Active Storage Validations is a Ruby gem for adding validation rules to files attached through Rails Active Storage. Rails developers use it to check whether uploaded images, videos, audio files, PDFs, and other attachments meet requirements such as type, size, dimensions, duration, or quantity.
Borrowing it
Nothing to install: this file belongs to igorkasyanchuk/active_storage_validations. 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/igorkasyanchuk/active_storage_validations/master/AGENTS.mdgit clone --depth 1 https://github.com/igorkasyanchuk/active_storage_validationsWrote 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/igorkasyanchuk/active_storage_validations/agents-md)<a href="https://agentmods.dev/instructions/igorkasyanchuk/active_storage_validations/agents-md"><img src="https://agentmods.dev/badge/instructions/igorkasyanchuk/active_storage_validations/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.
<a href="https://agentmods.dev/instructions/igorkasyanchuk/active_storage_validations/agents-md"><img src="https://agentmods.dev/badge/instructions/igorkasyanchuk/active_storage_validations/agents-md.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 | $0.04710 | $0.04710 |
| Opus 5.5 | $0.01884 | $0.01884 |
| Sonnet 5.5 | $0.00942 | $0.00942 |
| Haiku 4.5 | $0.00471 | $0.00471 |
Grade A, and why
active_storage_validations 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 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 — 276 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Active Storage Validations — Guide for AI Coding Agents
This is the codebase of the active_storage_validations gem: Active Model validators for Rails Active Storage attachments (presence, content type, size, dimensions, duration, aspect ratio, PDF pages, etc.).
It is a gem, not a Rails application. Specs boot a Combustion dummy app under test/dummy/.
Architecture Overview
lib/active_storage_validations.rb # Entry point + infer_file_field_accept / command_timeout config
lib/active_storage_validations/
*_validator.rb # Validators (ActiveModel::EachValidator)
base_comparison_validator.rb # Shared comparison options (<, <=, >, >=, between, equal_to)
asv_attachable_adapter.rb # Per-type wrappers for Blob / UploadedFile / Hash / File / Pathname / signed id
shared/asv_*.rb # Shared concerns used by validators
analyzer/ # Media metadata extractors (image/video/audio/pdf)
analyzer/content_type_analyzer/ # Spoofing sniffers: File + Magika backends
extensors/ # Blob metadata + Marcel helpers
matchers/ # Opt-in RSpec/Minitest matchers (consumer-facing)
form_builder.rb # Infers HTML accept from content_type validators
railtie.rb / engine.rb # Rails integration + locale loading
config/locales/*.yml # I18n error messages (all locales must stay in sync)
spec/ # RSpec suite (validators, matchers, analyzers, form_builder, integration)
test/dummy/ # Combustion Rails app + per-validator models
gemfiles/ # Per-Rails-version Bundler Gemfiles (not Appraisal)
benchmark/ # Optional ips / require suite (not shipped in the gem)
docs/upgrade_to_*.md # Upgrade guides
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 Changed · +2 lines · +169 tokens per session 8cb980576a80
- 2mo ago Changed · +27 lines · +958 tokens per session f3bf9e3a0811
- 2mo ago First seen · 247 lines · 3,583 tokens per session scan A b6d6866981b2
active_storage_validations AGENTS.md is an instructions file published in the GitHub repository igorkasyanchuk/active_storage_validations (1,193 stars, last pushed 5d ago), licensed MIT. It adds 4,710 tokens to every session, about $0.0188 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 2026-08-30.
active_storage_validations AGENTS.md compared with instructions from other repositories
| Mod | Type | Stars | Last push | Licence | Scan | Tokens | Works with |
|---|---|---|---|---|---|---|---|
| active_storage_validations AGENTS.mdigorkasyanchuk/active_storage_validations | Instructions file | 1.2k | 5d ago | MIT | A | 4,710 | 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 | today | 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 |