understanding-hot-reload-limits

understanding-hot-reload-limits is a skill for Claude Code, Codex from skydoves/compose-performance-skills. It costs 174 tokens per session (2,422 once invoked), scanned A, original, Apache-2.0.

Guidance for understanding which Kotlin and Jetpack Compose changes can update through Compose HotSwan and which require a full incremental rebuild. Hot reload updates running code without restarting the whole app.

In plain words
What is it for?
Use it when a hot-reload session falls back to a rebuild, when a code change does not reload, or when planning the order of refactoring and implementation work.
Why use it?
It explains why changes such as new fields, changed signatures, constructors, or interfaces leave the fast path, helping developers plan edits around slower rebuilds.

Skill for Claude CodeCodex

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

Good fit Use it when a hot-reload session falls back to a rebuild, when a code change does not reload, or when planning the order of refactoring and implementation work.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/skydoves/compose-performance-skills/understanding-hot-reload-limits
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 skydoves/compose-performance-skills --skill understanding-hot-reload-limits
Clone the repo
git clone --depth 1 https://github.com/skydoves/compose-performance-skills

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 understanding-hot-reload-limits

README.md
[![agentmods](https://agentmods.dev/badge/skills/skydoves/compose-performance-skills/understanding-hot-reload-limits/github.svg)](https://agentmods.dev/skills/skydoves/compose-performance-skills/understanding-hot-reload-limits)
Your own site
<a href="https://agentmods.dev/skills/skydoves/compose-performance-skills/understanding-hot-reload-limits"><img src="https://agentmods.dev/badge/skills/skydoves/compose-performance-skills/understanding-hot-reload-limits/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 understanding-hot-reload-limits

Your own site · 80×15
<a href="https://agentmods.dev/skills/skydoves/compose-performance-skills/understanding-hot-reload-limits"><img src="https://agentmods.dev/badge/skills/skydoves/compose-performance-skills/understanding-hot-reload-limits.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 174 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,422 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 warn 7 Sept 2026
SkillSpector: 1 finding, up to medium

These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →

  • medium Excessive Agency · line 172
    Skill enables autonomous high-impact decisions without human-in-the-loop verification. Critical operations (destructive commands, financial transactions, data deletion) should require explicit user confirmation.
    Fix: Add human-in-the-loop confirmation for destructive, irreversible, or high-impact operations. Never auto-execute commands that modify files, send data, or alter system state.
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 $0.00174 $0.02422
Opus 5 $0.00087 $0.01211
Sonnet 5 $0.00035 $0.00484
Haiku 4.5 $0.00017 $0.00242

Measured 10d ago against content hash 07d592502380, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade A, and why

understanding-hot-reload-limits 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 10d 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.

hot-reload/understanding-hot-reload-limits/SKILL.md · 192 lines

How it starts

The opening of the file, as written. The whole thing — 192 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Understanding Hot Reload Limits: stay inside the fast path

Android Runtime (ART) enforces strict rules for class redefinition: a redefined class must have an identical schema (fields, method signatures, interfaces) as the previous version. Only method bodies are mutable at runtime. HotSwan automatically detects schema changes and falls back to a full incremental build, so failures are not silent. Knowing the boundary in advance is what keeps an iteration loop sub-second instead of multi-second.

When to use this skill

  • The developer asks "why did this trigger a full rebuild?", "why isn't this hot reloading?", or "what does HotSwan support?".
  • A PR review surfaces a refactor (parameter change, constructor change, interface extraction, new resource id) that would push a hot-reload session into a rebuild.
  • The developer is planning a session and wants to order edits so the slow ones happen at the end.
  • The developer reports an inline fun change that "didn't reload" and is debugging.

When NOT to use this skill

  • Setup or first-run troubleshooting. See ../setting-up-compose-hotswan/SKILL.md.
  • Pure state-preservation question (the reload happened but state was lost). See the state-preservation sibling skill.
  • Configuration of the AI iteration loop or MCP server. See the AI-loop sibling skill.

Prerequisites

  • HotSwan installed and verified per ../setting-up-compose-hotswan/SKILL.md (tool window status WATCHING, body-only edit reloads in under one second).
  • Familiarity with the Kotlin compiler's distinction between method-body changes and class-schema changes.

Boundary tables

Hot-reloadable (no rebuild)

Change Notes
Composable function body text, colors, modifiers, layout, control flow inside the function
Non-composable function body ViewModel methods, mappers, utilities, repositories
Adding a new composable same file or new file
Reordering composables HotSwan 1.2.0+
Resource value changes strings.xml value, colors.xml value, dimens.xml value
Extension functions including suspend, including vararg
Adding data class properties API 30+ only
Numeric, string, float literal patches compiled separately for fastest reload

Read the full file on GitHub · 192 lines

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. 10d ago First seen · 192 lines · 174 tokens per session scan A 07d592502380

Subscribe to this mod's changes

understanding-hot-reload-limits is a skill published in the GitHub repository skydoves/compose-performance-skills (500 stars, last pushed 2mo ago), licensed Apache-2.0. It adds 174 tokens to every session and 2,422 once invoked, about $0.0009 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.

Related

Other skills, from other repositories

claude-android-ninja

Build and migrate Android apps with Kotlin, Jetpack Compose, MVVM, Hilt, Room 3 (KSP, SQLiteDriver, Flow/suspend DAOs), Navigation3, and multi-module Gradle. Use for new projects or modules, Compose screens and ViewModels, Room 3 and RemoteMediator, API 37 / targetSdk migration, Play Integrity client wiring…

Drjacky/claude-android-ninja · 123 tokens

compose-animations

Use when writing or reviewing Jetpack Compose motion: visibility enter/exit, animating one property toward a target, color or size transitions, multiple properties from one state, switching composable content, or choosing between AnimatedVisibility, animateAsState, rememberTransition, AnimatedContent, and Crossfade.

chrisbanes/skills · 64 tokens

compose-focus-navigation

Use when writing or reviewing Jetpack Compose UI for TV, keyboard, desktop, accessibility focus, D-pad navigation, FocusRequester, focusProperties, key events, or initial focus behavior.

chrisbanes/skills · 41 tokens

kotlin-android

Use when building or fixing a native Android app in Kotlin and Jetpack Compose on the UDF layered architecture — ViewModel/StateFlow, Hilt, Room, Retrofit, coroutines, type-safe Navigation, and the Gradle/AGP surface. NOT shared Android and iOS UI from one Kotlin codebase (that is compose-multiplatform).

ericrisco/rsc-harness · 78 tokens

compose-side-effects

Use when writing or reviewing Jetpack Compose code with LaunchedEffect, DisposableEffect, SideEffect, rememberCoroutineScope, rememberUpdatedState, snapshotFlow, snackbar, navigation, focus requests, analytics, or event Flow collection.

ashtanko/compose-android-template · 49 tokens

deliver-android-feature

Implement an Android feature from a specification or acceptance criteria through architecture, production code, formatting, unit tests, JVM integration tests, local Compose behavior tests, screenshot matrices, managed-device integration tests, end-to-end coverage, and final verification. Use when adding or…

ashtanko/compose-android-template · 82 tokens