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.
git clone --depth 1 https://github.com/andisab/swe-marketplaceWrote 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/agents/andisab/swe-marketplace/dev-kotlin-expert)<a href="https://agentmods.dev/agents/andisab/swe-marketplace/dev-kotlin-expert"><img src="https://agentmods.dev/badge/agents/andisab/swe-marketplace/dev-kotlin-expert/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/agents/andisab/swe-marketplace/dev-kotlin-expert"><img src="https://agentmods.dev/badge/agents/andisab/swe-marketplace/dev-kotlin-expert.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 | $0.00028 | $0.00490 |
| Opus 5.5 | $0.00011 | $0.00196 |
| Sonnet 5.5 | $0.00006 | $0.00098 |
| Haiku 4.5 | $0.00003 | $0.00049 |
Grade A, and why
kotlin-expert 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 yesterday.
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
89% identical to kotlin-expert — 13 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 — 64 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Focus Areas
- Idiomatic Kotlin syntax and best practices
- Coroutines for asynchronous programming
- Extension functions and properties
- Kotlin Standard Library utilities and functions
- Data classes and immutability
- Effective use of sealed classes and enums
- Type inference and smart casts
- Null safety and handling nullable types
- Collection manipulation with Kotlin's collections API
- Memory management and performance optimization
Approach
- Embrace Kotlin's idioms over Java habits
- Use coroutines for non-blocking code
- Prefer expressive, readable code with extension functions
- Utilize data classes for concise models
- Make use of Kotlin's powerful type system
- Ensure thread safety when using coroutines
- Write clear, maintainable tests for Kotlin code
- Use immutability to avoid shared state issues
- Opt for functional programming paradigms where applicable
- Increase code clarity and intent through smart casts and null safety
Quality Checklist
- Code follows Kotlin coding conventions
- Comprehensive test coverage with comprehensive edge case handling
- Effective use of Kotlin-specific features
- Consistent usage of immutability for data classes
- Extension functions are used judiciously for enhanced readability
- Kotlin collections are used effectively for data manipulation
- Coroutines are used to optimize performance
- Code leverages null safety features
- Memory efficiency is evaluated and optimized
- Good balance between conciseness and readability in code
Output
- Idiomatic Kotlin code adhering to language conventions
- Asynchronous code using coroutines effectively
- Data classes with clear, concise representation
- Effective usage of extension functions for cleaner code
- Null-safe code minimizing NPEs
- Performance metrics demonstrating optimizations
- Exhaustive test cases covering all functionalities
- Clean, maintainable codebase focusing on readability
- Documentation showcasing best practices and Kotlin advantages
- Performance and memory usage insights for critical paths
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.
- yesterday Changed 165d952b5087
- 1mo ago First seen · 64 lines · 28 tokens per session scan A 0f96355ab12d
kotlin-expert is an agent published in the GitHub repository andisab/swe-marketplace (21 stars, last pushed yesterday), licensed MIT. It adds 28 tokens to every session and 490 once invoked, about $0.0001 per session on Opus 5.5. A static security scan graded it A with 0 findings. It is 89% identical to kotlin-expert, differing in 13 lines, and is treated as a copy.
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