api-config

Overview

Configuration has two layers: core config (managed by the framework, env-driven) and server config (your own Zod schema for domain-specific env vars). Never merge them.

Import: AppConfig, config, parseConfig, resetConfig, ConfigSchema from @cyanheads/mcp-ts-core/config.

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Core config

Managed by @cyanheads/mcp-ts-core. Validated via Zod from environment variables. Uses a lazy proxy — parsing is deferred until the first property read.

Priority (highest to lowest):

1. name/version/title/websiteUrl/description/icons options passed to createApp() or createWorkerHandler()
2. Environment variables
3. package.json fields

Where package.json is read from: the application root — the nearest package.json at or above the process entry module (process.argv[1]), which is the served package on every launch path (npx, .mcpb, a client config naming dist/index.js), none of which run from the package root. The launching client's working directory is never the anchor: a stdio client starts the server from wherever it happens to be, so reading identity from there makes a server report a foreign project's name and version. When the entry module is a tool installed under the project's own node_modules and the process runs from that project — a test runner is the usual case — the project's manifest wins. With no manifest reachable, the framework's own identity is the fallback.

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Identity

Env Var	AppConfig field	Default	Notes
MCP_SERVER_NAME	mcpServerName	package.json name	Overrides package name
MCP_SERVER_VERSION	mcpServerVersion	package.json version	Overrides package version
MCP_SERVER_DESCRIPTION	mcpServerDescription	package.json description	Optional; createApp({ description }) wins when set
PACKAGE_NAME	pkg.name	package.json name	Rarely needed
PACKAGE_VERSION	pkg.version	package.json version	Rarely needed