what is svelte-instinct fr?

svelte-instinct is a skill for Claude Code that teaches the AI assistant how to write correct Svelte code, whether a project uses Svelte 4 or the newer Svelte 5. Without guidance, an AI coding assistant often mixes up old and new Svelte syntax or borrows patterns from React or Vue, which breaks reactivity. The README shows this directly: without the skill, clicking a button updates a local counter but a value that should be calculated from it, labeled Double, stays stuck at zero. With the skill active, Claude Code correctly uses Svelte 5's newer reactive primitives, and the calculated value updates in real time as expected. The skill installs with a single command that adds it to a Claude Code agent globally, using the skills package manager. Once installed, it automatically detects which version of Svelte a project is using by reading the package.json file or by analyzing the existing .svelte files in the codebase, then applies the right set of rules. For Svelte 4 projects it enforces the standard let, export let and reactive dollar colon syntax, while for Svelte 5 projects it enforces the newer Runes system, meaning state, derived and props declarations, along with Snippets and the newer onclick style event handlers instead of the older on:click syntax. Beyond the basics, the skill also covers more advanced patterns, including two way bindings with the bindable rune, proper cleanup of side effects inside the effect rune, and storing reactive state in .svelte.js or .svelte.ts files rather than the older store based approach. If a project does not have a package.json at its root, or a developer wants to force a specific version for just one file, a special comment can be placed at the top of that .svelte file to explicitly declare whether it should be treated as Svelte 4 or Svelte 5.