SOLID principles for Java 21+. Files < 100 lines, interfaces separated, modular architecture. Modules MANDATORY.
From fuse-solidnpx claudepluginhub fusengine/agents --plugin fuse-solidThis skill uses the workspace's default tool permissions.
references/architecture-patterns.mdreferences/dependency-inversion.mdreferences/interface-segregation.mdreferences/liskov-substitution.mdreferences/open-closed.mdreferences/single-responsibility.mdreferences/solid-principles.mdreferences/templates/error.mdreferences/templates/interface.mdreferences/templates/module.mdreferences/templates/repository.mdreferences/templates/service.mdreferences/templates/test.mdDesigns and optimizes AI agent action spaces, tool definitions, observation formats, error recovery, and context for higher task completion rates.
Enables AI agents to execute x402 payments with per-task budgets, spending controls, and non-custodial wallets via MCP tools. Use when agents pay for APIs, services, or other agents.
Compares coding agents like Claude Code and Aider on custom YAML-defined codebase tasks using git worktrees, measuring pass rate, cost, time, and consistency.
Before ANY implementation, use TeamCreate to spawn 3 agents:
Before writing ANY new code:
modules/core/services/, modules/core/interfaces/modules/core/| Layer | Location | Max Lines |
|---|---|---|
| Controllers | modules/[feature]/controllers/ | 50 |
| Services | modules/[feature]/services/ | 100 |
| Repositories | modules/[feature]/repositories/ | 100 |
| Interfaces | modules/[feature]/interfaces/ | 30 |
| Models/DTOs | modules/[feature]/models/ | 50 |
| Shared | modules/core/{services,interfaces,models}/ | - |
NEVER use flat src/ structure - always modules/[feature]/
| Rule | Value |
|---|---|
| File limit | 100 lines (split at 90) |
| Controllers | < 50 lines, delegate to services |
| Interfaces | modules/[feature]/interfaces/ ONLY |
| Javadoc | Every public method documented |
| Records | Use for DTOs (Java 16+) |
| Sealed | Use for restricted hierarchies (Java 17+) |
| Topic | Reference | When to consult |
|---|---|---|
| SOLID Overview | solid-principles.md | Quick reference |
| SRP | single-responsibility.md | Fat classes |
| OCP | open-closed.md | Adding providers |
| LSP | liskov-substitution.md | Contracts |
| ISP | interface-segregation.md | Fat interfaces |
| DIP | dependency-inversion.md | Injection |
| Architecture | architecture-patterns.md | Modular patterns |
| Template | When to use |
|---|---|
| module.md | Feature module structure |
| service.md | Business logic service |
| interface.md | Contract definition |
| repository.md | Data access layer |
| error.md | Custom exceptions |
| test.md | Unit tests with mocks |
| Anti-Pattern | Fix |
|---|---|
| Files > 100 lines | Split at 90 |
| Interfaces in impl files | Move to interfaces/ directory |
new ConcreteClass() in services | Use dependency injection |
Flat src/ structure | Use modules/[feature]/ |
| God classes | Split by responsibility |