What is rails_ai_agents AGENTS.md?

A project guide describing the Rails application's setup, technologies, architecture, commands, and testing approach.

It helps agents work with the Rails codebase, including its models, services, views, authorization, jobs, database, and deployment setup.

It gives a coding agent the project context needed to make changes that fit the existing structure.

How ThibautBaissac/rails_ai_agents configures Codex and OpenCode

Reuse

Borrowing it

Nothing to install: this file belongs to ThibautBaissac/rails_ai_agents. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file

curl -O https://raw.githubusercontent.com/ThibautBaissac/rails_ai_agents/main/AGENTS.md

Clone the repo

git clone --depth 1 https://github.com/ThibautBaissac/rails_ai_agents

Made for: Codex, OpenCode.

Wrote 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.

README.md

[![agentmods](https://agentmods.dev/badge/instructions/thibautbaissac/rails_ai_agents/agents-md/github.svg)](https://agentmods.dev/instructions/thibautbaissac/rails_ai_agents/agents-md)

Your own site

<a href="https://agentmods.dev/instructions/thibautbaissac/rails_ai_agents/agents-md"><img src="https://agentmods.dev/badge/instructions/thibautbaissac/rails_ai_agents/agents-md/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.

Your own site · 80×15

<a href="https://agentmods.dev/instructions/thibautbaissac/rails_ai_agents/agents-md"><img src="https://agentmods.dev/badge/instructions/thibautbaissac/rails_ai_agents/agents-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 798 This file is loaded in full into every session.

When invoked 798 The same file — it is already loaded in full.

Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.

Origin original No closer match found in the catalogue.

Token cost

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	$0.00798	$0.00798
Opus 5.5	$0.00319	$0.00319
Sonnet 5.5	$0.00160	$0.00160
Haiku 4.5	$0.00080	$0.00080

Measured 2mo ago against content hash 700ab6ae2436, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

rails_ai_agents AGENTS.md 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 2mo 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.

AGENTS.md · 82 lines

How it starts

The opening of the file, as written. The whole thing — 82 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Project Configuration

Tech Stack

Ruby 3.3, Rails 8.1, PostgreSQL
Frontend: Hotwire (Turbo + Stimulus), Tailwind CSS 4, ViewComponent
Testing: RSpec, FactoryBot, Shoulda Matchers, Capybara
Auth: has_secure_password (Rails 8 built-in), Pundit (authorization)
Background Jobs: Solid Queue (database-backed, no Redis)
Caching: Solid Cache | WebSockets: Solid Cable
Assets: Propshaft + Import Maps (no Node.js)
Deployment: Kamal 2 + Thruster

Architecture

app/
  controllers/     # Thin. Delegates to services. Renders responses.
  models/          # Persistence: validations, associations, scopes, simple predicates.
  views/           # ERB markup only. No logic.
  services/        # Business logic. Orchestrates models, APIs, side effects.
  queries/         # Complex database queries. Returns relations or hashes.
  forms/           # Multi-model form objects.
  policies/        # Pundit authorization. Default deny.
  presenters/      # View formatting (SimpleDelegator).
  components/      # ViewComponents (reusable UI with tests).
  jobs/            # Background jobs (Solid Queue). Must be idempotent.
  mailers/         # Email delivery. Always HTML + text templates.

Key Commands

# Tests
bundle exec rspec                              # Full suite
bundle exec rspec spec/path/to_spec.rb         # Specific file
bundle exec rspec spec/path/to_spec.rb:25      # Specific line

# Linting
bundle exec rubocop -a                         # Auto-fix Ruby
bundle exec rubocop -a app/models/             # Specific directory

# Security
bin/brakeman --no-pager                        # Static analysis
bundle exec bundler-audit check --update       # Gem vulnerabilities

# Database
bin/rails db:migrate                           # Run migrations
bin/rails db:migrate:status                    # Check status
bin/rails console                              # Interactive console

Development Workflow

Read the full file on GitHub · 82 lines

Changes

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.

2mo ago First seen · 82 lines · 798 tokens per session scan A 700ab6ae2436

Subscribe to this mod's changes

rails_ai_agents AGENTS.md is an instructions file published in the GitHub repository ThibautBaissac/rails_ai_agents (672 stars, last pushed 5mo ago), licensed MIT. It adds 798 tokens to every session, about $0.0032 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.

Backend and APIs Databases PostgreSQL

rails_ai_agents AGENTS.md next to 6 instructions from other repositories
Mod	Type	Stars	Last push	Licence	Scan	Tokens	Works with
rails_ai_agents AGENTS.mdThibautBaissac/rails_ai_agents	Instructions file	672	5mo ago	MIT	A	798	Codex, OpenCode
vscode buildNext.instructions.mdmicrosoft/vscode	Instructions file	195k	yesterday	MIT	A	9,719	GitHub Copilot
next.js AGENTS.mdvercel/next.js	Instructions file	143k	today	MIT	A	7,461	Codex, OpenCode
langchain AGENTS.mdlangchain-ai/langchain	Instructions file	149k	yesterday	MIT	A	4,680	Codex, OpenCode
vscode oss-third-party-notices.instructions.mdmicrosoft/vscode	Instructions file	195k	yesterday	MIT	A	5,516	GitHub Copilot
vscode copilot-instructions.mdmicrosoft/vscode	Instructions file	195k	yesterday	MIT	A	3,093	GitHub Copilot
deepseek-harness AGENTS.mddeepseek-ai/deepseek-harness	Instructions file	274k	2d ago	MIT	A	4,313	Codex, OpenCode

rails_ai_agents: Instructions file for Codex