Borrowing it
Nothing to install: this file belongs to beel-collab/presets.dev. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/beel-collab/presets.dev/main/release/rails/native/copilot/.github/instructions/rails.instructions.mdgit clone --depth 1 https://github.com/beel-collab/presets.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/instructions/beel-collab/presets.dev/rails)<a href="https://agentmods.dev/instructions/beel-collab/presets.dev/rails"><img src="https://agentmods.dev/badge/instructions/beel-collab/presets.dev/rails/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/instructions/beel-collab/presets.dev/rails"><img src="https://agentmods.dev/badge/instructions/beel-collab/presets.dev/rails.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 | $0.00699 | $0.00699 |
| Opus 5.5 | $0.00280 | $0.00280 |
| Sonnet 5.5 | $0.00140 | $0.00140 |
| Haiku 4.5 | $0.00070 | $0.00070 |
Grade A, and why
presets.dev rails.instructions.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 today.
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.
Rails Copilot Instructions: Models, Strong Params and Jobs
Path-specific Copilot instructions for Rails. They apply through applyTo and leave .github/copilot-instructions.md in place.
Updated for Rails 8.1.4.1, Nov 2026
Do not upgrade dependencies or the framework version unless the task asks.
Rails 8.1.4.1 is the current 8.1 security release. Stay on the version in the Gemfile. 8.1's job continuations, structured events, and local CI are available when the app is already on 8.1. Read an existing model and controller before you add one.
Project shape
A controller authorizes, permits parameters, and calls a model or a service object the app already uses. Fat controllers that contain queries and mailers are not the pattern to extend. Views do not query.
Strong parameters list the keys. permit! is a bug on a public action. A nested attribute is permitted only when the user may set it.
Models and queries
Validations protect invariants. A database unique index backs a uniqueness validation. Associations that a page walks are included or preloaded. A bullet or a query-count test is how you see an N+1. An unindexed foreign key on a big table is a review.
A callback that hides a write is hard to test. Prefer an explicit method when the project does not already use that callback.
Jobs
Passing an Active Record instance to a job is normal. GlobalID stores the model name and id, and the job loads the record again when it runs. Do not tell the author to pass only ids when the app already passes records.
A retry can run the same side effect twice. A continuation resumes interrupted work. It does not make a charge or a mail idempotent. Guard those effects with a key or a state check the app already uses. Structured events follow the logger the app already configured.
Security and tests
authorize or the app's policy runs before update and destroy. A missing check is not saved by a hidden button. CSRF stays on. Do not skip authenticity tokens for a browser form.
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.
- today First seen · 64 lines · 699 tokens per session scan A eec1cc718486
presets.dev rails.instructions.md is an instructions file published in the GitHub repository beel-collab/presets.dev (3 stars, last pushed yesterday), licensed MIT. It adds 699 tokens to every session, about $0.0028 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 2026-11-13.
presets.dev rails.instructions.md compared with instructions from other repositories
| Mod | Type | Stars | Last push | Licence | Scan | Tokens | Works with |
|---|---|---|---|---|---|---|---|
| presets.dev rails.instructions.mdbeel-collab/presets.dev | Instructions file | 3 | yesterday | MIT | A | 699 | GitHub Copilot |
| vscode buildNext.instructions.mdmicrosoft/vscode | Instructions file | 195k | today | MIT | A | 9,719 | GitHub Copilot |
| next.js AGENTS.mdvercel/next.js | Instructions file | 143k | today | MIT | A | 7,461 | Codex, OpenCode |
| vscode oss-third-party-notices.instructions.mdmicrosoft/vscode | Instructions file | 195k | today | MIT | A | 5,685 | GitHub Copilot |
| langchain AGENTS.mdlangchain-ai/langchain | Instructions file | 149k | today | MIT | A | 4,680 | Codex, OpenCode |
| vscode copilot-instructions.mdmicrosoft/vscode | Instructions file | 195k | today | MIT | A | 3,086 | GitHub Copilot |
| deepseek-harness AGENTS.mddeepseek-ai/deepseek-harness | Instructions file | 280k | 2d ago | MIT | A | 4,325 | Codex, OpenCode |