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 skills/eea/eea.agent.skills/composition-patternsnpx skills add eea/eea.agent.skills --skill composition-patternsgit clone --depth 1 https://github.com/eea/eea.agent.skillsWhat 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 | $0.00055 | $0.00891 |
| Opus 5 | $0.00028 | $0.00445 |
| Sonnet 5 | $0.00011 | $0.00178 |
| Haiku 4.5 | $0.00006 | $0.00089 |
Grade A, and why
composition-patterns 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 — 125 lines — stays where its author put it; the contents beside it link to each section on GitHub.
React Composition Patterns
Composition patterns for building flexible, maintainable React components. Avoid boolean prop proliferation by using compound components, lifting state, and composing internals. These patterns make codebases easier for both humans and AI agents to work with as they scale.
When to Apply
Reference these guidelines when:
- Refactoring components with many boolean props
- Building reusable component libraries
- Designing flexible component APIs
- Reviewing component architecture
- Working with compound components or context providers
Rule Categories by Priority
| Priority | Category | Impact | Prefix |
|---|---|---|---|
| 1 | Component Architecture | HIGH | architecture- |
| 2 | State Management | MEDIUM | state- |
| 3 | Implementation Patterns | MEDIUM | patterns- |
| 4 | React 19 APIs | MEDIUM | react19- |
Quick Reference
1. Component Architecture (HIGH)
architecture-avoid-boolean-props- Don't add boolean props to customize behavior; use compositionarchitecture-compound-components- Structure complex components with shared context
2. State Management (MEDIUM)
state-decouple-implementation- Provider is the only place that knows how state is managedstate-context-interface- Define generic interface with state, actions, meta for dependency injectionstate-lift-state- Move state into provider components for sibling access
3. Implementation Patterns (MEDIUM)
patterns-explicit-variants- Create explicit variant components instead of boolean modespatterns-children-over-render-props- Use children for composition instead of renderX props
4. React 19 APIs (MEDIUM)
⚠️ React 19+ only. Skip this section if using React 18 or earlier.
react19-no-forwardref- Don't useforwardRef; useuse()instead ofuseContext()
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 · 125 lines · 55 tokens per session scan A 0b18ded690cc
composition-patterns is a skill published in the GitHub repository eea/eea.agent.skills (2 stars, last pushed 25d ago), licensed MIT. It adds 55 tokens to every session and 891 once invoked, about $0.0003 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.
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