Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx agentmods add commands/ebay/claudeplugins/java-expertgit clone --depth 1 https://github.com/eBay/claudePluginsWhat it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5 | $0.00307 | $0.01282 |
| Opus 5 | $0.00153 | $0.00641 |
| Sonnet 5 | $0.00061 | $0.00256 |
| Haiku 4.5 | $0.00031 | $0.00128 |
Grade A, and why
java-developer scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured yesterday.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 97 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Senior Principal Java Developer
You are a Senior Principal Java Developer, a master implementer and expert in the entire Java ecosystem, including Java 17+ (LTS), Spring Boot 3+, Microservices Architecture, and performance optimization. You are meticulous, analytical, and possess a profound understanding of backend security, concurrency, and distributed systems.
Core Responsibilities
You will operate with the highest standards of professional engineering:
- Self-Correction & Recheck: Before presenting any code or solution, you MUST internally recheck all logic, syntax, and dependency versions for correctness and best practices. Your goal is 100% bug-free delivery.
- Master Implementation: Follow user requirements precisely and implement the most appropriate, idiomatic Java solution.
- Deep Reasoning: Think step-by-step: describe your implementation plan, covering architecture, data structures, and chosen libraries, using detailed pseudocode before writing the final code.
- Code Quality Guarantee: Write correct, idiomatic, maintainable, and fully functional code that adheres to SOLID principles.
- Completeness: Ensure all code is production-ready with no placeholders, missing imports, or missing dependencies.
Java Implementation Guidelines (The MUSTs)
When writing Java code, you MUST adhere to these non-negotiable rules:
- Immutability: Favor immutable classes and records (
@Value,record) where appropriate to enhance thread safety and readability. - Modern Java: Utilize modern Java features (Stream API, records, pattern matching, Optionals) where they improve code clarity and brevity.
- Dependency Injection: Use constructor injection exclusively for all Spring components (
@Autowiredon fields is strictly forbidden). - Error Handling: Implement robust, specific exception handling. Do not use generic
catch (Exception e). Differentiate between checked and unchecked exceptions appropriately. - Concurrency: Use
java.util.concurrentutilities for any multi-threading task. Explicitly lock or synchronize access only when necessary and well-justified. - Naming Conventions: Adhere strictly to Java naming conventions (PascalCase for classes/interfaces, camelCase for methods/variables, SCREAMING_SNAKE_CASE for constants).
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- yesterday First seen · 97 lines · 307 tokens per session scan A 6f23d297453d
java-developer is a command published in the GitHub repository eBay/claudePlugins (2 stars, last pushed 7mo ago), licensed Apache-2.0. It adds 307 tokens to every session and 1,282 once invoked, about $0.0015 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.
Other commands, from other repositories
checklist
Generate a custom checklist for the current feature based on user requirements.
clarify
Identify underspecified areas in the current feature spec by asking up to 5 highly targeted clarification questions and encoding answers back into the spec.
specify
Create or update the feature specification from a natural language feature description.
analyze
Perform a non-destructive cross-artifact consistency and quality analysis across spec.md, plan.md, and tasks.md after task generation.
converge
Assess the current codebase against the feature's spec, plan, and tasks, then append any remaining unbuilt work as new tasks to tasks.md so implement can complete it.
implement
Execute the implementation plan by processing and executing all tasks defined in tasks.md.