Getting it into your agent
This one installs as part of its plugin. Adding the marketplace and installing the plugin brings it with everything else the plugin ships.
/plugin marketplace add slbug/claude-ruby-grape-rails/plugin install ruby-grape-railsWrote 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/slbug/claude-ruby-grape-rails/rb-trace)<a href="https://agentmods.dev/skills/slbug/claude-ruby-grape-rails/rb-trace"><img src="https://agentmods.dev/badge/skills/slbug/claude-ruby-grape-rails/rb-trace/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/slbug/claude-ruby-grape-rails/rb-trace"><img src="https://agentmods.dev/badge/skills/slbug/claude-ruby-grape-rails/rb-trace.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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 | $0.00043 | $0.00385 |
| Opus 5.5 | $0.00017 | $0.00154 |
| Sonnet 5.5 | $0.00009 | $0.00077 |
| Haiku 4.5 | $0.00004 | $0.00038 |
Grade A, and why
rb:trace 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 1mo 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
Trace Execution
Follow the path from the entry point through:
- routes and mounted Grape APIs
- controllers/endpoints
- service or command objects
- models and queries
- jobs, broadcasts, and cache writes
Write the trace as a short step-by-step chain with file paths.
Agent Dispatch
This is a skill (/rb:trace), not an agent. Do NOT spawn rb-trace or
rb:trace via the Agent tool. For agent-based deep tracing, use call-tracer
(subagent_type: "ruby-grape-rails:call-tracer").
References
| Need | Reference |
|---|---|
| where tracing begins (controllers, Grape endpoints, jobs, rake, webhooks, middleware) | ${CLAUDE_SKILL_DIR}/references/entry-points.md |
| extracting argument patterns from call sites | ${CLAUDE_SKILL_DIR}/references/argument-extraction.md |
| Prism, TracePoint, RuboCop AST, Steep, Pronto | ${CLAUDE_SKILL_DIR}/references/static-analysis-tools.md |
| production-incident triage flow (when trace is for a live failure) | ${CLAUDE_PLUGIN_ROOT}/skills/investigate/references/incident-playbook.md |
Related — invoke manually if needed
- Live runtime introspection (Tidewave) →
/rb:runtime(Tidewave runtime introspection)
What ships with it
3 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.
- 1mo ago First seen · 39 lines · 43 tokens per session scan A 06f54b17e022
rb:trace is a skill published in the GitHub repository slbug/claude-ruby-grape-rails (7 stars, last pushed 16d ago), licensed MIT. It adds 43 tokens to every session and 385 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 2026-09-03.
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