Agent skill

Jspecify Skill

by sivaprasadreddy in sivaprasadreddy/sivalabs-agent-skills

A skill your agent uses when asked to perform any of the following actions in a Java project: - To add jspecify support - To prevent NullPointerExceptions - To better handle Nullability This skill…

MITAuto-check passedBackend & APIs

Install Jspecify Skill

skills CLI

$ npx skills add sivaprasadreddy/sivalabs-agent-skills --skill jspecify-skill -a claude-code

Project install by default; add -g for ~/.claude/skills/.

GitHub CLI

$ gh skill install sivaprasadreddy/sivalabs-agent-skills jspecify-skill --agent claude-code

Project scope by default; add --scope user for a personal install. Needs GitHub CLI 2.90.0 or later (public preview).

Manual copy

$ git clone --depth 1 https://github.com/sivaprasadreddy/sivalabs-agent-skills.git skills-src && mkdir -p .claude/skills && cp -r skills-src/skills/jspecify .claude/skills/jspecify-skill && rm -rf skills-src

Use ~/.claude/skills/ instead of .claude/skills for a personal install. The folder must contain SKILL.md.

Claude Code skills documentation · loads skills from .claude/skills/

Paste into Claude Code

Install the "jspecify-skill" agent skill from https://github.com/sivaprasadreddy/sivalabs-agent-skills/tree/main/skills/jspecify into .claude/skills/jspecify-skill/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "jspecify-skill", then confirm the skill loads.

Claude Code copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

$skill-installer

$skill-installer install https://github.com/sivaprasadreddy/sivalabs-agent-skills/tree/main/skills/jspecify

Type this inside Codex. $skill-installer <name> installs a curated skill from openai/skills. The installer writes to $CODEX_HOME/skills (default ~/.codex/skills). Restart Codex if the skill does not show up.

skills CLI

$ npx skills add sivaprasadreddy/sivalabs-agent-skills --skill jspecify-skill -a codex

Project install goes to .agents/skills/; add -g for ~/.codex/skills/.

GitHub CLI

$ gh skill install sivaprasadreddy/sivalabs-agent-skills jspecify-skill --agent codex

Project scope by default (.agents/skills/); add --scope user for a personal install.

Manual copy

$ git clone --depth 1 https://github.com/sivaprasadreddy/sivalabs-agent-skills.git skills-src && mkdir -p .agents/skills && cp -r skills-src/skills/jspecify .agents/skills/jspecify-skill && rm -rf skills-src

Use ~/.agents/skills/ instead of .agents/skills for a personal install.

Codex skills documentation · loads skills from .agents/skills/

Paste into Codex

Install the "jspecify-skill" agent skill from https://github.com/sivaprasadreddy/sivalabs-agent-skills/tree/main/skills/jspecify into .agents/skills/jspecify-skill/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "jspecify-skill", then confirm the skill loads.

Codex copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

skills CLI

$ npx skills add sivaprasadreddy/sivalabs-agent-skills --skill jspecify-skill -a cursor

Project install goes to .agents/skills/; add -g for ~/.cursor/skills/.

GitHub CLI

$ gh skill install sivaprasadreddy/sivalabs-agent-skills jspecify-skill --agent cursor

Project scope by default (.agents/skills/); add --scope user for a personal install.

Manual copy

$ git clone --depth 1 https://github.com/sivaprasadreddy/sivalabs-agent-skills.git skills-src && mkdir -p .cursor/skills && cp -r skills-src/skills/jspecify .cursor/skills/jspecify-skill && rm -rf skills-src

Use ~/.cursor/skills/ instead of .cursor/skills for a personal install.

Cursor skills documentation · loads skills from .cursor/skills/, .agents/skills/, .claude/skills/, .codex/skills/

Paste into Cursor

Install the "jspecify-skill" agent skill from https://github.com/sivaprasadreddy/sivalabs-agent-skills/tree/main/skills/jspecify into .cursor/skills/jspecify-skill/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "jspecify-skill", then confirm the skill loads.

Cursor copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

gemini skills install

$ gemini skills install https://github.com/sivaprasadreddy/sivalabs-agent-skills.git --path skills/jspecify

--scope user (default) or --scope workspace; --path is the subfolder of the repo that holds the skill; --consent skips the security confirmation prompt.

skills CLI

$ npx skills add sivaprasadreddy/sivalabs-agent-skills --skill jspecify-skill -a gemini-cli

Project install goes to .agents/skills/; add -g for ~/.gemini/skills/.

GitHub CLI

$ gh skill install sivaprasadreddy/sivalabs-agent-skills jspecify-skill --agent gemini-cli

Project scope by default (.agents/skills/); add --scope user for a personal install.

Manual copy

$ git clone --depth 1 https://github.com/sivaprasadreddy/sivalabs-agent-skills.git skills-src && mkdir -p .gemini/skills && cp -r skills-src/skills/jspecify .gemini/skills/jspecify-skill && rm -rf skills-src

Use ~/.gemini/skills/ instead of .gemini/skills for a personal install, then run /skills reload.

Gemini CLI skills documentation · loads skills from .gemini/skills/, .agents/skills/

Paste into Gemini CLI

Install the "jspecify-skill" agent skill from https://github.com/sivaprasadreddy/sivalabs-agent-skills/tree/main/skills/jspecify into .gemini/skills/jspecify-skill/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "jspecify-skill", then confirm the skill loads.

Gemini CLI copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

GitHub CLI

$ gh skill install sivaprasadreddy/sivalabs-agent-skills jspecify-skill

Installs for Copilot at project scope by default; add --scope user for a personal install. Preview a skill first with gh skill preview. Needs GitHub CLI 2.90.0 or later (public preview).

skills CLI

$ npx skills add sivaprasadreddy/sivalabs-agent-skills --skill jspecify-skill -a github-copilot

Project install goes to .agents/skills/; add -g for ~/.copilot/skills/.

Manual copy

$ git clone --depth 1 https://github.com/sivaprasadreddy/sivalabs-agent-skills.git skills-src && mkdir -p .github/skills && cp -r skills-src/skills/jspecify .github/skills/jspecify-skill && rm -rf skills-src

Use ~/.copilot/skills/ instead of .github/skills for a personal install. Commit .github/skills so cloud agent and code review can use it.

GitHub Copilot skills documentation · loads skills from .github/skills/, .claude/skills/, .agents/skills/

Paste into GitHub Copilot

Install the "jspecify-skill" agent skill from https://github.com/sivaprasadreddy/sivalabs-agent-skills/tree/main/skills/jspecify into .github/skills/jspecify-skill/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "jspecify-skill", then confirm the skill loads.

GitHub Copilot copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

skills CLI

$ npx skills add sivaprasadreddy/sivalabs-agent-skills --skill jspecify-skill -a opencode

OpenCode documents no install command of its own. Project install goes to .agents/skills/; add -g for ~/.config/opencode/skills/.

GitHub CLI

$ gh skill install sivaprasadreddy/sivalabs-agent-skills jspecify-skill --agent opencode

Project scope by default (.agents/skills/); add --scope user for a personal install.

Manual copy

$ git clone --depth 1 https://github.com/sivaprasadreddy/sivalabs-agent-skills.git skills-src && mkdir -p .opencode/skills && cp -r skills-src/skills/jspecify .opencode/skills/jspecify-skill && rm -rf skills-src

Use ~/.config/opencode/skills/ instead of .opencode/skills for a personal install.

OpenCode skills documentation · loads skills from .opencode/skills/, .claude/skills/, .agents/skills/

Paste into OpenCode

Install the "jspecify-skill" agent skill from https://github.com/sivaprasadreddy/sivalabs-agent-skills/tree/main/skills/jspecify into .opencode/skills/jspecify-skill/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "jspecify-skill", then confirm the skill loads.

OpenCode copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

Facts

Skill name: jspecify-skill
GitHub stars: 188
Token cost: ~1.2k tokens
SKILL.md length: 311 words
Files: 5 (incl. scripts, references)
Skills in repo: 6
Repo updated: Oct 5, 2026
First seen: Oct 7, 2026
Licence: MIT

At a glance

A skill your agent uses when asked to perform any of the following actions in a Java project: - To add jspecify support - To prevent NullPointerExceptions - To better handle Nullability This skill…

Configure Maven
SKILL.md covers Add jSpecify support in Maven…, Add jSpecify support in Gradle…, Add @NullMarked to… and Verify jSpecify support, plus 3 more sections
Runs Python scripts from its folder
Gradle build to automatically use jspecify for checking Nullability issues

What it does

Jspecify Skill is an agent skill from sivaprasadreddy/sivalabs-agent-skills. Use this skill when asked to perform any of the following actions in a Java project: - To add jspecify support - To prevent NullPointerExceptions - To better handle Nullability This skill will add jspecify dependency, configure Maven or Gradle build to automatically use jspecify for checking Nullability issues.

Its SKILL.md is about 1.2k tokens, which your agent loads only when the skill is triggered. The skill folder holds 6 other files, including scripts and reference files (for example `references/annotation-migration.md`, `references/incremental-adoption.md` and `references/kotlin-interop.md`).

It sits in Backend & APIs. It works with Java and Gradle. The repository describes itself as: Spring Boot skills for AI coding agents. The licence is MIT.

When your agent uses it

Configure Maven
Gradle build to automatically use jspecify for checking Nullability issues

Example prompts

“/jspecify-skill”

Requirements

Python 3

What it can do on your machine

Read from SKILL.md and the folder at commit e9f9861. It shows what the files ask for, not the result of running them.

Tool permissions
Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.
From allowed-tools in the SKILL.md frontmatter.
Runs code
Ships 1 file in scripts/ (Python), which the agent can run.
From the folder's file list and the shell code blocks in SKILL.md.
Network
No URLs in SKILL.md.
From URLs in SKILL.md, links to its own repository left out.
Credentials
Names no API keys, tokens, secrets or passwords.
From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.

Context cost

Jspecify Skill loads about 1.2k tokens when it runs, and up to ~6.7k if it reads all its reference files. Until then it costs about 84 tokens; SKILL.md has 311 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it: ~84
When it runs · the whole SKILL.md, loaded when a task matches: ~1.2k
With references · SKILL.md plus every file in references/, read only if the agent opens them: ~6.7k

Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.

Safety

Auto-check passed

The automated check found no risky patterns in SKILL.md.

Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); the scripts in this folder are not scanned.

SKILL.md

The full file from sivaprasadreddy/sivalabs-agent-skills at commit e9f9861, republished under its MIT licence (© sivaprasadreddy). 311 words, ~1,177 tokens.

Download SKILL.mdSave it as .claude/skills/jspecify-skill/SKILL.md (or your agent's skills folder). This skill also uses 4 other files; get the full folder from GitHub.

name: jspecify-skill
description: Use this skill when asked to perform any of the following actions in a Java project: - To add jspecify support - To prevent NullPointerExceptions - To better handle Nullability This skill will add jspecify dependency, configure Maven or Gradle build to automatically use jspecify for checking Nullability issues.

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.

xml

<dependencies>
    <dependency>
        <groupId>org.jspecify</groupId>
        <artifactId>jspecify</artifactId>
        <version>1.0.0</version>
    </dependency>
</dependencies>

<build>
    <plugins>
        <plugin>
            <groupId>am.ik.maven</groupId>
            <artifactId>nullability-maven-plugin</artifactId>
            <version>0.4.2</version>
            <extensions>true</extensions>
            <configuration>
                <checking>tests</checking>
                <outputDirectory>${project.basedir}/src/main/java</outputDirectory>
                <testOutputDirectory>${project.basedir}/src/test/java</testOutputDirectory>
            </configuration>
            <executions>
                <execution>
                    <goals>
                        <goal>configure</goal>
                        <goal>generate-package-info</goal>
                    </goals>
                </execution>
            </executions>
        </plugin>
    </plugins>
</build>

Add jSpecify support in Gradle projects

If you are using Gradle, then add the jspecify dependency. In build.gradle or build.gradle.kts, update or add the following jspecify configuration.

groovy

plugins {
    id("net.ltgt.errorprone") version "5.1.0"
    id("net.ltgt.nullaway") version "3.1.0"
}

tasks.withType(JavaCompile).configureEach {
    options.errorprone {
        disableAllChecks = true // Other error prone checks are disabled
        error("RequireExplicitNullMarking") // Require @NullMarked or @NullUnmarked on everything
        nullaway {
            error()
        }
    }
    // Keep a JDK 25 baseline
    options.release = 25
}

nullaway {
    onlyNullMarked = true
    jspecifyMode = true
}

dependencies {
    implementation("org.jspecify:jspecify:1.0.0")
    errorprone("com.google.errorprone:error_prone_core:2.50.0")
    errorprone("com.uber.nullaway:nullaway:0.13.7")
}

Add @NullMarked to package-info.java files

In every java package under the application main source code (src/main/java), create package-info.java if not exists already, and add the @NullMarked annotation as follows:

java

@org.jspecify.annotations.NullMarked
package com.mycompnay.myproject;

If package-info.java file already exists, update the file to add @org.jspecify.annotations.NullMarked annotation. DO NOT REMOVE ANY OTHER EXISTING CODE IN package-info.java FILE.

Verify jSpecify support

If python is installed, after adding the jSpecify support, run scripts/verify_nullmarked.py to check if all non-empty packages has package-info.java file or not.

Migrating an existing codebase from other annotation libraries

If the project already uses another nullability annotation library (JSR-305 / javax, Jakarta, JetBrains, Spring, Android, FindBugs/SpotBugs, Checker Framework, or Eclipse JDT), migrate those annotations to JSpecify before adding @NullMarked. The OpenRewrite MigrateToJSpecify recipe automates the common cases (javax, Jakarta, JetBrains, Micrometer, Micronaut); the rest are a short manual mapping. See references/annotation-migration.md.

Incremental adoption for large codebases

Flipping every package to @NullMarked at once is impractical on a large or legacy codebase. @NullUnmarked lets you enforce NullAway on a growing perimeter while the rest stays untouched. Because the build above enables OnlyNullMarked mode, packages without @NullMarked are simply ignored — so adoption is driven purely by adding markers, one package at a time. Strategies, progress tracking, common NullAway errors, and redundant null-guard removal are in references/incremental-adoption.md.

Kotlin interop (optional)

If the project also has Kotlin sources, the Kotlin compiler (K2) reads JSpecify annotations on Java APIs and surfaces accurate nullability instead of platform types. See references/kotlin-interop.md.

Files

SKILL.md and 4 other files (scripts, references) in skills/jspecify of sivaprasadreddy/sivalabs-agent-skills.

SKILL.md
references/annotation-migration.md
references/incremental-adoption.md
references/kotlin-interop.md
scripts/verify_nullmarked.py

Open the folder on GitHubat commit e9f9861

Compare with similar skills

Jspecify Skill next to the 5 skills that share the most tags, products or categories with it. Stars are the repository's; “used in” counts other GitHub owners with a copy.

Jspecify Skill compared with similar skills
Skill	Stars	Used in	Tokens	Auto-check	Licence	Repo updated
Jspecify Skill this skillsivaprasadreddy/sivalabs-agent-skills	188	—	~1.2k	Automated safety check: Pass	MIT	4 days ago
Tiger Brokers Java SDKqusong0627/QuantMind	1.7k	—	~1.2k	Automated safety check: Pass	Apache-2.0	today
New Extensionyontrack/yontrack	102	—	~1k	Automated safety check: Pass	MIT	today
Starter Domain Revieweraxelixlabs/axelix	148	—	~3.3k	Automated safety check: Pass	LGPL-3.0	yesterday
Codingmicronaut-projects/micronaut-openapi	114	—	~2.6k	Automated safety check: Pass	Apache-2.0	yesterday
Java ArchitectJeffallan/claude-skills	12k	—	~1.5k	Automated safety check: Pass	MIT	6 days ago

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Questions about Jspecify Skill

What does Jspecify Skill do?

A skill your agent uses when asked to perform any of the following actions in a Java project: - To add jspecify support - To prevent NullPointerExceptions - To better handle Nullability This skill…. Jspecify Skill is an agent skill from sivaprasadreddy/sivalabs-agent-skills. Use this skill when asked to perform any of the following actions in a Java project: - To add jspecify support - To prevent NullPointerExceptions - To better handle Nullability This skill will add jspecify dependency, configure Maven or Gradle build to automatically use jspecify for checking Nullability issues.

When should I use Jspecify Skill?

Jspecify Skill fits situations like: configure Maven; gradle build to automatically use jspecify for checking Nullability issues.

How do I install Jspecify Skill in Claude Code?

Run `npx skills add sivaprasadreddy/sivalabs-agent-skills --skill jspecify-skill -a claude-code`. Or copy the skill folder (skills/jspecify in sivaprasadreddy/sivalabs-agent-skills) into .claude/skills/jspecify-skill in your project. Claude Code loads it when a task matches its description.

How do I install Jspecify Skill in Codex?

Run `npx skills add sivaprasadreddy/sivalabs-agent-skills --skill jspecify-skill -a codex`. Or copy the skill folder (skills/jspecify in sivaprasadreddy/sivalabs-agent-skills) into .agents/skills/jspecify-skill in your project. Codex loads it when a task matches its description.

Can I use Jspecify Skill in Cursor, Gemini CLI or GitHub Copilot?

Cursor, Gemini CLI, GitHub Copilot and OpenCode also load SKILL.md folders. With the skills CLI, run `npx skills add sivaprasadreddy/sivalabs-agent-skills --skill jspecify-skill -a cursor` (or -a gemini-cli, github-copilot or opencode for the others). To copy it by hand, put the folder in .cursor/skills/jspecify-skill, .gemini/skills/jspecify-skill, .github/skills/jspecify-skill and .opencode/skills/jspecify-skill in your project.

What does Jspecify Skill need to run?

Going by SKILL.md and its folder, Jspecify Skill needs Python for the scripts in its folder. Our summary lists: Python 3.

Does Jspecify Skill access the network?

SKILL.md contains no URLs. Any network use would come from the scripts or tools the agent runs. This is read from the text; nothing was executed.

Is Jspecify Skill safe to install?

Our automated static check of SKILL.md found no risky patterns, such as piping downloads into a shell, reading credential files or hidden Unicode. It is not a guarantee. The check reads SKILL.md only: the scripts in the folder are not scanned, so read them before running anything.

What licence does Jspecify Skill use?

Jspecify Skill is published under the MIT licence (the repository's licence). It allows redistribution, so the full SKILL.md is shown on this page.

How many tokens does Jspecify Skill use?

About 1.2k tokens (SKILL.md is roughly 4.7k characters). Agents keep only the skill's name and description in context until a task matches; then they load SKILL.md in full. Its references folder adds about 5.5k tokens, read only when the agent opens those files.

What are the alternatives to Jspecify Skill?

Skills that share tags, products or a category with Jspecify Skill: Tiger Brokers Java SDK (qusong0627/QuantMind, 1.7k stars), New Extension (yontrack/yontrack, 102 stars), Starter Domain Reviewer (axelixlabs/axelix, 148 stars) and Coding (micronaut-projects/micronaut-openapi, 114 stars). The comparison table on this page puts their stars, adoption, token cost, safety result and licence side by side.

Who maintains Jspecify Skill?

sivaprasadreddy (a GitHub user) maintains it in sivaprasadreddy/sivalabs-agent-skills, which has 188 GitHub stars. The repository holds 6 skills in this directory. The repository was last updated on October 5, 2026.

Source: sivaprasadreddy/sivalabs-agent-skills on GitHub. Facts on this page come from the repository at the commit we read; the author's words are quoted as theirs.

Jspecify Skill

Install Jspecify Skill

Facts

At a glance

What it does

When your agent uses it

Example prompts

Requirements

What it can do on your machine

Tool permissions

Runs code

Network

Credentials

Context cost

Safety

SKILL.md

Add jSpecify support in Maven projects

Add jSpecify support in Gradle projects

Add @NullMarked to package-info.java files

Verify jSpecify support

Migrating an existing codebase from other annotation libraries

Incremental adoption for large codebases

Kotlin interop (optional)

Files

Compare with similar skills

Similar skills

Tiger Brokers Java SDK

New Extension

Starter Domain Reviewer

Coding

Java Architect

Spring Mvc To Boot Migrator

More from sivaprasadreddy/sivalabs-agent-skills

Apply Renovate PRs

Java Code Review

Progen

Spring Modulith Verifier

Spring Boot Skill

Questions about Jspecify Skill

Install Jspecify Skill

Facts

At a glance

What it does

When your agent uses it

Example prompts

Requirements

What it can do on your machine

Tool permissions

Runs code

Network

Credentials

Context cost

Safety

SKILL.md

Add jSpecify support in Maven projects

Add jSpecify support in Gradle projects

Add @NullMarked to package-info.java files

Verify jSpecify support

Migrating an existing codebase from other annotation libraries

Incremental adoption for large codebases

Kotlin interop (optional)

Files

Compare with similar skills

Similar skills

More from sivaprasadreddy/sivalabs-agent-skills

Related

Questions about Jspecify Skill