Initial import with skill sheet working

node_modules/module-error/README.md

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+# module-error
+
+**Create errors with `code` and `cause` properties. Simple and extensible.**
+
+[![npm status](http://img.shields.io/npm/v/module-error.svg)](https://www.npmjs.org/package/module-error)
+[![node](https://img.shields.io/node/v/module-error.svg)](https://www.npmjs.org/package/module-error)
+[![Test](https://img.shields.io/github/workflow/status/vweevers/module-error/Test?label=test)](https://github.com/vweevers/module-error/actions/workflows/test.yml)
+[![Standard](https://img.shields.io/badge/standard-informational?logo=javascript&logoColor=fff)](https://standardjs.com)
+[![Common Changelog](https://common-changelog.org/badge.svg)](https://common-changelog.org)
+
+## Usage
+
+Works like a regular `Error` constructor but adds an options argument (as [`proposal-error-cause`](https://github.com/tc39/proposal-error-cause) does).
+
+```js
+const ModuleError = require('module-error')
+
+throw new ModuleError('Message goes here', {
+  code: 'EXAMPLE_NOT_FOUND'
+})
+```
+
+The primary purpose of `ModuleError` is to define a `code` property on the error object following Node.js conventions. It should be set to an uppercase string that uniquely identifies a situation, prefixed with the name of your module (or a collection of modules) to prevent conflicts.
+
+The output looks like this in Node.js (some stack frames omitted for brevity):
+
+```
+ModuleError: Message goes here
+    at Object.<anonymous> (/home/app/example.js:5:7)
+    at node:internal/main/run_main_module:17:47 {
+  code: 'EXAMPLE_NOT_FOUND'
+}
+```
+
+The benefit of error codes is that messages can be changed without a semver-major release because your [semver](https://semver.org) contract will be on the codes. Codes can be reused across related modules while allowing individual modules to customize messages. I also prefer it over `instanceof MyError` logic because codes work cross-realm and when a tree of `node_modules` contains multiple versions of a module.
+
+To wrap another error:
+
+```js
+try {
+  JSON.parse(await fs.readFile('state.json'))
+} catch (err) {
+  throw new ModuleError('Could not load state', {
+    code: 'EXAMPLE_INVALID_STATE',
+    cause: err
+  })
+}
+```
+
+If for convenience you want to create subclasses with prepared codes:
+
+```js
+class NotFoundError extends ModuleError {
+  constructor(message, options) {
+    super(message, { ...options, code: 'EXAMPLE_NOT_FOUND' })
+  }
+}
+```
+
+Then you can do:
+
+```js
+throw new NotFoundError('Message goes here')
+```
+
+Under Node.js the stack trace will be adjusted accordingly, to skip the frame containing your error constructor.
+
+## API
+
+### `ModuleError(message, [options])`
+
+Constructor to create an error with the provided `message` string. Options:
+
+- `code` (string): if provided, define a `code` property with this value.
+- `cause` (Error): if provided, define a `cause` property with this value. Unlike the spec of [`proposal-error-cause`](https://github.com/tc39/proposal-error-cause) the property is enumerable so that Node.js (v16 at the time of writing) will print it. Firefox prints it regardless, Chromium doesn't yet.
+- `expected`: if truthy, define a `expected` property with value `true`. This is useful for command line interfaces to differentiate unexpected errors from e.g. invalid user input. A pattern I like to follow is to print only an error message if `err.expected` is true and no `--verbose` flag was provided. Otherwise print the full stack.
+- `transient`: if truthy, define a `transient` property with value `true`. This communicates to users that the operation that caused the error may be retried. See also [`transient-error`](https://github.com/vweevers/transient-error) to mark existing errors as transient.
+
+## Install
+
+With [npm](https://npmjs.org) do:
+
+```
+npm install module-error
+```
+
+## License
+
+[MIT](LICENSE)