modularization

modularization is a skill for Claude Code, Codex from rcosteira79/android-skills. It costs 114 tokens per session (353 once invoked), scanned A, original, MIT.

A set of Kotlin visibility rules for Android projects split into multiple modules, such as app, data, and feature modules. It helps decide whether code should be private, available within its module, or public to other modules.

In plain words
What is it for?
Use it when adding or changing classes, functions, properties, objects, or constants in a multi-module Android or Kotlin project. It guides visibility choices for interfaces, implementations, helpers, mappers, extensions, and UI state.
Why use it?
It prevents implementation details from becoming part of a module’s public interface by accident. This reduces unwanted dependencies and the need to keep internal code stable for other modules.

Skill for Claude CodeCodex

Part of the android-skills plugin — 21 skills shipped together

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/rcosteira79/android-skills/modularization
Any agent
npx skills add rcosteira79/android-skills --skill modularization
Clone the repo
git clone --depth 1 https://github.com/rcosteira79/android-skills

Made for: Claude Code, Codex.

Or install android-skills, the plugin that ships this one along with the rest of its 21 skills.

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 modularization

README.md
[![agentmods](https://agentmods.dev/badge/skills/rcosteira79/android-skills/modularization.svg)](https://agentmods.dev/skills/rcosteira79/android-skills/modularization)
Your own site
<a href="https://agentmods.dev/skills/rcosteira79/android-skills/modularization"><img src="https://agentmods.dev/badge/skills/rcosteira79/android-skills/modularization.svg" alt="Measured on agentmods" height="20"></a>
Per session 114 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 353 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 $0.00114 $0.00353
Opus 5 $0.00057 $0.00177
Sonnet 5 $0.00023 $0.00071
Haiku 4.5 $0.00011 $0.00035

Measured 3d ago against content hash 5cf427ce80a3, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

modularization 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 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.

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.

plugins/android-skills/skills/modularization/SKILL.md · 15 lines

What it actually says

Modularization

Declare everything at the lowest visibility that still compiles. Start private; widen to internal only when another file in the same module needs it; widen to public only when a different module actually consumes it. Kotlin defaults to public, and in a multi-module project that default is usually wrong — a public symbol joins the module's API surface: it leaks implementation across the boundary and you are then obliged to keep it stable.

  • Public interface as the module's API → the interface is public; its implementation class stays internal (DI-bound, never named from another module).
  • Mapper / helper / extension / constant / UI-state holder used only inside the module → internal (or private if a single file uses it). "Rendered by a composable in this module" does not require publicinternal is visible to the whole module.
  • Member used only within its class → private.

Widening a symbol to public is a decision, not a default: confirm a real cross-module consumer first.

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. 3d ago First seen · 15 lines · 114 tokens per session scan A 5cf427ce80a3

Subscribe to this mod's changes

modularization is a skill published in the GitHub repository rcosteira79/android-skills (136 stars, last pushed 9d ago), licensed MIT. It adds 114 tokens to every session and 353 once invoked, about $0.0006 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 2026-08-30.

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