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 cxcscmu/SkillLearnBench --skill python-scala-collectionsgit clone --depth 1 https://github.com/cxcscmu/SkillLearnBenchWrote 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/cxcscmu/skilllearnbench/python-scala-collections)<a href="https://agentmods.dev/skills/cxcscmu/skilllearnbench/python-scala-collections"><img src="https://agentmods.dev/badge/skills/cxcscmu/skilllearnbench/python-scala-collections.svg" alt="Measured on agentmods" 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 | $0.00018 | $0.00284 |
| Opus 5 | $0.00009 | $0.00142 |
| Sonnet 5 | $0.00004 | $0.00057 |
| Haiku 4.5 | $0.00002 | $0.00028 |
Grade A, and why
python-scala-collections 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 3d 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
Python to Scala Collections
Type Mappings
| Python | Scala |
|---|---|
list[T] |
List[T] or mutable.ListBuffer[T] |
dict[K, V] |
Map[K, V] or mutable.Map[K, V] |
tuple[T, ...] |
(T, ...) or Vector[T] |
set[T] |
Set[T] |
Sequence[T] |
Seq[T] |
Iterable[T] |
Iterable[T] |
Iterator[T] |
Iterator[T] |
Mutable Collections
import scala.collection.mutable
// Python: list with append -> mutable.ListBuffer
val buf = mutable.ListBuffer.empty[Token]
buf += token
// Python: dict -> mutable.Map
val reg = mutable.Map.empty[String, TokenContainer[T]]
reg(key) = container
Collection Operations
// Python: [f(x) for x in xs] -> xs.map(f)
// Python: [x for x in xs if p(x)] -> xs.filter(p)
// Python: enumerate(xs) -> xs.zipWithIndex
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.
- 3d ago First seen · 38 lines · 18 tokens per session scan A 3e83842e821a
python-scala-collections is a skill published in the GitHub repository cxcscmu/SkillLearnBench (83 stars, last pushed 1mo ago), licensed MIT. It adds 18 tokens to every session and 284 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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