diff --git a/test/common/README.md b/test/common/README.md
index 0542c38bbcb419..f62ad2bb816441 100644
--- a/test/common/README.md
+++ b/test/common/README.md
@@ -4,15 +4,20 @@ This directory contains modules used to test the Node.js implementation.
 
 ## Table of Contents
 
+* [ArrayStream module](#arraystream-module)
 * [Benchmark module](#benchmark-module)
 * [Common module API](#common-module-api)
 * [Countdown module](#countdown-module)
 * [DNS module](#dns-module)
 * [Duplex pair helper](#duplex-pair-helper)
+* [Environment variables](#environment-variables)
 * [Fixtures module](#fixtures-module)
 * [Heap dump checker module](#heap-dump-checker-module)
+* [hijackstdio module](#hijackstdio-module)
 * [HTTP2 module](#http2-module)
 * [Internet module](#internet-module)
+* [ongc module](#ongc-module)
+* [Report module](#report-module)
 * [tick module](#tick-module)
 * [tmpdir module](#tmpdir-module)
 * [WPT module](#wpt-module)
@@ -495,6 +500,21 @@ which returns an object `{ clientSide, serverSide }` where each side is a
 
 There is no difference between client or server side beyond their names.
 
+## Environment variables
+
+The behavior of the Node.js test suite can be altered using the following
+environment variables.
+
+### NODE_SKIP_FLAG_CHECK
+
+If set, command line arguments passed to individual tests are not validated.
+
+### NODE_TEST_KNOWN_GLOBALS
+
+A comma-separated list of variables names that are appended to the global
+variable whitelist. Alternatively, if `NODE_TEST_KNOWN_GLOBALS` is set to `'0'`,
+global leak detection is disabled.
+
 ## Fixtures Module
 
 The `common/fixtures` module provides convenience methods for working with
@@ -780,6 +800,33 @@ a full `setImmediate()` invocation passes.
 `listener` is an object to make it easier to use a closure; the target object
 should not be in scope when `listener.ongc()` is created.
 
+## Report Module
+
+The `report` module provides helper functions for testing diagnostic reporting
+functionality.
+
+### findReports(pid, dir)
+
+* `pid` [<number>] Process ID to retrieve diagnostic report files for.
+* `dir` [<string>] Directory to search for diagnostic report files.
+* return [<Array>]
+
+Returns an array of diagnotic report file names found in `dir`. The files should
+have been generated by a process whose PID matches `pid`.
+
+### validate(report)
+
+* `report` [<string>] Diagnostic report file name to validate.
+
+Validates the schema of a diagnostic report file whose path is specified in
+`report`. If the report fails validation, an exception is thrown.
+
+### validateContent(data)
+
+* `data` [<string>] Contents of a diagnostic report file.
+
+Validates the schema of a diagnostic report whose content is specified in
+`data`. If the report fails validation, an exception is thrown.
 
 ## tick Module