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/st0012/ruby-skills/ruby-resource-mapnpx skills add st0012/ruby-skills --skill ruby-resource-mapgit clone --depth 1 https://github.com/st0012/ruby-skillsWhat 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 | $0.00022 | $0.00791 |
| Opus 5 | $0.00011 | $0.00396 |
| Sonnet 5 | $0.00004 | $0.00158 |
| Haiku 4.5 | $0.00002 | $0.00079 |
Grade A, and why
ruby-resource-map 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 — 74 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Ruby Knowledge
Authoritative resource map for Ruby development. Use these sources rather than searching broadly.
Never use these sources:
- ruby-doc.org
- apidock.com
Official Documentation
Primary source: https://docs.ruby-lang.org/en/
Other Useful Resources
- https://rubyreferences.github.io/rubychanges/ - Version-by-version changelog with examples
- https://railsatscale.com/ - Shopify engineering blog (Latest updates on Ruby and its toolings)
Core & Standard Library
| Term | Meaning |
|---|---|
| Default gem | Ships with Ruby, cannot uninstall |
| Bundled gem | Ships with Ruby, can uninstall/replace |
| Standard library | Part of Ruby itself, not a gem |
To check which gem versions ship with each Ruby release: https://stdgems.org/
Testing Frameworks
| Framework | GitHub | Documentation |
|---|---|---|
| minitest | https://github.com/minitest/minitest | https://docs.seattlerb.org/minitest/ |
| test-unit | https://github.com/test-unit/test-unit | https://test-unit.github.io/ |
Typing Ecosystem
Two type definition formats exist in Ruby:
- RBI - Sorbet's format. Uses Ruby DSL syntax (
sig { ... }) in.rband.rbifiles. - RBS - Official Ruby format (Ruby 3.0+). Dedicated syntax in
.rbsfiles or inline as comments.
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 · 74 lines · 22 tokens per session scan A d190c86b8e7e
ruby-resource-map is a skill published in the GitHub repository st0012/ruby-skills (125 stars, last pushed 2mo ago), licensed MIT. It adds 22 tokens to every session and 791 once invoked, about $0.0001 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.
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