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/slbug/claude-ruby-grape-rails/plugin-reviewgit clone --depth 1 https://github.com/slbug/claude-ruby-grape-railsWhat 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 | $0.05496 | $0.05496 |
| Opus 5 | $0.02748 | $0.02748 |
| Sonnet 5 | $0.01099 | $0.01099 |
| Haiku 4.5 | $0.00550 | $0.00550 |
Grade A, and why
claude-ruby-grape-rails plugin-review.instructions.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 2d 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 — 406 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Plugin File Review Rules
Audience: Agents, Not Humans
Plugin docs (agents/, skills/, references/) load into agent
context at runtime. Flag prose that violates the imperative-only
rule:
- Tutorial narration ("first do X, then Y") → flag, suggest imperative rewrite
- Reasoning preludes before commands → flag
#thinking/checklist lines inside Bash command bodies (preference #6) → flag, suggest markdown table or prose lead-in- Long explanatory paragraphs where a table fits → flag
Exception files (human-facing, narrative OK): README.md,
CHANGELOG.md, scripts/, lab/eval/.
Agent Conventions (plugins/**/agents/*.md)
- Agents use YAML frontmatter. Common: name, description, model,
disallowedTools, omitClaudeMd, skills, memory. Also valid per CC docs:
tools, effort, maxTurns, background, isolation. The general subagent
reference (https://docs.claude.com/en/docs/claude-code/sub-agents)
also lists
colorandinitialPrompt, but the plugin-supported set documented at https://docs.claude.com/en/docs/claude-code/plugins-reference does NOT include them — CC silently drops these on plugin-shipped agents. Do NOT add them to plugin agents underplugins/**/agents/ - Prefer denylist-only (
disallowedTools:) over allowlist (tools:). A missingtools:field is intentional — agents inherit all tools minus those in disallowedTools - Artifact-writing agents:
disallowedTools: Edit, NotebookEdit, Agent, EnterWorktree, ExitWorktree, Skill - Conversation-only agents add
Writeto the above - NO agent declares or invokes
Agent— orchestration lives in skill bodies (main session). See.claude/rules/agent-development.md§ "Subagents Are Leaf Workers" for full doctrine. - Agents with intentionally narrow tool sets (web-researcher,
output-verifier, ruby-gem-researcher) use
tools:allowlists — this is correct omitClaudeMd: trueis correct for specialist agents that do not need contributor CLAUDE.md context- Do NOT flag
permissionModeas missing — Claude Code ignores it on plugin agents - Model tiers: opus for security-critical agents, sonnet for most specialists,
haiku for mechanical tasks.
opusplanis a session-level/modelalias only (the subagent frontmatter table at https://docs.claude.com/en/docs/claude-code/sub-agents does NOT list it as a valid subagentmodelvalue) — do NOT flag its absence from agent frontmatter as a gap - Descriptions must be <= 250 characters
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.
- 2d ago First seen · 406 lines · 5,496 tokens per session scan A 70e1a05c4104
claude-ruby-grape-rails plugin-review.instructions.md is an instructions file published in the GitHub repository slbug/claude-ruby-grape-rails (7 stars, last pushed 3d ago), licensed MIT. It adds 5,496 tokens to every session, about $0.0275 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
Skill_Seekers AGENTS.md
Instructions for yusufkaraaslan/Skill_Seekers, covering agents.md - skill seekers, project overview, key capabilities, setup and with dev tools (pytest, ruff, mypy, coverage).
obsidian-mcp-server AGENTS.md
Instructions for cyanheads/obsidian-mcp-server, covering agent protocol, what's next?, core rules, patterns and tool — obsidianlisttags.
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Instructions for zendev-sh/goai, covering agents.md - goai, commands, architecture, key rules and adding providers.
speckit-companion CLAUDE.md
Instructions for alfredoperez/speckit-companion, covering claude.md, where things are documented, gotchas, two extensions, two sets of docs and /releases/latest resolves across both tag namespaces.
agent-toolkit AGENTS.md
Instructions for ulises-jeremias/agent-toolkit, covering agents.md — ai agent contract, what this toolkit does, repository structure, operating rules and how to add a skill.
best-of-Agent-Harnesses CLAUDE.md
Claude Code instructions for RyanAlberts/best-of-Agent-Harnesses, covering repo notes for ai coding agents, commit identity (required), branching and pushing (required), verifying contribution credit (required) and how the list is generated.