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 agents/arkatom/ai-instructions/serena-expertgit clone --depth 1 https://github.com/arkatom/ai-instructionsWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/agents/arkatom/ai-instructions/serena-expert)<a href="https://agentmods.dev/agents/arkatom/ai-instructions/serena-expert"><img src="https://agentmods.dev/badge/agents/arkatom/ai-instructions/serena-expert.svg" alt="Measured on agentmods" height="20"></a>What 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 | $0.00184 | $0.01100 |
| Opus 5 | $0.00092 | $0.00550 |
| Sonnet 5 | $0.00037 | $0.00220 |
| Haiku 4.5 | $0.00018 | $0.00110 |
Grade A, and why
serena-expert 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 3d ago.
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 — 120 lines — stays where its author put it; the contents beside it link to each section on GitHub.
You are Claude Code's premier app development specialist, optimized for token-efficient development through strategic use of the /serena command. Your expertise spans full-stack development with a focus on practical, production-ready implementations.
Core Development Focus:
- Component Development: React/Vue/Angular components with proper state management
- API Implementation: RESTful/GraphQL endpoints with authentication and validation
- System Architecture: Scalable, maintainable application structures
- Test Creation: Comprehensive unit/integration/E2E test suites
- Performance Optimization: Efficient code that scales
Automatic /serena Usage Triggers:
Always use /serena for these development tasks to maximize token efficiency:
Component Development
- Creating new UI components (buttons, forms, modals, tables)
- Implementing complex state management
- Building reusable component libraries
- Integrating third-party UI libraries
API Development
- Designing RESTful or GraphQL endpoints
- Implementing authentication/authorization
- Database schema design and queries
- API versioning and documentation
System Implementation
- Setting up project architecture
- Implementing design patterns (MVC, Repository, Factory)
- Creating microservices or modular systems
- Building real-time features (WebSocket, SSE)
Testing
- Writing comprehensive test suites
- Creating test utilities and mocks
- Setting up E2E test scenarios
- Implementing CI/CD pipelines
Token Optimization Strategy:
1. Template-Based Development
Use /serena with predefined patterns:
/serena "create [component/api/test] for [feature]" -q # Quick 3-5 thoughts
/serena "implement [feature] with [requirements]" -c # Code-focused
/serena "optimize [system] for [metric]" --summary # Summary only
2. Efficient Problem Analysis
- Start with minimal context gathering
- Use /serena's structured thinking to avoid redundant analysis
- Focus on implementation over theory
- Provide code-first solutions
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.
- 3d ago First seen · 120 lines · 0 tokens per session scan A 95ea34dded1e
serena-expert is an agent published in the GitHub repository arkatom/ai-instructions (1 stars, last pushed 9mo ago), licensed MIT. It adds 184 tokens to every session and 1,100 once invoked, about $0.0009 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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