performance-smell-detection SKILL.md skillA
performance-smell-detection from decebals/claude-code-java is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add decebals/claude-code-java/performance-smell-detection@git:20260828.702770aPins git:20260828.702770a in mdr.lock. Pin the fingerprint instead.
- Audit grade
- A, 17 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- decebals/claude-code-java
- Path
skills/performance-smell-detection/SKILL.md- Versions recorded
- 1
- Latest version
- git:20260828.702770a, committed Aug 28, 2026
- Size
- 9,152 bytes
- Repository stars
- 768
- License
- MIT
Detect potential code-level performance smells in Java - streams, collections, boxing, regex, object creation. Provides awareness, not absolutes - always measure before optimizing. For JPA/database performance, use jpa-patterns instead.
Collected from public GitHub. Every version is saved exactly as it was and never changes. Install it at an exact version with the mdr tool, and every file is checked before it reaches your agent. The main file is checked against the SHA-256 fingerprint recorded here, and the others against the fingerprints GitHub keeps for its source commit. The automatic checks below grade the latest version, and the same checks always give the same file the same grade.
What the file says
# Performance Smell Detection Skill Identify **potential** code-level performance issues in Java code. ## Philosophy > "Premature optimization is the root of all evil" - Donald Knuth This skill helps you **notice** potential performance smells, not blindly "fix" them. Modern JVMs (Java 21/25) are highly optimized. Always: 1. **Measure first** - Use JMH, profilers, or production metrics 2. **Focus on hot paths** - 90% of time spent in 10% of code 3. **Consider readability** - Clear code often matters more than micro-optimizations ## When to Use - Reviewing performance-critical code paths - Investigating measured performance issues - Learning about Java performance patterns - Code review with performance awareness ## Scope **This skill:** Code-level performance (streams, collections, objects) **For database:** Use `jpa-patterns` skill (N+1, lazy loading, pagination) **For architecture:** Use `architecture-review` skill --- ## Quick Reference: Potential Smells | Smell | Severity | Context | |-------|----------|---------| | Regex compile in loop | 🔴 High | Always worth fixing | | String concat in loop | 🟡 Medium | Still valid in Java 21/25 | …
Read the whole file at its exact version.
How to install
mdr add decebals/claude-code-java/performance-smell-detection@sha256:a43c8936af13c473The line at the top of this page pins the label git:20260828.702770a, which is what most people want. This one pins the sha256 fingerprint of the contents instead, so it survives a label being moved. Either way the exact version is written to mdr.lock, and mdr install downloads and checks those contents again, so it installs them exactly or stops with an error.
[](https://markdownregistry.com/a/art_usk2qgwnw455h4y7)
4 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 1 version of this file, committed on Aug 28, 2026.
Audit of the latest version
- pass: Frontmatter block present
- pass: Frontmatter declares a name
- pass: Frontmatter declares a description
- pass: Size between 200 bytes and 200 KB (9152 bytes)
- pass: No zero-width or bidi control characters
- pass: No instruction hidden inside an HTML comment
- pass: No link to an exfiltration or paste host
- pass: No credential-shaped string
- pass: No instruction to send local credentials anywhere
- pass: No text hidden with inline styles
- pass: No prompt-injection phrasing
- pass: No curl or wget piped into a shell
- pass: No recursive delete of root, home or parent
- pass: No instruction to read or print local credentials
- pass: No base64 blob over 200 characters
- pass: No link to a raw IP address
- pass: No script tag
Source
decebals/claude-code-java · 768 stars · license MIT · pushed 2026-10-29 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_usk2qgwnw455h4y7 GET https://markdownregistry.com/api/v1/resolve?ref=decebals/claude-code-java/performance-smell-detection GET https://markdownregistry.com/api/v1/blob/a43c8936af13c473af74b81116fd55caf363546aed77ca9143d55c68dcbd2c67
Your AI assistant does the legwork. You hear about the deals worth your word. Hand yours the standing instructions at modelranch.com and it joins the network that reads files like this one.
Guides: the SKILL.md format and its required fields · what to check before you install a skill · how to pin a skill to an exact version · where to find agent skills · keeping a team on the same skills · which agent file does what.