diff --git a/test/parallel/test-fs-readfile-empty.js b/test/parallel/test-fs-readfile-empty.js
index bbc2e9c81d6251..21f99fc6be24ba 100644
--- a/test/parallel/test-fs-readfile-empty.js
+++ b/test/parallel/test-fs-readfile-empty.js
@@ -21,6 +21,9 @@
 
 'use strict';
 require('../common');
+
+// Trivial test of fs.readFile on an empty file.
+
 const assert = require('assert');
 const fs = require('fs');
 const fixtures = require('../common/fixtures');
diff --git a/test/parallel/test-fs-readfile-error.js b/test/parallel/test-fs-readfile-error.js
index e7c52f19a83d1c..616760b06695a1 100644
--- a/test/parallel/test-fs-readfile-error.js
+++ b/test/parallel/test-fs-readfile-error.js
@@ -21,6 +21,9 @@
 
 'use strict';
 const common = require('../common');
+
+// Test that fs.readFile fails correctly on a non-existent file.
+
 // `fs.readFile('/')` does not fail on FreeBSD, because you can open and read
 // the directory there.
 if (common.isFreeBSD)
diff --git a/test/parallel/test-fs-readfile-fd.js b/test/parallel/test-fs-readfile-fd.js
index 7881666cadb31a..7458af7b2e53af 100644
--- a/test/parallel/test-fs-readfile-fd.js
+++ b/test/parallel/test-fs-readfile-fd.js
@@ -1,5 +1,8 @@
 'use strict';
 require('../common');
+
+// Test fs.readFile using a file descriptor.
+
 const fixtures = require('../common/fixtures');
 const assert = require('assert');
 const fs = require('fs');
diff --git a/test/parallel/test-fs-readfile-unlink.js b/test/parallel/test-fs-readfile-unlink.js
index abcbed7ad5df53..9ec2e849bee19f 100644
--- a/test/parallel/test-fs-readfile-unlink.js
+++ b/test/parallel/test-fs-readfile-unlink.js
@@ -21,6 +21,9 @@
 
 'use strict';
 const common = require('../common');
+
+// Test that unlink succeeds immediately after readFile completes.
+
 const assert = require('assert');
 const fs = require('fs');
 const path = require('path');
diff --git a/test/parallel/test-fs-readfile-zero-byte-liar.js b/test/parallel/test-fs-readfile-zero-byte-liar.js
index 625438e7c68c88..ec0b9cf6922c8c 100644
--- a/test/parallel/test-fs-readfile-zero-byte-liar.js
+++ b/test/parallel/test-fs-readfile-zero-byte-liar.js
@@ -21,6 +21,9 @@
 
 'use strict';
 const common = require('../common');
+
+// Test that readFile works even when stat returns size 0.
+
 const assert = require('assert');
 const fs = require('fs');