aosp-appendices

aosp-appendices is a skill for Claude Code, Codex from aospbooks/aosp-internal-book. It costs 132 tokens per session (493 once invoked), scanned A, original, Apache-2.0.

A reference guide to Android Open Source Project internals, including important source-file paths, technical terms, Kotlin and public APIs, and Android 16-to-17 changes. AOSP is the publicly available source code that forms the basis of Android.

In plain words
What is it for?
Use it to look up AOSP file locations, explain terms such as Treble or APEX, understand Kotlin's role, and review documented Android 16-to-17 updates.
Why use it?
Android source code contains many specialized names and is spread across numerous subsystems. The guide helps developers find relevant files and understand those terms and changes.

Skill for Claude CodeCodex

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

Good fit Use it to look up AOSP file locations, explain terms such as Treble or APEX, understand Kotlin's role, and review documented Android 16-to-17 updates.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/aospbooks/aosp-internal-book/appendices
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.

Any agent
npx skills add aospbooks/aosp-internal-book --skill appendices
Clone the repo
git clone --depth 1 https://github.com/aospbooks/aosp-internal-book

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 aosp-appendices

README.md
[![agentmods](https://agentmods.dev/badge/skills/aospbooks/aosp-internal-book/appendices/github.svg)](https://agentmods.dev/skills/aospbooks/aosp-internal-book/appendices)
Your own site
<a href="https://agentmods.dev/skills/aospbooks/aosp-internal-book/appendices"><img src="https://agentmods.dev/badge/skills/aospbooks/aosp-internal-book/appendices/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.

agentmods 80×15 button for aosp-appendices

Your own site · 80×15
<a href="https://agentmods.dev/skills/aospbooks/aosp-internal-book/appendices"><img src="https://agentmods.dev/badge/skills/aospbooks/aosp-internal-book/appendices.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 132 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 493 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • NVIDIA SkillSpector pass 7 Sept 2026
How audits are shown
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 $0.00132 $0.00493
Opus 5 $0.00066 $0.00246
Sonnet 5 $0.00026 $0.00099
Haiku 4.5 $0.00013 $0.00049

Measured 9d ago against content hash c2a3c5a1d32f, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade A, and why

aosp-appendices 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 9d 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.

Origin

Copies of this mod

1 near-identical copy found in the catalogue:

agents/_content/parts/appendices/SKILL.md · 36 lines

What it actually says

AOSP Internals — Appendices

Reference material: a per-chapter index of key source files, a glossary of AOSP-specific terms, a note on the Kotlin/public-API asymmetry, and the Android 16→17 changelog.

Files in this skill

  • A-appendix-key-files.md — per-chapter table of the most important AOSP source files (sorted ascending by chapter number)
  • B-appendix-glossary.md — definitions of AOSP-specific acronyms and terms
  • C-appendix-kotlin-public-api.md — why Kotlin is heavily used in AOSP services yet absent from the android.* public API
  • D-appendix-android-17-updates.md — important platform changes from Android 16 to Android 17, by subsystem, grounded in the 16→17 changeset and verified against AOSP 17 source

When to load which file

  • Need a specific source file path for a subsystem → A-appendix-key-files.md
  • Need a definition of an AOSP acronym (Treble, VINTF, GKI, APEX, AIDL, HIDL, etc.) → B-appendix-glossary.md
  • Question about Kotlin's role in AOSP vs. the public API → C-appendix-kotlin-public-api.md
  • What changed from Android 16 to Android 17 → D-appendix-android-17-updates.md
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. 9d ago First seen · 36 lines · 132 tokens per session scan A c2a3c5a1d32f

Subscribe to this mod's changes

aosp-appendices is a skill published in the GitHub repository aospbooks/aosp-internal-book (131 stars, last pushed 10d ago), licensed Apache-2.0. It adds 132 tokens to every session and 493 once invoked, about $0.0007 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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