125-java-concurrency

Use when you need to apply Java concurrency best practices — including thread safety fundamentals, ExecutorService thread pool management, concurrent design patterns like Producer-Consumer, asynchronous programming with CompletableFuture, immutability and safe publication, deadlock avoidance, virtual threads, structured concurrency, scoped values, backpressure, cancellation discipline, and observability for concurrent systems. This should trigger for requests such as Review Java code for concurrency. Part of cursor-rules-java project

Quality

—

Does it follow best practices?

Impact

—

No eval scenarios have been run

Securityby

Passed

No known issues

Quality

Content

70%

Reviews the quality of instructions and guidance provided to agents. Good implementation is clear, handles edge cases, and produces reliable results.

A well-structured overview with a clear, validated workflow and clean one-level-deep progressive disclosure into a real reference file. Its weaknesses are mild redundancy in the constraints section and the fact that executable code examples live only in the reference rather than the body.

Suggestions

Remove the duplicated 'compilation failure is a blocking condition' phrasing — keep it once, either in the intro or the SAFETY bullet, not both.

Add one small inline good/bad code snippet (e.g., a ReentrantLock-with-tryLock-timeout example) in the body so the skill is immediately actionable without opening the reference.

Dimension	Reasoning	Score
Conciseness	The body is mostly efficient — a concise topic index with no basic-concept padding — but the compile/verify constraint is stated redundantly ('If compilation fails, stop immediately — compilation failure is a blocking condition' appears in both the intro paragraph and the SAFETY bullet), which is unnecessary repetition that could be tightened.	2 / 3
Actionability	It gives concrete commands ('./mvnw compile', 'mvn clean verify') and names specific APIs (Executors.newVirtualThreadPerTaskExecutor(), StructuredTaskScope), but the actual executable good/bad code patterns are deferred to the reference, so the body alone is incomplete rather than copy-paste ready.	2 / 3
Workflow Clarity	The four-step workflow is clearly sequenced (compile → read reference → apply → verify) with an explicit validation checkpoint ('stop immediately if compilation fails') and a verify-after step, matching the anchor for a clear sequence with explicit validation and an error-recovery feedback loop.	3 / 3
Progressive Disclosure	The body is a clear overview that signals a single one-level-deep reference (references/125-java-concurrency.md, which exists in the bundle) for detailed good/bad examples, with content appropriately split and easy navigation via the Reference section and workflow step 2.	3 / 3
	Total	10 / 12 Passed

Description

85%

Based on the skill's description, can an agent find and select it at the right time? Clear, specific descriptions lead to better discovery.

A strong, specific description with an explicit Use-when trigger and a clear niche. Its main weakness is trigger-term quality: it leans heavily on technical jargon and offers only one concrete example trigger phrase rather than a spread of natural user variations.

Suggestions

Add 2-3 natural trigger variations users would actually say (e.g., 'review my Java code for thread safety', 'fix a deadlock', 'make my Java code thread-safe') alongside the single 'Review Java code for concurrency' example.

Trim the long inline jargon list in the description and keep it as a high-level capability summary; move the exhaustive API enumeration into the body/reference where it already lives.

Dimension	Reasoning	Score
Specificity	The description enumerates many concrete capabilities — 'thread safety fundamentals', 'ExecutorService thread pool management', 'Producer-Consumer', 'CompletableFuture', 'virtual threads', 'structured concurrency' — matching the anchor that lists multiple specific concrete actions rather than vague language.	3 / 3
Completeness	It explicitly answers both 'what' (the long list of concurrency capabilities) and 'when' via an explicit 'Use when you need to apply...' clause plus 'This should trigger for requests such as Review Java code for concurrency', satisfying the anchor requiring both with explicit triggers.	3 / 3
Trigger Term Quality	It includes some natural trigger phrasings ('Java concurrency best practices', 'Review Java code for concurrency') but the bulk of the description is technical jargon (ScopedValue, structured concurrency, backpressure, cancellation discipline) with only one explicit example trigger phrase, so common variations are not well covered.	2 / 3
Distinctiveness Conflict Risk	The 'Java concurrency' niche is clear and specific with distinct triggers, making it unlikely to fire for unrelated skills; it is not a generic 'helps with code' description.	3 / 3
	Total	11 / 12 Passed

Validation

100%

Warnings & errors only

Checks the skill against the spec for correct structure and formatting. All validation checks must pass before discovery and implementation can be scored.

Validation — 16 / 16 Passed

Validation for skill structure

No warnings or errors.

Repository: jabrena/cursor-rules-java
Commit: 86eb63d

Reviewed: 4 days ago

Table of Contents

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