JSpecify

by sivaprasadreddy

JSpecify is a Quality skill for Claude Code, published by sivaprasadreddy in sivalabs-agent-skills.

178 stars41 forkson sivaprasadreddy/sivalabs-agent-skillsAdded 2026/09/07+2% in starsRepository updated 2026/09/03

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agent-skillsaiai-agentsclaude-codeclaude-skillsjavaspring-bootspring-modulith

Install in seconds

Install JSpecify

Copy JSpecify into your Claude Code skills folder. Run the command in your terminal, or review the source on GitHub before installing.

terminal

npx degit https://github.com/sivaprasadreddy/sivalabs-agent-skills/tree/main/skills/jspecify ~/.claude/skills/jspecify

Requires Node.js. Downloads this skill only — not the rest of the repository — into your Claude Code skills folder.

Without Node.js

git clone https://github.com/sivaprasadreddy/sivalabs-agent-skills.git

Clones the whole repository, then copy the skill’s own directory into your skills folder yourself.

In this catalog

Source file: skills/jspecify/SKILL.md in sivaprasadreddy/sivalabs-agent-skills
Installs to: ~/.claude/skills/jspecify
Collection: One of 7 skills cataloged from this repository
Category: Quality — 1817 skills

What JSpecify does

JSpecify adds nullability annotations and build setup for Java projects. Use it to enable NullMarked/NullUnmarked, reduce NullPointerExceptions, and verify package coverage with Maven or Gradle.

JSpecify is cataloged under Quality on DirSkills. JSpecify comes from a repository tagged agent-skills, ai, ai-agents, claude-code and claude-skills.

Documentation

README

Excerpt

Jspecify provides a set of annotations to explicitly declare the nullness expectations of the Java code.

Add jSpecify support in Maven projects

If you are using Maven, then add the jspecify dependency in pom.xml. In pom.xml, update or add the nullability-maven-plugin, to include the following configuration.

This is the opening of the README. Read the full README on GitHub.

Frequently asked about JSpecify

What else does sivaprasadreddy publish alongside JSpecify?
JSpecify is one of 7 skills that DirSkills catalogs from sivaprasadreddy/sivalabs-agent-skills, the repository it ships in. Its siblings there include Apply Renovate PRs Locally, Java Code Review and Pair Programming. Each one is a separate skill with its own page in this directory, installs the same way JSpecify does, and is maintained by sivaprasadreddy in that same repository. The rest of the collection is listed on the sivaprasadreddy/sivalabs-agent-skills page.
How does JSpecify compare to other Quality skills?
JSpecify ranks #1685 by stars among the 1817 Quality skills in this catalog. The most-starred ones next to it are Benchmark, Benchmark Optimization Loop and API Design Patterns. DirSkills ranks by the star count of the repository each skill ships in, so that order reflects how popular those repositories are rather than any review of JSpecify against them. Open each page to compare what they document and how they install.