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/eser/rules/eser-rules-managernpx skills add eser/rules --skill eser-rules-managergit clone --depth 1 https://github.com/eser/rulesWhat 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 | $0.00037 | $0.00298 |
| Opus 5 | $0.00018 | $0.00149 |
| Sonnet 5 | $0.00007 | $0.00060 |
| Haiku 4.5 | $0.00004 | $0.00030 |
Grade A, and why
eser-rules-manager 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.
What it actually says
eser-rules: Development Practices Manager
Manages development rules across skills. Before working, apply all rules in
.claude/skills/*/SKILL.md.
Quick Start
- Identify scope → choose skill (or create new)
- Add/update rule in
.claude/skills/<name>/references/rules.md - Update
.claude/skills/<name>/SKILL.mdkey principles if needed - Validate:
npx -y claude-skills-cli validate .claude/skills/<name>
Skill Format
- SKILL.md: <50 lines, Quick Start + Key Principles + References
- references/: Detailed rules with Correct/Incorrect examples
- Frontmatter:
name(kebab-case),description(<1024 chars)
Skills by Scope
architecture-guidelines, design-principles, coding-practices,
javascript-practices, tooling-standards, go-practices,
security-practices, workflow-practices, ci-cd-practices
References
See skill-format.md for complete skill format requirements.
What ships with it
1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
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 · 34 lines · 37 tokens per session scan A c550ec841f35
eser-rules-manager is a skill published in the GitHub repository eser/rules (53 stars, last pushed 8mo ago), licensed Apache-2.0. It adds 37 tokens to every session and 298 once invoked, about $0.0002 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 2026-08-30.
Other skills, from other repositories
systematic-debugging
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brainstorming
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auto-perf-optimize
Run agent-driven VS Code performance or memory investigations. Use when asked to launch Code OSS, automate a VS Code scenario, run the Chat memory smoke runner, capture renderer heap snapshots, take workflow screenshots, compare run summaries, or drive a repeatable scenario before heap-snapshot analysis.
chat-perf
Run chat perf benchmarks and memory leak checks against the local dev build or any published VS Code version. Use when investigating chat rendering regressions, validating perf-sensitive changes to chat UI, or checking for memory leaks in the chat response pipeline.
chat-pet-sprite-creation
Use when creating or changing VS Code chat pet sprite art, sprite sheets, state animations, eye treatments, Stable/Insiders variants, or pet transitions under src/vs/workbench/contrib/chat/browser/widget/media/chatPet.
cpu-profile-analysis
Analyze V8/Chrome CPU profiles (.cpuprofile) and DevTools trace files (Trace-.json). Use when: profiling performance, investigating slow functions, comparing code paths, finding bottlenecks, analyzing timeToRequest, understanding call trees from sampling profiler data, analyzing layout/paint/rendering, investigating…