diff --git a/src/main/java/org/scijava/command/CommandModuleItem.java b/src/main/java/org/scijava/command/CommandModuleItem.java
@@ -145,7 +145,14 @@ public T getMaximumValue() {

	@Override
	public Number getStepSize() {
-		return tValue(getParameter().stepSize(), Number.class);
	}

	@Override

diff --git a/src/test/java/org/scijava/command/InvalidCommandTest.java b/src/test/java/org/scijava/command/InvalidCommandTest.java
@@ -71,6 +71,10 @@ public void testValid() {
		final List<ValidityProblem> problems = info.getProblems();
		assertNotNull(problems);
		assertEquals(0, problems.size());
	}

	@Test
@@ -101,7 +105,7 @@ public void testInvalid() {
	@Plugin(type = Command.class)
	public static class ValidCommand implements Command {

-		@Parameter
		private double x;

		@Parameter(type = ItemIO.OUTPUT)