What are Cursor rules for Java?
A curated collection of Skills and Agents to be used in modern SDLC workflows for Java Enterprise development.
Thanks to our community members in Singapore, Chengdu, Hanoi, Copenhagen, and Quito. 👋👋👋
What's new in this release?
Rules support dropped in favor of Skills
It is a bit weird to explain that the project is named Cursor rules for Java, but one of the changes in this minor release is to drop support for Rules.
Why were Cursor rules dropped?
Until this release, the project maintained three very different deliverables: Rules, Skills, and Agents. Rules and Skills both guide model behaviour in broadly similar ways, but Rules were Cursor’s approach while Skills have recently become the standard, so consolidating on a single solution makes more sense. On the other hand, maintaining a single generator (skills-generator) made it possible to improve how skills are packaged, which was somewhat constrained when both rules-generator and skills-generator existed.
skill-name/
├── SKILL.md # Required: metadata + instructions
├── scripts/ # Optional: executable code
├── references/ # Optional: documentation
├── assets/ # Optional: templates, resources
└── ... # Any additional files or directories
Source: https://agentskills.io/specification
If you followed the various ADRs published at https://github.com/jabrena/cursor-rules-java/tree/main/documentation/adr, you may recall that when more than 10 rules were active in memory, Cursor (and similar tools at the time) did not run reliably, and you could hit the following issue:
If you are interested in this issue with older models, you can review it here: https://github.com/jabrena/cursor-rules-sandbox/blob/main/docs/message-too-long.md
So we changed the metadata included in the System prompts/Rules to address that issue and to use the rules in a manual workflow, as described here: https://github.com/jabrena/cursor-rules-java/blob/main/documentation/adr/ADR-002-configure-cursor-rules-manual-scope.md
Users could still use the System prompts/Rules in this way:
But now you can do the same with Skills. You can add the Skill you want to the context explicitly, or leave it to the AI tool to use or skip depending on the context—so you can achieve the same outcomes with Skills as you could with system prompts in the past.
On the main branch, a few resources about System-prompts/rules remain:
- All rules from v0.13.0: https://github.com/jabrena/cursor-rules-java/tree/main/.cursor/rules
- Getting Started: https://github.com/jabrena/cursor-rules-java/blob/main/documentation/GETTING-STARTED-SYSTEM-PROMPTS.md
That usage is deprecated in favor of Skills and will be removed in the coming months; the recommendation is to review the new documentation and adapt.
You can still download the last generated rules from release 0.13.0 if needed: https://github.com/jabrena/cursor-rules-java/releases/tag/0.13.0
Now that the serious part is out of the way, let's continue with the article.
Improvements in the Agile process
When you create a User Story, the flow not only generates the usual structure plus acceptance criteria in Gherkin format; it also reviews the user story as a whole using INVEST. INVEST is an acronym used in Agile to evaluate the quality of a user story, ensuring it is Independent, Negotiable, Valuable, Estimable, Small, and Testable.
Skills:
@014-agile-user-story
Improvements in the planning process
It is tedious to copy issue details from your issue tracker into the context of whichever AI tool you use. With that in mind, you can now access assigned issues more easily if you work with GitHub Issues or Jira. Those Skills combine well with @014-agile-user-story to turn the classic Anemic one line User Story into something richer.
Once the information is ready for development, you can convert it into a Change or Delta using OpenSpec.
How does OpenSpec work?
OpenSpec is a spec-driven change workflow: you capture what you want and how you will verify it before (or alongside) changing code and generators.
The scaffolding for any project using OpenSpec looks like this:
openspec/
└── changes/
└── add-profile-filters/
├── proposal.md
├── tasks.md
└── specs/profile/spec.md
└── specs/
config.yaml
Commands you will use often:
openspec init
openspec list
openspec status --change <change-id>
openspec show <change-name>
openspec new change <change-name>
openspec validate --all
openspec archive <change-name>
Further information about OpenSpec: https://openspec.dev/
When to use OpenSpec in daily work?
If you pick up a user story from any issue-tracking tool and it relates to a service you know well, you can use the following workflow directly:
User story > Create a Change in OpenSpec > Implement with Java Agents
But if you are less sure about the assigned user story, invest more time in the analysis phase:
User story > Create a Plan > Enhance the plan > Convert into multiple Changes in OpenSpec > Implement with Java Agents
Some factors to consider:
- Design incremental Deltas
- Review the tests
- Use TDD. (Consider TCR)
- Do not execute all changes at once. Finish one and review for potential technical debt.
Skills:
@042-planning-openspec@043-planning-github-issues@044-planning-jira
Improvements in the Implementation phase
Improvements in Maven
Now it is easier to update your pom.xml with @114-java-maven-search. On the other hand, the Maven-related skills are gradually gaining popularity.
Skills
@114-java-maven-search
Reinforced REST API development with new technologies
In the previous release, the project added Agents to implement plans. In this release, you can apply changes in a more granular way, or keep using Plans when the change is small. You can review your REST contracts with @701-technologies-openapi, reinforce your integration tests with @702-technologies-wiremock, and—most significantly for testing—use the new black-box testing capabilities with @703-technologies-fuzzing-testing based on CATS.
You can run black-box tests against your development environment using your OpenAPI specification.
Further information about CATS: https://github.com/Endava/cats
Skills
@701-technologies-openapi@702-technologies-wiremock@703-technologies-fuzzing-testing
Skill inventory
In version v0.14.0, the project ships 68 Skills.
You can install the Skills easily with:
npx skills add jabrena/cursor-rules-java --all --agent cursor
npx skills add jabrena/cursor-rules-java --all --agent claude-code
Once you have the skills installed, you can install the Agents with:
@003-agents-installation Install Agents in Cursor
@003-agents-installation Install Agents in Claude
What is the next step?
In the next release, the project will be renamed to reflect its evolution, and a few Skills will be refactored using notes from Tessl.
Do you still have questions about the project?
If you feel stuck using this project or have questions, you can attend the following workshop at Codemotion Madrid 2026:
