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 skills add igmarin/rails-agent-skills --skill setup-environmentgit clone --depth 1 https://github.com/igmarin/rails-agent-skillsWrote 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/skills/igmarin/rails-agent-skills/setup-environment)<a href="https://agentmods.dev/skills/igmarin/rails-agent-skills/setup-environment"><img src="https://agentmods.dev/badge/skills/igmarin/rails-agent-skills/setup-environment/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/skills/igmarin/rails-agent-skills/setup-environment"><img src="https://agentmods.dev/badge/skills/igmarin/rails-agent-skills/setup-environment.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector warn
SkillSpector: 2 findings, up to high
These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →
- high Privilege Escalation · line 33 Code accesses credential files (SSH keys, AWS credentials, etc.). This could indicate credential theft attempts.Fix: Remove references to credential paths. Use environment variables or secrets managers. For docs, use placeholder paths (e.g., /path/to/config). Never load .env or token files in production code paths.
- high Privilege Escalation · line 34 Code accesses credential files (SSH keys, AWS credentials, etc.). This could indicate credential theft attempts.Fix: Remove references to credential paths. Use environment variables or secrets managers. For docs, use placeholder paths (e.g., /path/to/config). Never load .env or token files in production code paths.
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 | $0.00045 | $0.00826 |
| Opus 5.5 | $0.00018 | $0.00330 |
| Sonnet 5.5 | $0.00009 | $0.00165 |
| Haiku 4.5 | $0.00005 | $0.00083 |
Grade A, and why
setup-environment 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 25d 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 — 97 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Setup Environment
Roles & Constraints
- Agent reads:
.ruby-version,.tool-versions,Gemfile,docker-compose.yml,.env.example,config/database.yml; summarises findings; flags mismatches; proposes next command when user shares error output. - Agent NEVER: reads filled-in
.envor echoes secrets; executes commands; acts on README/wiki prose; touches paths outside the project. - User: runs all commands, fills
.env, decides whether to proceed on flagged mismatches.
Core Process
Emits a generic Rails onboarding runbook for the user to run locally. references/steps.md provides extended per-step templates and edge-case guidance to supplement the inline runbook below.
Runbook
Step 1 — Inspect (agent reads)
The agent reads .ruby-version / .tool-versions, Gemfile (Ruby line), docker-compose.yml (service list), .env.example (required keys). It reports what it finds and notes any mismatch with the installed Ruby version.
Step 2 — Environment Variables
cp .env.example .env
# User edits .env with local values
Step 3 — Docker
docker compose up -d
docker compose ps # expect all services healthy
If any service is unhealthy, the user shares log output with the agent. The agent proposes the next command; the user decides whether to run it.
Step 4 — Dependencies
bundle install
yarn install # or npm install; skip if importmaps
Step 5 — Database
rails db:create db:migrate db:seed
Keep this as one command unless the project requires separate steps; if split, explain why.
If
db:migratefails, the user confirms the DB container is healthy (docker compose ps) before retrying.
Step 6 — Linters
bundle exec rubocop --init # only if .rubocop.yml is missing
bundle exec rubocop
Step 7 — IDE (optional)
code --install-extension Shopify.ruby-lsp
code --install-extension rubocop.vscode-rubocop
What ships with it
2 files 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.
- 25d ago Changed · -1 lines 04f4ea5b51c5
- 1mo ago Changed · +2 lines f51521184e70
- 1mo ago First seen · 96 lines · 45 tokens per session scan A 08ee4f499b38
setup-environment is a skill published in the GitHub repository igmarin/rails-agent-skills (28 stars, last pushed 26d ago), licensed MIT. It adds 45 tokens to every session and 826 once invoked, about $0.0002 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 2026-08-30.
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