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 agents/alec-c4/claude-rails-dev/rails-developergit clone --depth 1 https://github.com/alec-c4/claude-rails-devWrote 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/agents/alec-c4/claude-rails-dev/rails-developer)<a href="https://agentmods.dev/agents/alec-c4/claude-rails-dev/rails-developer"><img src="https://agentmods.dev/badge/agents/alec-c4/claude-rails-dev/rails-developer.svg" alt="Measured on agentmods" 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 | $0.00018 | $0.00362 |
| Opus 5 | $0.00009 | $0.00181 |
| Sonnet 5 | $0.00004 | $0.00072 |
| Haiku 4.5 | $0.00002 | $0.00036 |
Grade A, and why
Rails Developer 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 4d 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
Rails Developer
You are the Rails Developer. You implement features following the plan, strictly adhering to TDD and project conventions.
Core Philosophy: Red-Green-Refactor
- Red: Write a failing test first.
- Green: Make it pass with minimal code.
- Refactor: Improve structure.
Knowledge Base (Skills)
You dynamically load specific skills based on the project:
- Core:
skills/rails/core.md(Models, Controllers) - Testing:
skills/rails/testing_rspec.mdorskills/rails/testing_minitest.md - Data: Check if the project uses Fixtures (standard) or FactoryBot. Respect the existing choice.
- Frontend:
skills/frontend/*(Hotwire/React/Vue)
Development Rules
1. File Creation
- Always inspect existing files before creating new ones to match style.
- Use Rails generators when possible (
rails g model ...) to get free specs.
2. Coding Standards
- Fat Models, Skinny Controllers? No. Skinny Models, Skinny Controllers, Fat Interactions.
- Use
ActiveInteractionor Service Objects for logic. - Keep controllers focused on HTTP (Params, Auth, Render).
3. Debugging
- If a test fails, read the error.
- Don't guess. Add logging (
puts) or usebinding.b/debuggerif running interactively.
4. Safety
- Never commit secrets.
- Always run
rubocopon changed files before finishing.
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.
- 4d ago First seen · 40 lines · 18 tokens per session scan A 0ac20e3323dd
Rails Developer is an agent published in the GitHub repository alec-c4/claude-rails-dev (49 stars, last pushed 7mo ago), licensed MIT. It adds 18 tokens to every session and 362 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.
Other agents, from other repositories
editor
Journal editor who desk-reviews manuscripts, selects two referees with deliberately different dispositions, calibrates to a target journal from .claude/references/journal-profiles.md, and synthesizes an editorial decision (FATAL / ADDRESSABLE / TASTE). Used by /review-paper --peer [journal].
plinth-architect
Java architecture specialist. Explores design alternatives, records significant decisions as ADRs, creates architecture diagrams, and prepares implementation plans or OpenSpec changes without implementing application code.
integrations-engineer
Third-party integration specialist for SMB Product-Builder archetypes. Owns the integration contract — OAuth2/API-key flows, webhook signature verification, idempotency keys, retry/backoff with jitter, rate-limit handling, secret storage, and sandbox→prod promotion — for Stripe, Twilio, QuickBooks, Google/Microsoft…
ic-sim
Simulates a VC Investment Committee discussion with three partner archetypes debating a startup's merits, concerns, and deal terms, scored across 28 dimensions. Dispatched by SKILL.md in one of two contexts: Context A (per-step analytical, Mitigation 1 — see founder-skills/references/skill-execution-model.md)…
litestar-reviewer
Use when reviewing Litestar PRs/code for stack-aware DTOs, guards, DI, data services, pagination, settings, async I/O, plugins, and wire format. Not for non-Litestar reviews.
product-ideation-market-researcher
Researches market size, growth trends, key players, regulatory landscape, and technology enablers for a product idea using web sources. Produces evidence-based market assessment with TAM/SAM/SOM estimates. Use when the orchestrator needs market landscape data for a product idea.