diff --git a/index.js b/index.js
index 5da6eb42..904f366d 100644
--- a/index.js
+++ b/index.js
@@ -107,7 +107,7 @@ function createHarness(conf_) {
 	var only = false;
 	test.only = function () {
 		if (only) { throw new Error('there can only be one only test'); }
-		if (conf_.noOnly) { throw new Error('`only` tests are prohibited'); }
+		if (conf_ && conf_.noOnly) { throw new Error('`only` tests are prohibited'); }
 		only = true;
 		var t = test.apply(null, arguments);
 		results.only(t);
diff --git a/test/exposed-harness.js b/test/exposed-harness.js
index cb8b6019..fc375c29 100644
--- a/test/exposed-harness.js
+++ b/test/exposed-harness.js
@@ -3,12 +3,10 @@
 var tape = require('../');
 var tap = require('tap');
 
-tap.test('main harness object is exposed', function (assert) {
+tap.test('main harness object is exposed', function (tt) {
+	tt.equal(typeof tape.getHarness, 'function', 'tape.getHarness is a function');
 
-	assert.equal(typeof tape.getHarness, 'function', 'tape.getHarness is a function');
-
-	assert.equal(tape.getHarness()._results.pass, 0);
-
-	assert.end();
+	tt.equal(tape.getHarness()._results.pass, 0);
 
+	tt.end();
 });
diff --git a/test/only.js b/test/only.js
index 3302fb20..eb28ac65 100644
--- a/test/only.js
+++ b/test/only.js
@@ -46,3 +46,11 @@ tap.test('tape only test', function (tt) {
 		t.end();
 	});
 });
+
+tap.test('created harness with no conf', function (tt) {
+	var harness = tape.createHarness();
+
+	tt.doesNotThrow(function () { harness.only({ skip: true }); }, 'harness.only does not throw with omitted harness conf arg');
+
+	tt.end();
+});