next.js/packages/next/src/compiled/client-only/package.json

{
  "name": "client-only",
  "description": "This is a marker package to indicate that a module can only be used in Client Components.",
  "keywords": [
    "react"
  ],
  "version": "0.0.1",
  "homepage": "https://reactjs.org/",
  "bugs": "https://github.com/facebook/react/issues",
  "license": "MIT",
  "files": ["index.js", "error.js"],
  "main": "index.js",
  "exports": {
    ".": {
      "react-server": "./error.js",
      "default": "./index.js"
    }
  }
}