Borrowing it
Nothing to install: this file belongs to SeJonJ/ChatForYou. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/SeJonJ/ChatForYou/chatforyou_v2_sage/.claude/agents/chatforyou-backend-expert.mdgit clone --depth 1 https://github.com/SeJonJ/ChatForYouWrote 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/sejonj/chatforyou/chatforyou-backend-expert)<a href="https://agentmods.dev/agents/sejonj/chatforyou/chatforyou-backend-expert"><img src="https://agentmods.dev/badge/agents/sejonj/chatforyou/chatforyou-backend-expert/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/agents/sejonj/chatforyou/chatforyou-backend-expert"><img src="https://agentmods.dev/badge/agents/sejonj/chatforyou/chatforyou-backend-expert.svg" alt="Reviewed on agentmods" width="80" 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 5.1 | $0.00216 | $0.01673 |
| Opus 5.5 | $0.00086 | $0.00669 |
| Sonnet 5.5 | $0.00043 | $0.00335 |
| Haiku 4.5 | $0.00022 | $0.00167 |
Grade A, and why
chatforyou-backend-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 1mo 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.
The source is not reproduced here
No licence file
A repository with no LICENSE is all rights reserved by default, so the body is not copied here. The metadata, the measurements and the link are.
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.
- 1mo ago First seen · 126 lines · 216 tokens per session scan A 48aeeb56d384
chatforyou-backend-expert is an agent published in the GitHub repository SeJonJ/ChatForYou (109 stars, last pushed 4d ago), with no licence file. It adds 216 tokens to every session and 1,673 once invoked, about $0.0009 per session on Opus 5.5. 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 2026-09-04.
Other agents, from other repositories
java-software-architect-review
Provides expert Java software architecture review capability, specializing in Clean Architecture, Domain-Driven Design (DDD), and Spring Boot patterns. Reviews Java codebases for architectural integrity, proper bounded contexts, and SOLID principles. Use proactively when making Java architectural decisions, DDD…
spring-boot-backend-development-expert
Provides expert Spring Boot backend development capability, specializing in feature implementation, architecture, and best practices. Use proactively when working on Spring Boot development tasks, REST API implementation, and backend architecture decisions.
spring-architect
Phase 3 — design the Spring Boot 4 feature, decompose into TDD-shaped tasks, write ADRs. Use proactively when the user asks for design, plan, or runs /plan.
backend-engineer
Use this agent when building Spring Boot 4 applications with Java 25, REST APIs, Spring Data JPA, Flyway migrations, Spring Security 7, OpenAPI documentation, and production-ready backend patterns.
spring-boot-unit-testing-expert
Provides expert unit testing capability with Spring Test, JUnit 5, and Mockito for Spring Boot applications. Handles comprehensive test strategies, test architecture, and testing best practices. Use proactively when writing unit tests, improving test coverage, or reviewing testing strategies.
prompt-engineering-expert
Provides expert prompt engineering capabilities specializing in advanced prompting techniques, LLM optimization, and AI system design. Masters chain-of-thought, constitutional AI, and production prompt strategies. Use PROACTIVELY for prompt creation, optimization, document/code analysis prompts, or AI system design.…