What is serverless-mcp CLAUDE.md?

Project instructions for a TypeScript MCP server designed for serverless hosting, such as AWS Lambda. They document development, testing, building, linting, and the server's code structure.

Use them when developing tools, running tests and type checks, formatting code, linting, or building the server for deployment.

They give contributors the commands and conventions needed to change the project without breaking its build or checks.

How HeatherFlux/serverless-mcp configures Claude Code

Reuse

Borrowing it

Nothing to install: this file belongs to HeatherFlux/serverless-mcp. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file

curl -O https://raw.githubusercontent.com/HeatherFlux/serverless-mcp/main/CLAUDE.md

Clone the repo

git clone --depth 1 https://github.com/HeatherFlux/serverless-mcp

Made for: Claude Code.

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.

README.md

[![agentmods](https://agentmods.dev/badge/instructions/heatherflux/serverless-mcp/claude-md/github.svg)](https://agentmods.dev/instructions/heatherflux/serverless-mcp/claude-md)

Your own site

<a href="https://agentmods.dev/instructions/heatherflux/serverless-mcp/claude-md"><img src="https://agentmods.dev/badge/instructions/heatherflux/serverless-mcp/claude-md/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.

Your own site · 80×15

<a href="https://agentmods.dev/instructions/heatherflux/serverless-mcp/claude-md"><img src="https://agentmods.dev/badge/instructions/heatherflux/serverless-mcp/claude-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 723 This file is loaded in full into every session.

When invoked 723 The same file — it is already loaded in full.

Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.

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.

Model	Per session	Once invoked
Fable 5.1	$0.00723	$0.00723
Opus 5.5	$0.00289	$0.00289
Sonnet 5.5	$0.00145	$0.00145
Haiku 4.5	$0.00072	$0.00072

Measured 2mo ago against content hash 52f507703327, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

serverless-mcp 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 2mo 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.

CLAUDE.md · 77 lines

How it starts

The opening of the file, as written. The whole thing — 77 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.

Common Commands

Development

pnpm dev - Watch mode for development with tsx
pnpm test:watch - Run tests in watch mode with vitest

Testing

pnpm test - Run full test suite (vitest + typecheck + lint)
pnpm test:coverage - Run tests with coverage report
vitest run src/tools/provider.test.ts - Run specific test file
vitest run -t "test name" - Run specific test by name

Building

pnpm build:all - Build complete package (types + ESM)
pnpm build:types - Generate TypeScript declarations only
pnpm build:esm - Build ESM modules only
pnpm clean - Remove dist directory

Code Quality

pnpm lint - Run Biome linter
pnpm lint:fix - Auto-fix linting issues
pnpm format - Format code with Biome
pnpm typecheck - Run TypeScript type checking

Architecture Overview

This is a TypeScript implementation of the Model Context Protocol (MCP) with modular architecture optimized for serverless deployments, particularly AWS Lambda with streaming support.

Core Structure

The codebase follows a slice-based architecture where each MCP capability is isolated in its own module:

core/ - JSON-RPC protocol implementation and main McpServer orchestrator
prompts/ - Prompt template management with decorators and validation
resources/ - Resource providers with caching support
tools/ - Tool execution with middleware pipeline (timing, logging, rate limiting)
roots/ - File system boundary management
transports/ - Multiple transport layers (stdio, HTTP streaming, Lambda)
lambda/ - AWS Lambda-specific handler with streaming response support

Key Design Patterns

Provider Pattern: Each slice (tools, resources, prompts, roots) implements a provider interface that the McpServer consumes. Providers handle registration, validation, and execution of their respective capabilities.

Read the full file on GitHub · 77 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.

2mo ago First seen · 77 lines · 723 tokens per session scan A 52f507703327

Subscribe to this mod's changes

serverless-mcp CLAUDE.md is an instructions file published in the GitHub repository HeatherFlux/serverless-mcp (2 stars, last pushed 1y ago), licensed MIT. It adds 723 tokens to every session, about $0.0029 per session on Opus 5.5. 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 2026-08-31.

DevOps and cloud

serverless-mcp CLAUDE.md next to 6 instructions from other repositories
Mod	Type	Stars	Last push	Licence	Scan	Tokens	Works with
serverless-mcp CLAUDE.mdHeatherFlux/serverless-mcp	Instructions file	2	1y ago	MIT	A	723	Claude Code
vscode buildNext.instructions.mdmicrosoft/vscode	Instructions file	195k	yesterday	MIT	A	9,719	GitHub Copilot
next.js AGENTS.mdvercel/next.js	Instructions file	143k	yesterday	MIT	A	7,461	Codex, OpenCode
langchain AGENTS.mdlangchain-ai/langchain	Instructions file	149k	yesterday	MIT	A	4,680	Codex, OpenCode
vscode oss-third-party-notices.instructions.mdmicrosoft/vscode	Instructions file	195k	yesterday	MIT	A	5,516	GitHub Copilot
vscode copilot-instructions.mdmicrosoft/vscode	Instructions file	195k	yesterday	MIT	A	3,093	GitHub Copilot
deepseek-harness AGENTS.mddeepseek-ai/deepseek-harness	Instructions file	274k	2d ago	MIT	A	4,313	Codex, OpenCode

serverless-mcp: Instructions file for Claude Code