LLM judge · does the skill do what it claims

ContentClean

LLM judge · policy & harmful-content review

Source

Imported

paperclipai / companies

fullstack-forge/skills/kotlin-specialist/SKILL.md

View on GitHub ↗

Imported 8/1/2026Version v1

Skill contents

SKILL.md

name: kotlin-specialist description: > Provides idiomatic Kotlin patterns including coroutine concurrency, Flow streams, multiplatform architecture, Compose UI, Ktor servers, and type-safe DSL design. metadata: sources:

kind: github-file

repo: jeffallan/claude-skills path: skills/kotlin-specialist/SKILL.md commit: 3bf9a24b76a7c122f1fc05e83929fbc84e1c207a attribution: Jeffallan license: MIT usage: referenced

Illustrative Want to see what paperclipai/kotlin-specialist would put in front of your model? Preview the rendered body and check its trigger phrases — no LLM call, no signup.

Latest benchmark · publisher runVerified

8/4/2026, 17:21 UTC · 22 cases

Lift

+5%

95% vs 91%

Agent turns

1.0 vs 1.0

Tokens

-4%

1,857.09 vs 1,928.77

fail → pass · 1pass → pass · 20fail → fail · 1

Per-case results (22)

Case	Status	Duration (ms)			Turns			Tokens			Tool calls
Case	Status	Without	With	Δ	Without	With	Δ	Without	With	Δ	Without	With	Δ
case-01 I am writing a Kotlin background service that runs asynchronous database sync jobs triggered by user requests. I want to launch these jobs without blocking the caller. Should I use GlobalScope.launch to ensure they keep running even if the caller scope completes?	pass→pass	11,196	8,701	-22%	1	1	0%	2,120	1,766	-17%	0	0	—
case-02 I have a Kotlin Flow that reads data from a disk database inside a flow { ... } block. I want to execute the database reading logic on Dispatchers.IO. Should I wrap the inside of the flow block with withContext(Dispatchers.IO)?	pass→pass	9,297	6,831	-27%	1	1	0%	1,461	1,374	-6%	0	0	—
case-03 I am implementing a Kotlin coroutine that fetches data from three independent third-party APIs in parallel. If one API call fails with an exception, I want the other two API calls to complete normally rather than being cancelled. How should I structure the parent scope?	pass→pass	10,537	9,256	-12%	1	1	0%	2,112	1,944	-8%	0	0	—
case-04 I need to send one-time UI events (like showing a snackbar message or triggering navigation) from an Android ViewModel in Kotlin. Should I use StateFlow for these one-shot events?	fail→fail	13,023	12,947	-1%	1	1	0%	2,428	2,687	+11%	0	0	—
case-05 I am building a web service in Kotlin and need to define RESTful endpoints for /users to handle GET and POST requests. What is the idiomatic Kotlin server routing approach for this without using Spring annotations?	pass→pass	9,418	11,171	+19%	1	1	0%	2,081	2,651	+27%	0	0	—
case-20 Write a REST controller in Java 17 for managing product inventory, with GET /products/{id} endpoint returning a Product record, using standard Spring Boot annotations.	pass→pass	7,332	6,019	-18%	1	1	0%	1,531	1,449	-5%	0	0	—
case-06 I am designing a Kotlin configuration builder where users define nested infrastructure nodes. I want to prevent outer builder functions from being called inside nested inner builder blocks. How do I restrict scope access in a Kotlin DSL?	pass→pass	8,577	8,257	-4%	1	1	0%	1,513	1,833	+21%	0	0	—
case-07 I am creating a text input field component in Jetpack Compose using Kotlin. I want the caller to manage the text state while maintaining previewability and testability. How should state management be structured?	pass→pass	14,203	13,550	-5%	1	1	0%	2,822	2,756	-2%	0	0	—
case-08 In a Kotlin Multiplatform project shared between Android and iOS, I need to get the platform-specific device model string in shared code. What Kotlin mechanism should I use to declare the common interface and supply platform implementations?	pass→pass	7,828	8,379	+7%	1	1	0%	1,571	1,530	-3%	0	0	—
case-09 I have a long-running CPU-bound loop inside a Kotlin coroutine that processes a large collection. Currently, cancelling the Job does not stop the loop immediately. How do I make this loop responsive to coroutine cancellation?	pass→pass	12,786	8,811	-31%	1	1	0%	2,143	1,851	-14%	0	0	—
case-10 I am collecting items from a Kotlin Flow stream and want to handle errors emitted upstream by logging them and emitting a fallback value. Where should I put the error handling code?	pass→pass	8,099	7,503	-7%	1	1	0%	1,417	1,493	+5%	0	0	—
case-11 I am writing a Kotlin suspend function loadUserData() that performs disk reading and JSON parsing. Should I require callers to switch to Dispatchers.IO before calling loadUserData(), or handle it inside?	pass→pass	10,524	8,578	-18%	1	1	0%	1,576	1,746	+11%	0	0	—
case-12 In a Jetpack Compose UI, I have a LazyColumn that needs to show a scroll to top button when the user scrolls past item index 5. Recomputing listState.firstVisibleItemIndex > 5 directly in the composable triggers excessive recompositions during scrolling. How should this state be calculated?	pass→pass	8,495	6,242	-27%	1	1	0%	1,681	1,296	-23%	0	0	—
case-13 I want to write a Kotlin generic JSON deserializer helper fun parseJson(json: String) that returns an instance of type T without requiring callers to manually pass Class<T> as an explicit parameter. How can I achieve this?	fail→pass	11,220	7,702	-31%	1	1	0%	2,172	1,647	-24%	0	0	—
case-14 I need to implement a Kotlin class DecoratedList<T> that wraps an internal List<T> and logs every call to get(), while inheriting all other List<T> methods without manually delegating each method call. How can I do this concisely?	pass→pass	8,901	5,079	-43%	1	1	0%	1,310	1,163	-11%	0	0	—
case-21 Write an iOS networking function in Swift 5 using native async/await and URLSession to fetch user details from an API endpoint, updating a SwiftUI view state.	pass→pass	11,672	12,856	+10%	1	1	0%	2,632	2,641	+0%	0	0	—
case-15 I am refactoring a Kotlin codebase that has a StringUtils object containing static methods like fun capitalizeWords(str: String): String. What is the idiomatic Kotlin approach for adding domain utility operations to existing types?	pass→pass	10,602	7,626	-28%	1	1	0%	2,063	1,469	-29%	0	0	—
case-16 I have a Kotlin Flow producing fast sensor telemetry updates every 10ms, but the UI subscriber can only process and render updates every 100ms. I want to drop intermediate updates so the UI always renders only the latest update without blocking the producer. Which Flow operator should I use?	pass→pass	8,486	8,130	-4%	1	1	0%	1,538	1,602	+4%	0	0	—
case-17 I am modeling network response states in Kotlin (Success, Error, Loading). I want the compiler to enforce exhaustive checking when matching on these states without needing an else branch in when expressions. How should I define the state hierarchy?	pass→pass	9,366	9,057	-3%	1	1	0%	1,726	1,644	-5%	0	0	—
case-18 I need to make an asynchronous HTTP GET request in Kotlin to fetch JSON weather data from a remote endpoint and parse it directly into a data class. What is the idiomatic modern Kotlin HTTP client approach?	pass→pass	10,983	10,753	-2%	1	1	0%	2,429	2,590	+7%	0	0	—
case-19 I am designing a task distribution system in Kotlin where work items generated in one background worker coroutine must be sent to multiple worker coroutines so that each task item is processed by exactly one worker. Should I use a cold Flow or a Channel?	pass→pass	9,608	10,447	+9%	1	1	0%	1,731	1,830	+6%	0	0	—
case-22 In a Java 8 legacy application, submit 5 concurrent task Callables to a thread pool and gather their Future results using standard java.util.concurrent classes.	pass→pass	13,238	8,120	-39%	1	1	0%	2,376	1,894	-20%	0	0	—

These cases were also screened by the skill’s intent / safety pass.See the Trust review ↗Reproduce this benchmark in Colab ↗

How this skill was measured

DecimalAI ran this skill against gemini-3.6-flash twice over the same eval suite — once with the skill loaded and once without — and compared the two runs case by case. 22 cases were attempted. The headline lift of +5 percentage points is the difference between those two pass rates over the 22 comparable cases.

Model measured: gemini-3.6-flash
Graded by: gemini-3.6-flash
Grading method: judged
Verification: verified
Pass rate without the skill: 90.9%
Pass rate with the skill: 95.5%
Cases attempted: 22
Cases counted toward lift: 22
Cases that regressed: 0
Skill version measured: v1
Run completed: 8/4/2026, 17:21 UTC

Measured example — same prompt, with vs. without the skill · from the benchmark run · case case-13

Prompt

I want to write a Kotlin generic JSON deserializer helper fun parseJson(json: String) that returns an instance of type T without requiring callers to manually pass Class<T> as an explicit parameter. How can I achieve this?

Without the skill loaded, the model failed this case. With it loaded, the same prompt on the same model passed. This is one improved case from the latest verified run; every case, including any that regressed, is in the table above.

Show both answers

SkillScore blends 4 signals1 of 4 complete

BenchmarkPass rate WITH skill on a verified run95

Live evalNeeds ≥10 evaluated traces in 30 days

AI ratingNeeds ≥10 rated traces

AdoptionNeeds ≥10 serves across ≥2 orgs in 30 days

Efficiency · separate axis (at equal correctness)+0% turns-3% tokens

Shown for transparency; not credited unless a verified run shows no correctness regression.

Backed by 1 of 4 signals — each added signal makes the score more robust.

Verified on gemini-3.6-flash · re-tested 54 days ago

Other measured skills in the registry, with their headline benchmark lift.