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 instructions/jontsai/claude-plugins/agents-mdgit clone --depth 1 https://github.com/jontsai/claude-pluginsWhat 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 | $0.00539 | $0.00539 |
| Opus 5 | $0.00269 | $0.00269 |
| Sonnet 5 | $0.00108 | $0.00108 |
| Haiku 4.5 | $0.00054 | $0.00054 |
Grade A, and why
claude-plugins AGENTS.md 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 — 82 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Agent Guidelines
Guidelines for LLMs working on this codebase.
Project Overview
This is a Claude Code plugins marketplace. It contains:
- Marketplace definition:
.claude-plugin/marketplace.json - Plugins:
plugins/<name>/directories - Validation scripts:
scripts/validate_*.py - CI workflow:
.github/workflows/validate.yml
Key Constraints
Plugin Structure
-
Each plugin needs
.claude-plugin/plugin.jsonwith:name,description,version,author
-
Skills are auto-discovered from
skills/*/SKILL.md- Do NOT add explicit
skillsarray to marketplace.json - Each SKILL.md needs frontmatter with
nameanddescription
- Do NOT add explicit
-
hooks.json format is specific:
- Must be object keyed by event name, NOT an array
- Use
${CLAUDE_PLUGIN_ROOT}for paths in commands
Validation
Always run before committing:
./scripts/validate.sh
Or run individual validators:
python3 scripts/validate_json.py
python3 scripts/validate_marketplace.py
python3 scripts/validate_skills.py
python3 scripts/validate_hooks.py
Common Mistakes to Avoid
- hooks.json as array: Must be
{"hooks": {"EventName": [...]}}not{"hooks": [...]} - Explicit skills array: Don't add - causes path doubling
- Missing plugin.json: Each plugin needs
.claude-plugin/plugin.json - echo for colors: Use
printfwith\e[0;32mescapes in Makefiles
Testing Plugin Installation
# Add marketplace
/plugin marketplace add jontsai/claude-plugins
# Install plugin
/plugin install researcher@jontsai
# Check installation
/plugin list
File Locations
| Purpose | Path |
|---|---|
| Marketplace def | .claude-plugin/marketplace.json |
| Plugin metadata | plugins/<name>/.claude-plugin/plugin.json |
| Plugin hooks | plugins/<name>/hooks/hooks.json |
| Skills | plugins/<name>/skills/<skill>/SKILL.md |
| Validation | scripts/validate_*.py |
| CI | .github/workflows/validate.yml |
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 · 82 lines · 539 tokens per session scan A e64c8b992fe4
claude-plugins AGENTS.md is an instructions file published in the GitHub repository jontsai/claude-plugins (6 stars, last pushed 22d ago), licensed MIT. It adds 539 tokens to every session, about $0.0027 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.
Other instructions, from other repositories
pm-skills CLAUDE.md
Instructions for phuryn/pm-skills, covering claude.md, project overview, repo structure, the 9 plugins and key design rules.
claude-code-rules CLAUDE.md
Instructions for NikiforovAll/claude-code-rules, covering claude.md, repository overview, repo structure, website and important.
claude-plugins CLAUDE.md
Instructions for sgaunet/claude-plugins, covering claude.md, repository overview, architecture, marketplace structure and agent architecture.
Product-Marketing-Skills AGENTS.md
Instructions for stefanoskarakasis/Product-Marketing-Skills, covering agents.md, repository overview, repository structure, build / lint / test commands and agent skills specification.
Product-Marketing-Skills CLAUDE.md
Instructions for stefanoskarakasis/Product-Marketing-Skills, covering claude.md, versioning & releases, release procedure (manual, until ci enforcement exists) and after any repo change.
PM-Copilot-by-Product-Faculty CLAUDE.md
Claude Code instructions for Productfculty-aipm/PM-Copilot-by-Product-Faculty, covering pm copilot — global instructions, session start protocol, memory update protocol, context loading (all pm operations) and framework defaults.