Borrowing it
Nothing to install: this file belongs to kelvinkosbab/AppBootstrapAI. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/kelvinkosbab/AppBootstrapAI/main/.claude/skills/android-coroutines-pro/SKILL.mdgit clone --depth 1 https://github.com/kelvinkosbab/AppBootstrapAIWrote 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/kelvinkosbab/appbootstrapai/android-coroutines-pro)<a href="https://agentmods.dev/skills/kelvinkosbab/appbootstrapai/android-coroutines-pro"><img src="https://agentmods.dev/badge/skills/kelvinkosbab/appbootstrapai/android-coroutines-pro/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/kelvinkosbab/appbootstrapai/android-coroutines-pro"><img src="https://agentmods.dev/badge/skills/kelvinkosbab/appbootstrapai/android-coroutines-pro.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 | $0.00056 | $0.00991 |
| Opus 5 | $0.00028 | $0.00495 |
| Sonnet 5 | $0.00011 | $0.00198 |
| Haiku 4.5 | $0.00006 | $0.00099 |
Grade A, and why
android-coroutines-pro 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 9d 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 — 63 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Review Kotlin coroutines and Flow code for correctness. This is the deep-review companion to the always-on android-coroutines-best-practices.md rule — the rule steers while writing; this skill audits what was written. The Android sibling of swift-concurrency-pro. Report only genuine problems; don't nitpick.
Review process:
- Check scope and dispatcher discipline using
references/structured-concurrency.md— every coroutine's lifetime tied to a real lifecycle, dispatchers injected. - Check cancellation cooperation using
references/cancellation.md—CancellationExceptiondiscipline, CPU-loop checkpoints, cleanup paths. - Check exception propagation using
references/exceptions.md—launchvsasyncsemantics, supervisor boundaries, handler placement. - Check Flow construction and exposure using
references/flows.md— cold/hot boundaries,stateIn/shareInconfiguration, operator semantics. - Check the tests using
references/testing.md— virtual time, dispatcher substitution, Turbine discipline.
If doing a partial review, load only the relevant reference files.
Core Instructions
- Every coroutine needs an owner. The first question for any
launch/async: which scope, why that scope, and what cancels it. "Nothing cancels it" is a finding. - Cancellation is the invariant most code silently breaks. Trace every broad
catchand everyrunCatchingaround suspend code — swallowedCancellationExceptioncorrupts structured concurrency at a distance. - Distinguish bug classes from style. A swallowed cancellation or a deferred
asyncexception is correctness; a missingflowOnthat happens to run on the right dispatcher anyway is a latent risk; name which is which. - Flow exposure is API design. What a ViewModel/repository exposes (
StateFlowvsSharedFlowvs coldFlow, replay, sharing policy) determines consumer behavior — review it like a public interface. - Suspend under a non-suspending lock is a deadlock pattern (
synchronized/ReentrantLockaround suspension points) — always flag. - Assume Kotlin 2.x, kotlinx.coroutines 1.8+, Hilt for injection. Dispatchers arrive via qualified injection (
@IoDispatcher), never hardcoded at use sites.
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.
- 9d ago First seen · 63 lines · 56 tokens per session scan A df2ca4d76df4
android-coroutines-pro is a skill published in the GitHub repository kelvinkosbab/AppBootstrapAI (5 stars, last pushed 18d ago), licensed MIT. It adds 56 tokens to every session and 991 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 2026-08-31.
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