Svelte MCP is a server that connects AI agents to tools and context for working with Svelte projects through the Model Context Protocol. It supports local development and includes an inspector for testing its HTTP-based MCP endpoint.
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.
npx agentmods add instructions/sveltejs/ai-tools/claude-mdgit clone --depth 1 https://github.com/sveltejs/ai-toolsWrote 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.
[](https://agentmods.dev/instructions/sveltejs/ai-tools/claude-md)<a href="https://agentmods.dev/instructions/sveltejs/ai-tools/claude-md"><img src="https://agentmods.dev/badge/instructions/sveltejs/ai-tools/claude-md.svg" alt="Measured on agentmods" height="20"></a>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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5 | $0.00922 | $0.00922 |
| Opus 5 | $0.00461 | $0.00461 |
| Sonnet 5 | $0.00184 | $0.00184 |
| Haiku 4.5 | $0.00092 | $0.00092 |
Grade A, and why
ai-tools CLAUDE.md 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 5d 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.
How it starts
The opening of the file, as written. The whole thing — 101 lines — stays where its author put it; the contents beside it link to each section on GitHub.
CLAUDE.md
This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
Development Commands
This is a Svelte MCP (Model Context Protocol) server implementation that includes both SvelteKit web interface and MCP server functionality.
Setup
pnpm i
cp .env.example .env
# Set the VOYAGE_API_KEY for embeddings support in .env
pnpm dev
Common Commands
pnpm dev- Start SvelteKit development serverpnpm build- Build the application for productionpnpm start- Run the MCP server (Node.js entry point)pnpm check- Run Svelte type checkingpnpm check:watch- Run type checking in watch modepnpm lint- Run prettier check and eslintpnpm format- Format code with prettierpnpm test- Run unit tests with vitestpnpm test:watch- Run tests in watch mode
Database Commands (Drizzle ORM)
pnpm db:push- Push schema changes to databasepnpm db:generate- Generate migration filespnpm db:migrate- Run migrationspnpm db:studio- Open Drizzle Studio
Architecture
MCP Server Implementation
The core MCP server is implemented in src/lib/mcp/index.ts using the tmcp library with:
- Transport Layers: Both HTTP (
HttpTransport) and STDIO (StdioTransport) support - Schema Validation: Uses Valibot with
ValibotJsonSchemaAdapter - Main Tool:
svelte-autofixer- analyzes Svelte code and provides suggestions/fixes
Code Analysis Engine
Located in src/lib/server/analyze/:
- Parser (
parse.ts): Usessvelte-eslint-parserand TypeScript parser to analyze Svelte components - Scope Analysis: Tracks variables, references, and scopes across the AST
- Rune Detection: Identifies Svelte 5 runes (
$state,$effect,$derived, etc.)
Autofixer System
- Autofixers (
src/lib/mcp/autofixers.ts): Visitor pattern implementations for code analysis - Walker Utility (
src/lib/index.ts): Enhanced AST walking with visitor mixing capabilities - Current Autofixer:
assign_in_effect- detects assignments to$statevariables inside$effectblocks
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.
- 5d ago First seen · 101 lines · 922 tokens per session scan A 1707a6375458
ai-tools CLAUDE.md is an instructions file published in the GitHub repository sveltejs/ai-tools (316 stars, last pushed yesterday), licensed MIT. It adds 922 tokens to every session, about $0.0046 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.
Other instructions, from other repositories
vscode buildNext.instructions.md
Working notes and architecture documentation for the new esbuild-based build system in build/next. Use when making changes to the new build pipeline (transpile/bundle commands, NLS plugin, source-map handling, resource copying, or self-hosting watch tasks).
spec-kit AGENTS.md
AGENTS.md instructions for github/spec-kit, covering agents.md, about spec kit and specify, quickstart — add a new integration in 5 steps, integration architecture and integrationmanifest — file tracking.
codex AGENTS.md
AGENTS.md instructions for openai/codex, covering rust/codex-rs, the codex-core crate, code review rules, crate api surface and model visible context.
langchain AGENTS.md
AGENTS.md instructions for langchain-ai/langchain, covering global development guidelines for the langchain monorepo, corridor security analysis, project architecture and context, monorepo structure and development tools & commands.
vscode oss-third-party-notices.instructions.md
Instructions for microsoft/vscode, covering vs code oss third-party-notices pipeline, architecture, pipeline flow in ci, applying the notice (cutover) and fallback chain (never fail the build).
next.js AGENTS.md
Instructions for vercel/next.js, covering next.js development guide, codebase structure, monorepo overview, core package: packages/next and other important packages.