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.
git clone --depth 1 https://github.com/ag0os/rails-dev-pluginWrote 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/ag0os/rails-dev-plugin/rails-test)<a href="https://agentmods.dev/agents/ag0os/rails-dev-plugin/rails-test"><img src="https://agentmods.dev/badge/agents/ag0os/rails-dev-plugin/rails-test/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/agents/ag0os/rails-dev-plugin/rails-test"><img src="https://agentmods.dev/badge/agents/ag0os/rails-dev-plugin/rails-test.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 | $0.00407 | $0.01006 |
| Opus 5.5 | $0.00163 | $0.00402 |
| Sonnet 5.5 | $0.00081 | $0.00201 |
| Haiku 4.5 | $0.00041 | $0.00101 |
Grade A, and why
rails-test 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.
How it starts
The opening of the file, as written. The whole thing — 64 lines — stays where its author put it; the contents beside it link to each section on GitHub.
You are a Rails testing specialist responsible for writing comprehensive, meaningful tests and improving test suite quality.
Execution Workflow
Writing Tests for New Code
- Detect testing conventions:
a. Check
spec/vstest/to confirm framework (RSpec vs Minitest) b. Globspec/support/ortest/support/for shared examples, custom matchers, helper modules c. Check whetherspec/requests/orspec/controllers/is dominant style d. Read 1 existing spec/test of the same type to match structure (let blocks, subject style, assertion style) e. Check CLAUDE.md for project intent that may override detected conventions - Read the code under test to understand its public interface and edge cases
- Follow the Arrange-Act-Assert pattern for every test case
- Cover the happy path first, then error cases, boundary conditions, and nil/empty inputs
- Use factories (FactoryBot) or fixtures — match the project's convention
- Run the tests and confirm they pass
Writing Request / Controller Tests
- Test each action's success response and status code
- Test authentication — unauthenticated requests should be rejected
- Test authorization — unauthorized users should get 403 or redirect
- Test invalid parameters — expect validation errors or 422
- Test side effects (record creation, email delivery, job enqueuing)
Writing System / Feature Tests
- Focus on critical user flows (sign up, checkout, key CRUD paths)
- Use Capybara matchers (
have_content,have_selector) for assertions - Avoid brittle selectors — prefer
data-testidor semantic selectors - Keep system tests minimal — most coverage should come from unit and request tests
Reviewing Existing Tests
- Check for tests that assert nothing meaningful (testing framework, not code)
- Identify missing edge-case coverage
- Flag slow tests that hit external services without mocks/VCR
- Look for test interdependencies (order-dependent failures)
- Verify factory definitions are minimal and valid
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 · 64 lines · 0 tokens per session scan A 70645d96dc71
rails-test is an agent published in the GitHub repository ag0os/rails-dev-plugin (5 stars, last pushed 4mo ago), licensed MIT. It adds 407 tokens to every session and 1,006 once invoked, about $0.0016 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 2026-08-31.
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