cache-engineering

cache-engineering is a skill for Claude Code, Codex from Dankosik/go-service-template-rest. It costs 28 tokens per session (215 once invoked), scanned A, original, MIT.

A reference skill for deciding whether and how to use a cache, which is a temporary copy kept to avoid repeatedly retrieving the original data. It covers cache keys, freshness, filling, invalidation, failures, and rollout proof.

In plain words
What is it for?
It is for cache design decisions, freshness and invalidation rules, concurrent fills, hot keys, outages, migrations, and rollout checks.
Why use it?
It helps define when cached data is trustworthy, who updates it, and what happens when the cache is stale or unavailable.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one.

Install

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.

agentmods
npx agentmods add skills/dankosik/go-service-template-rest/cache-engineering
Any agent
npx skills add Dankosik/go-service-template-rest --skill cache-engineering
Clone the repo
git clone --depth 1 https://github.com/Dankosik/go-service-template-rest

Made for: Claude Code, Codex.

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.

agentmods badge for cache-engineering

README.md
[![agentmods](https://agentmods.dev/badge/skills/dankosik/go-service-template-rest/cache-engineering.svg)](https://agentmods.dev/skills/dankosik/go-service-template-rest/cache-engineering)
Your own site
<a href="https://agentmods.dev/skills/dankosik/go-service-template-rest/cache-engineering"><img src="https://agentmods.dev/badge/skills/dankosik/go-service-template-rest/cache-engineering.svg" alt="Measured on agentmods" height="20"></a>
Per session 28 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 215 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00028 $0.00215
Opus 5 $0.00014 $0.00108
Sonnet 5 $0.00006 $0.00043
Haiku 4.5 $0.00003 $0.00021

Measured 6d ago against content hash 6dba74d3ccac, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

cache-engineering 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 6d 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.

docs/universal-disciplines/cache-engineering/SKILL.md · 24 lines

What it actually says

Cache Engineering

Use only after the active phase identifies a cache-specific decision. Inherit its authority, artifact, review, proof, output, and completion contract; do not select design, diagnosis, implementation, review, or production-action mode.

Core invariant: a cache is a bounded copy with explicit authority, key scope, freshness, fill and invalidation ownership, degraded behavior, and a falsifier. Reject a cache whose measured value does not justify that complexity.

Load one branch:

  • whether caching should exist -> value.md;
  • value, key, freshness, or invalidation contract -> contract.md;
  • concurrent fill, hot key, outage, or layer-specific behavior -> runtime.md;
  • migration, rollout, or proof -> rollout-proof.md.
Files

What ships with it

4 files 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.

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.

  1. 6d ago First seen · 24 lines · 28 tokens per session scan A 6dba74d3ccac

Subscribe to this mod's changes

cache-engineering is a skill published in the GitHub repository Dankosik/go-service-template-rest (6 stars, last pushed yesterday), licensed MIT. It adds 28 tokens to every session and 215 once invoked, about $0.0001 per session on Opus 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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