The Programmable City — a design-first MCP server over New York City government: 67 agencies, ten common government-process skills, cross-agency prompts and resources, backed by the NYC Modernization reference example data.

A robust, ES3 compatible, "has own property" predicate.

ES Object-related atoms: Object, ToObject, RequireObjectCoercible

Is this value a JS Date object? This module works cross-realm/iframe, and despite ES6 @@toStringTag.

Is this value negative zero? === will lie to you

Is this value a JS String object or primitive? This module works cross-realm/iframe, and despite ES6 @@toStringTag.

ECMAScript “ToPrimitive” algorithm. Provides ES5 and ES2015 versions.

Is this value an ES BigInt?

Determine if a function is a native async function.

A simple cache for a few of the JS Error constructors.

Determine if a value is an ES6 Symbol or not.

Get the ArrayBuffer out of a DataView, robustly.

Is this value a JS Map? This module works cross-realm/iframe, and despite ES6 @@toStringTag.

Determine if the current node version supports the `--preserve-symlinks` flag.

Human-friendly process signals

JSON.parse with context information on error

Determine if the JS environment has `Symbol.toStringTag` support. Supports spec, or shams.

Library for generating pseudo-random values that follow known patterns and can be used in various ways (e.g., as example data, for testing purposes, etc.).

concatenative mapdashery

Native Abstractions for Node.js: C++ header for Node 0.8 -> 26 compatibility