diff --git a/lib/mocha.js b/lib/mocha.js
index 673dbec394..1700fe9ca7 100644
--- a/lib/mocha.js
+++ b/lib/mocha.js
@@ -8,7 +8,7 @@
 
 var escapeRe = require('escape-string-regexp');
 var path = require('path');
-var reporters = require('./reporters');
+var builtinReporters = require('./reporters');
 var utils = require('./utils');
 
 exports = module.exports = Mocha;
@@ -34,11 +34,10 @@ if (!process.browser) {
 exports.utils = utils;
 exports.interfaces = require('./interfaces');
 /**
- *
- * @memberof Mocha
  * @public
+ * @memberof Mocha
  */
-exports.reporters = reporters;
+exports.reporters = builtinReporters;
 exports.Runnable = require('./runnable');
 exports.Context = require('./context');
 /**
@@ -51,34 +50,46 @@ exports.Hook = require('./hook');
 exports.Test = require('./test');
 
 /**
- * Return image `name` path.
+ * Returns Growl image `name` path.
  *
  * @private
- * @param {string} name
- * @return {string}
+ * @param {string} name - Basename of associated Growl image.
+ * @return {string} Pathname to Growl image
  */
 function image(name) {
   return path.join(__dirname, '..', 'assets', 'growl', name + '.png');
 }
 
 /**
- * Set up mocha with `options`.
- *
- * Options:
- *
- *   - `ui` name "bdd", "tdd", "exports" etc
- *   - `reporter` reporter instance, defaults to `mocha.reporters.spec`
- *   - `globals` array of accepted globals
- *   - `timeout` timeout in milliseconds
- *   - `retries` number of times to retry failed tests
- *   - `bail` bail on the first test failure
- *   - `slow` milliseconds to wait before considering a test slow
- *   - `ignoreLeaks` ignore global leaks
- *   - `fullTrace` display the full stack-trace on failing
- *   - `grep` string or regexp to filter tests with
+ * Constructs a new Mocha instance with `options`.
  *
+ * @public
  * @class Mocha
- * @param {Object} options
+ * @param {Object} [options] - Settings object.
+ * @param {boolean} [options.allowUncaught] - Propagate uncaught errors?
+ * @param {boolean} [options.asyncOnly] - Force `done` callback or promise?
+ * @param {boolean} [options.bail] - Bail after first test failure?
+ * @param {boolean} [options.delay] - Delay root suite execution?
+ * @param {boolean} [options.enableTimeouts] - Enable timeouts?
+ * @param {string} [options.fgrep] - Test filter given string.
+ * @param {boolean} [options.forbidOnly] - Tests marked `only` fail the suite?
+ * @param {boolean} [options.forbidPending] - Pending tests fail the suite?
+ * @param {boolean} [options.fullStackTrace] - Full stacktrace upon failure?
+ * @param {string[]} [options.globals] - Variables expected in global scope.
+ * @param {RegExp|string} [options.grep] - Test filter given regular expression.
+ * @param {boolean} [options.growl] - Enable desktop notifications?
+ * @param {boolean} [options.hideDiff] - Suppress diffs from failures?
+ * @param {boolean} [options.ignoreLeaks] - Ignore global leaks?
+ * @param {boolean} [options.invert] - Invert test filter matches?
+ * @param {boolean} [options.noHighlighting] - Disable syntax highlighting?
+ * @param {string} [options.reporter] - Reporter name.
+ * @param {Object} [options.reporterOptions] - Reporter settings object.
+ * @param {number} [options.retries] - Number of times to retry failed tests.
+ * @param {number} [options.slow] - Slow threshold value.
+ * @param {number|string} [options.timeout] - Timeout threshold value.
+ * @param {string} [options.ui] - Interface name.
+ * @param {boolean} [options.useColors] - Color TTY output from reporter?
+ * @param {boolean} [options.useInlineDiffs] - Use inline diffs?
  */
 function Mocha(options) {
   options = options || {};
@@ -110,11 +121,13 @@ function Mocha(options) {
 }
 
 /**
- * Enable or disable bailing on the first failure.
+ * Enables or disables bailing on the first failure.
  *
  * @public
- * @api public
- * @param {boolean} [bail]
+ * @see {@link https://mochajs.org/#-b---bail|CLI option}
+ * @param {boolean} [bail=true] - Whether to bail on first error.
+ * @returns {Mocha} this
+ * @chainable
  */
 Mocha.prototype.bail = function(bail) {
   if (!arguments.length) {
@@ -125,11 +138,17 @@ Mocha.prototype.bail = function(bail) {
 };
 
 /**
- * Add test `file`.
+ * @summary
+ * Adds `file` to be loaded for execution.
+ *
+ * @description
+ * Useful for generic setup code that must be included within test suite.
  *
  * @public
- * @api public
- * @param {string} file
+ * @see {@link https://mochajs.org/#--file-file|CLI option}
+ * @param {string} file - Pathname of file to be loaded.
+ * @returns {Mocha} this
+ * @chainable
  */
 Mocha.prototype.addFile = function(file) {
   this.files.push(file);
@@ -137,14 +156,20 @@ Mocha.prototype.addFile = function(file) {
 };
 
 /**
- * Set reporter to `reporter`, defaults to "spec".
+ * Sets reporter to `reporter`, defaults to "spec".
  *
  * @public
- * @param {String|Function} reporter name or constructor
- * @param {Object} reporterOptions optional options
- * @api public
- * @param {string|Function} reporter name or constructor
- * @param {Object} reporterOptions optional options
+ * @see {@link https://mochajs.org/#-r---reporter-name|CLI option}
+ * @see {@link https://mochajs.org/#reporters|Reporters}
+ * @param {String|Function} reporter - Reporter name or constructor.
+ * @param {Object} [reporterOptions] - Options used to configure the reporter.
+ * @returns {Mocha} this
+ * @chainable
+ * @throws {Error} if requested reporter cannot be loaded
+ * @example
+ *
+ * // Use XUnit reporter and direct its output to file
+ * mocha.reporter('xunit', { output: '/path/to/testspec.xunit.xml' });
  */
 Mocha.prototype.reporter = function(reporter, reporterOptions) {
   if (typeof reporter === 'function') {
@@ -153,8 +178,8 @@ Mocha.prototype.reporter = function(reporter, reporterOptions) {
     reporter = reporter || 'spec';
     var _reporter;
     // Try to load a built-in reporter.
-    if (reporters[reporter]) {
-      _reporter = reporters[reporter];
+    if (builtinReporters[reporter]) {
+      _reporter = builtinReporters[reporter];
     }
     // Try to load reporters from process.cwd() and node_modules
     if (!_reporter) {
@@ -199,10 +224,15 @@ Mocha.prototype.reporter = function(reporter, reporterOptions) {
 };
 
 /**
- * Set test UI `name`, defaults to "bdd".
+ * Sets test UI `name`, defaults to "bdd".
+ *
  * @public
- * @api public
- * @param {string} bdd
+ * @see {@link https://mochajs.org/#-u---ui-name|CLI option}
+ * @see {@link https://mochajs.org/#interfaces|Interface DSLs}
+ * @param {string} [name=bdd] - Interface name.
+ * @returns {Mocha} this
+ * @chainable
+ * @throws {Error} if requested interface cannot be loaded
  */
 Mocha.prototype.ui = function(name) {
   name = name || 'bdd';
@@ -237,9 +267,16 @@ Mocha.prototype.ui = function(name) {
 };
 
 /**
- * Load registered files.
+ * @summary
+ * Loads `files` prior to execution.
+ *
+ * @description
+ * The implementation relies on Node's `require` to execute
+ * the test interface functions and will be subject to its cache.
  *
- * @api private
+ * @private
+ * @see {@link Mocha#addFile}
+ * @param {Function} [fn] - Callback invoked upon completion.
  */
 Mocha.prototype.loadFiles = function(fn) {
   var self = this;
@@ -254,9 +291,12 @@ Mocha.prototype.loadFiles = function(fn) {
 };
 
 /**
- * Enable growl support.
+ * Implements desktop notifications using a pseudo-reporter.
  *
- * @api private
+ * @private
+ * @see {@link Mocha#growl}
+ * @param {Object} runner - Runner instance.
+ * @param {Object} reporter - Reporter instance.
  */
 Mocha.prototype._growl = function(runner, reporter) {
   var notify = require('growl');
@@ -277,26 +317,55 @@ Mocha.prototype._growl = function(runner, reporter) {
 };
 
 /**
- * Escape string and add it to grep as a regexp.
+ * Sets `grep` filter after escaping RegExp special characters.
  *
  * @public
- * @api public
- * @param str
- * @returns {Mocha}
+ * @see {@link Mocha#grep}
+ * @param {string} str - Value to be converted to a regexp.
+ * @returns {Mocha} this
+ * @chainable
+ * @example
+ *
+ * // Select tests whose full title begins with `"foo"` followed by a period
+ * mocha.fgrep('foo.');
  */
 Mocha.prototype.fgrep = function(str) {
   return this.grep(new RegExp(escapeRe(str)));
 };
 
 /**
- * Add regexp to grep, if `re` is a string it is escaped.
+ * @summary
+ * Sets `grep` filter used to select specific tests for execution.
+ *
+ * @description
+ * If `re` is a regexp-like string, it will be converted to regexp.
+ * The regexp is tested against the full title of each test (i.e., the
+ * name of the test preceded by titles of each its ancestral suites).
+ * As such, using an <em>exact-match</em> fixed pattern against the
+ * test name itself will not yield any matches.
+ * <br>
+ * <strong>Previous filter value will be overwritten on each call!</strong>
  *
  * @public
- * @param {RegExp|String} re
- * @return {Mocha}
- * @api public
- * @param {RegExp|string} re
- * @return {Mocha}
+ * @see {@link https://mochajs.org/#-g---grep-pattern|CLI option}
+ * @see {@link Mocha#fgrep}
+ * @see {@link Mocha#invert}
+ * @param {RegExp|String} re - Regular expression used to select tests.
+ * @return {Mocha} this
+ * @chainable
+ * @example
+ *
+ * // Select tests whose full title contains `"match"`, ignoring case
+ * mocha.grep(/match/i);
+ * @example
+ *
+ * // Same as above but with regexp-like string argument
+ * mocha.grep('/match/i');
+ * @example
+ *
+ * // ## Anti-example
+ * // Given embedded test `it('only-this-test')`...
+ * mocha.grep('/^only-this-test$/');    // NO! Use `.only()` to do this!
  */
 Mocha.prototype.grep = function(re) {
   if (utils.isString(re)) {
@@ -308,12 +377,18 @@ Mocha.prototype.grep = function(re) {
   }
   return this;
 };
+
 /**
- * Invert `.grep()` matches.
+ * Inverts `grep` matches.
  *
  * @public
- * @return {Mocha}
- * @api public
+ * @see {@link Mocha#grep}
+ * @return {Mocha} this
+ * @chainable
+ * @example
+ *
+ * // Select tests whose full title does *not* contain `"match"`, ignoring case
+ * mocha.grep(/match/i).invert();
  */
 Mocha.prototype.invert = function() {
   this.options.invert = true;
@@ -321,26 +396,31 @@ Mocha.prototype.invert = function() {
 };
 
 /**
- * Ignore global leaks.
+ * Enables or disables ignoring global leaks.
  *
  * @public
- * @param {Boolean} ignore
- * @return {Mocha}
- * @api public
- * @param {boolean} ignore
- * @return {Mocha}
- */
-Mocha.prototype.ignoreLeaks = function(ignore) {
-  this.options.ignoreLeaks = Boolean(ignore);
+ * @see {@link Mocha#checkLeaks}
+ * @param {boolean} ignoreLeaks - Whether to ignore global leaks.
+ * @return {Mocha} this
+ * @chainable
+ * @example
+ *
+ * // Ignore global leaks
+ * mocha.ignoreLeaks(true);
+ */
+Mocha.prototype.ignoreLeaks = function(ignoreLeaks) {
+  this.options.ignoreLeaks = Boolean(ignoreLeaks);
   return this;
 };
 
 /**
- * Enable global leak checking.
+ * Enables checking for global variables leaked while running tests.
  *
- * @return {Mocha}
- * @api public
  * @public
+ * @see {@link https://mochajs.org/#--check-leaks|CLI option}
+ * @see {@link Mocha#ignoreLeaks}
+ * @return {Mocha} this
+ * @chainable
  */
 Mocha.prototype.checkLeaks = function() {
   this.options.ignoreLeaks = false;
@@ -348,11 +428,11 @@ Mocha.prototype.checkLeaks = function() {
 };
 
 /**
- * Display long stack-trace on failing
+ * Displays full stack trace upon test failure.
  *
- * @return {Mocha}
- * @api public
  * @public
+ * @return {Mocha} this
+ * @chainable
  */
 Mocha.prototype.fullTrace = function() {
   this.options.fullStackTrace = true;
@@ -360,11 +440,12 @@ Mocha.prototype.fullTrace = function() {
 };
 
 /**
- * Enable growl support.
+ * Enables desktop notification support.
  *
- * @return {Mocha}
- * @api public
  * @public
+ * @see {@link Mocha#_growl}
+ * @return {Mocha} this
+ * @chainable
  */
 Mocha.prototype.growl = function() {
   this.options.growl = true;
@@ -372,14 +453,18 @@ Mocha.prototype.growl = function() {
 };
 
 /**
- * Ignore `globals` array or string.
+ * Specifies whitelist of variable names to be expected in global scope.
  *
- * @param {Array|String} globals
- * @return {Mocha}
- * @api public
  * @public
- * @param {Array|string} globals
- * @return {Mocha}
+ * @see {@link https://mochajs.org/#--globals-names|CLI option}
+ * @see {@link Mocha#checkLeaks}
+ * @param {String[]|String} globals - Accepted global variable name(s).
+ * @return {Mocha} this
+ * @chainable
+ * @example
+ *
+ * // Specify variables to be expected in global scope
+ * mocha.globals(['jQuery', 'MyLib']);
  */
 Mocha.prototype.globals = function(globals) {
   this.options.globals = (this.options.globals || []).concat(globals);
@@ -387,14 +472,12 @@ Mocha.prototype.globals = function(globals) {
 };
 
 /**
- * Emit color output.
+ * Enables or disables TTY color output by screen-oriented reporters.
  *
- * @param {Boolean} colors
- * @return {Mocha}
- * @api public
  * @public
- * @param {boolean} colors
- * @return {Mocha}
+ * @param {boolean} colors - Whether to enable color output.
+ * @return {Mocha} this
+ * @chainable
  */
 Mocha.prototype.useColors = function(colors) {
   if (colors !== undefined) {
@@ -404,14 +487,13 @@ Mocha.prototype.useColors = function(colors) {
 };
 
 /**
- * Use inline diffs rather than +/-.
+ * Determines if reporter should use inline diffs (rather than +/-)
+ * in test failure output.
  *
- * @param {Boolean} inlineDiffs
- * @return {Mocha}
- * @api public
  * @public
- * @param {boolean} inlineDiffs
- * @return {Mocha}
+ * @param {boolean} inlineDiffs - Whether to use inline diffs.
+ * @return {Mocha} this
+ * @chainable
  */
 Mocha.prototype.useInlineDiffs = function(inlineDiffs) {
   this.options.useInlineDiffs = inlineDiffs !== undefined && inlineDiffs;
@@ -419,14 +501,12 @@ Mocha.prototype.useInlineDiffs = function(inlineDiffs) {
 };
 
 /**
- * Do not show diffs at all.
+ * Determines if reporter should include diffs in test failure output.
  *
- * @param {Boolean} hideDiff
- * @return {Mocha}
- * @api public
  * @public
- * @param {boolean} hideDiff
- * @return {Mocha}
+ * @param {boolean} hideDiff - Whether to hide diffs.
+ * @return {Mocha} this
+ * @chainable
  */
 Mocha.prototype.hideDiff = function(hideDiff) {
   this.options.hideDiff = hideDiff !== undefined && hideDiff;
@@ -434,27 +514,47 @@ Mocha.prototype.hideDiff = function(hideDiff) {
 };
 
 /**
- * Set the timeout in milliseconds.
+ * @summary
+ * Sets timeout threshold value.
+ *
+ * @description
+ * A string argument can use shorthand (such as "2s") and will be converted.
+ * If the value is `0`, timeouts will be disabled.
  *
- * @param {Number} timeout
- * @return {Mocha}
- * @api public
  * @public
- * @param {number} timeout
- * @return {Mocha}
+ * @see {@link https://mochajs.org/#-t---timeout-ms|CLI option}
+ * @see {@link https://mochajs.org/#--no-timeouts|CLI option}
+ * @see {@link https://mochajs.org/#timeouts|Timeouts}
+ * @see {@link Mocha#enableTimeouts}
+ * @param {number|string} msecs - Timeout threshold value.
+ * @return {Mocha} this
+ * @chainable
+ * @example
+ *
+ * // Sets timeout to one second
+ * mocha.timeout(1000);
+ * @example
+ *
+ * // Same as above but using string argument
+ * mocha.timeout('1s');
  */
-Mocha.prototype.timeout = function(timeout) {
-  this.suite.timeout(timeout);
+Mocha.prototype.timeout = function(msecs) {
+  this.suite.timeout(msecs);
   return this;
 };
 
 /**
- * Set the number of times to retry failed tests.
+ * Sets the number of times to retry failed tests.
  *
- * @param {Number} retry times
- * @return {Mocha}
- * @api public
  * @public
+ * @see {@link https://mochajs.org/#retry-tests|Retry Tests}
+ * @param {number} retry - Number of times to retry failed tests.
+ * @return {Mocha} this
+ * @chainable
+ * @example
+ *
+ * // Allow any failed test to retry one more time
+ * mocha.retries(1);
  */
 Mocha.prototype.retries = function(n) {
   this.suite.retries(n);
@@ -462,43 +562,50 @@ Mocha.prototype.retries = function(n) {
 };
 
 /**
- * Set slowness threshold in milliseconds.
+ * Sets slowness threshold value.
  *
- * @param {Number} slow
- * @return {Mocha}
- * @api public
  * @public
- * @param {number} slow
- * @return {Mocha}
+ * @see {@link https://mochajs.org/#-s---slow-ms|CLI option}
+ * @param {number} msecs - Slowness threshold value.
+ * @return {Mocha} this
+ * @chainable
+ * @example
+ *
+ * // Sets "slow" threshold to half a second
+ * mocha.slow(500);
+ * @example
+ *
+ * // Same as above but using string argument
+ * mocha.slow('0.5s');
  */
-Mocha.prototype.slow = function(slow) {
-  this.suite.slow(slow);
+Mocha.prototype.slow = function(msecs) {
+  this.suite.slow(msecs);
   return this;
 };
 
 /**
- * Enable timeouts.
+ * Enables or disables timeouts.
  *
- * @param {Boolean} enabled
- * @return {Mocha}
- * @api public
  * @public
- * @param {boolean} enabled
- * @return {Mocha}
+ * @see {@link https://mochajs.org/#-t---timeout-ms|CLI option}
+ * @see {@link https://mochajs.org/#--no-timeouts|CLI option}
+ * @param {boolean} enableTimeouts - Whether to enable timeouts.
+ * @return {Mocha} this
+ * @chainable
  */
-Mocha.prototype.enableTimeouts = function(enabled) {
+Mocha.prototype.enableTimeouts = function(enableTimeouts) {
   this.suite.enableTimeouts(
-    arguments.length && enabled !== undefined ? enabled : true
+    arguments.length && enableTimeouts !== undefined ? enableTimeouts : true
   );
   return this;
 };
 
 /**
- * Makes all tests async (accepting a callback)
+ * Forces all tests to either accept a `done` callback or return a promise.
  *
- * @return {Mocha}
- * @api public
  * @public
+ * @return {Mocha} this
+ * @chainable
  */
 Mocha.prototype.asyncOnly = function() {
   this.options.asyncOnly = true;
@@ -506,10 +613,11 @@ Mocha.prototype.asyncOnly = function() {
 };
 
 /**
- * Disable syntax highlighting (in browser).
+ * Disables syntax highlighting (in browser).
  *
- * @api public
  * @public
+ * @return {Mocha} this
+ * @chainable
  */
 Mocha.prototype.noHighlighting = function() {
   this.options.noHighlighting = true;
@@ -517,11 +625,11 @@ Mocha.prototype.noHighlighting = function() {
 };
 
 /**
- * Enable uncaught errors to propagate (in browser).
+ * Enables uncaught errors to propagate (in browser).
  *
- * @return {Mocha}
- * @api public
  * @public
+ * @return {Mocha} this
+ * @chainable
  */
 Mocha.prototype.allowUncaught = function() {
   this.options.allowUncaught = true;
@@ -529,8 +637,16 @@ Mocha.prototype.allowUncaught = function() {
 };
 
 /**
- * Delay root suite execution.
- * @returns {Mocha}
+ * @summary
+ * Delays root suite execution.
+ *
+ * @description
+ * Used to perform asynch operations before any suites are run.
+ *
+ * @public
+ * @see {@link https://mochajs.org/#delayed-root-suite|delayed root suite}
+ * @returns {Mocha} this
+ * @chainable
  */
 Mocha.prototype.delay = function delay() {
   this.options.delay = true;
@@ -538,8 +654,11 @@ Mocha.prototype.delay = function delay() {
 };
 
 /**
- * Tests marked only fail the suite
- * @returns {Mocha}
+ * Causes tests marked `only` to fail the suite.
+ *
+ * @public
+ * @returns {Mocha} this
+ * @chainable
  */
 Mocha.prototype.forbidOnly = function() {
   this.options.forbidOnly = true;
@@ -547,8 +666,11 @@ Mocha.prototype.forbidOnly = function() {
 };
 
 /**
- * Pending tests and tests marked skip fail the suite
- * @returns {Mocha}
+ * Causes pending tests and tests marked `skip` to fail the suite.
+ *
+ * @public
+ * @returns {Mocha} this
+ * @chainable
  */
 Mocha.prototype.forbidPending = function() {
   this.options.forbidPending = true;
@@ -556,20 +678,26 @@ Mocha.prototype.forbidPending = function() {
 };
 
 /**
- * Run tests and invoke `fn()` when complete.
+ * Callback to be invoked when test execution is complete.
+ *
+ * @callback DoneCB
+ * @param {number} failures - Number of failures that occurred.
+ */
+
+/**
+ * @summary
+ * Runs tests and invokes `fn()` when complete.
  *
- * Note that `loadFiles` relies on Node's `require` to execute
- * the test interface functions and will be subject to the
- * cache - if the files are already in the `require` cache,
- * they will effectively be skipped. Therefore, to run tests
- * multiple times or to run tests in files that are already
- * in the `require` cache, make sure to clear them from the
- * cache first in whichever manner best suits your needs.
+ * @description
+ * To run tests multiple times (or to run tests in files that are
+ * already in the `require` cache), make sure to clear them from
+ * the cache first!
  *
- * @api public
  * @public
- * @param {Function} fn
- * @return {Runner}
+ * @see {@link Mocha#loadFiles}
+ * @see {@link Runner#run}
+ * @param {DoneCB} [fn] - Callback invoked when test execution completed.
+ * @return {Runner} runner instance
  */
 Mocha.prototype.run = function(fn) {
   if (this.files.length) {