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 skills/ag0os/rails-dev-plugin/rails-caching-patternsnpx skills add ag0os/rails-dev-plugin --skill rails-caching-patternsgit 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/skills/ag0os/rails-dev-plugin/rails-caching-patterns)<a href="https://agentmods.dev/skills/ag0os/rails-dev-plugin/rails-caching-patterns"><img src="https://agentmods.dev/badge/skills/ag0os/rails-dev-plugin/rails-caching-patterns.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 | $0.00146 | $0.01542 |
| Opus 5 | $0.00073 | $0.00771 |
| Sonnet 5 | $0.00029 | $0.00308 |
| Haiku 4.5 | $0.00015 | $0.00154 |
Grade A, and why
rails-caching-patterns scanned grade A with 1 finding 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 3d 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.
Makes network callslowCapability
Not a fault in itself. Listed so you know the mod talks to something, and to what.
Rails.cache.fetch(stats_cache_key, expires_in: 1.day) do How it starts
The opening of the file, as written. The whole thing — 174 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Rails Caching Patterns
Analyze and recommend caching strategies across all layers of a Rails application.
Follow standard Rails conventions for basic cache helper, Rails.cache.fetch, stale?/fresh_when, and expires_in. Focus on the opinionated patterns below.
See patterns.md for detailed code examples.
Quick Reference
| Pattern | Use When |
|---|---|
Russian doll + touch: true |
Nested associations — inner updates bust outer caches |
race_condition_ttl |
High-traffic keys — prevents cache stampede on expiry |
fetch_multi |
Multiple cache reads — one round-trip instead of N |
Collection caching (cached: true) |
Rendering collections — uses read_multi internally |
| Solid Cache vs Redis | Match the configured store; default Solid Cache unless Redis is already in the stack |
| Composite cache keys | Varying by user, locale, or version |
Choosing a Cache Store
The cache store is an orthogonal project fact, not an architecture choice. If the project already configures one, match it (project-conventions fingerprint). For a new choice, pick by what is already in the stack:
| Store | Use when | Why |
|---|---|---|
config.cache_store = :solid_cache_store |
No Redis in the stack | No external deps, database-backed, Rails 8 default |
config.cache_store = :redis_cache_store, { url: ENV["REDIS_URL"] } |
Redis already running (Sidekiq, ActionCable) | Reuse existing infrastructure |
:memory_store |
Development | Toggle with bin/rails dev:cache |
Core Principles
- Cache the expensive thing closest to where it's used: HTTP > fragment > low-level
- Key-based expiration over manual invalidation: Let
cache_key_with_versionchange when data changes - Measure before caching: Use
rack-mini-profileror server timing — don't cache what isn't slow - Russian doll from outside in:
touch: truepropagates changes up the association chain - Never cache user-specific content in shared caches without varying the key
What ships with it
1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
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.
- 3d ago First seen · 174 lines · 146 tokens per session scan A 3e4183779e59
rails-caching-patterns is a skill published in the GitHub repository ag0os/rails-dev-plugin (5 stars, last pushed 3mo ago), licensed MIT. It adds 146 tokens to every session and 1,542 once invoked, about $0.0007 per session on Opus 5. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.
Other skills, from other repositories
systematic-debugging
Use when encountering any bug, test failure, or unexpected behavior, before proposing fixes.
brainstorming
You MUST use this before any creative work - creating features, building components, adding functionality, or modifying behavior. Explores user intent, requirements and design before implementation.
auto-perf-optimize
Run agent-driven VS Code performance or memory investigations. Use when asked to launch Code OSS, automate a VS Code scenario, run the Chat memory smoke runner, capture renderer heap snapshots, take workflow screenshots, compare run summaries, or drive a repeatable scenario before heap-snapshot analysis.
chat-perf
Run chat perf benchmarks and memory leak checks against the local dev build or any published VS Code version. Use when investigating chat rendering regressions, validating perf-sensitive changes to chat UI, or checking for memory leaks in the chat response pipeline.
chat-pet-sprite-creation
Use when creating or changing VS Code chat pet sprite art, sprite sheets, state animations, eye treatments, Stable/Insiders variants, or pet transitions under src/vs/workbench/contrib/chat/browser/widget/media/chatPet.
cpu-profile-analysis
Analyze V8/Chrome CPU profiles (.cpuprofile) and DevTools trace files (Trace-.json). Use when: profiling performance, investigating slow functions, comparing code paths, finding bottlenecks, analyzing timeToRequest, understanding call trees from sampling profiler data, analyzing layout/paint/rendering, investigating…