diff --git a/core/tests/vm-benchmark/harness/src/instruction_counter.rs b/core/tests/vm-benchmark/harness/src/instruction_counter.rs
index bff42defc50d..b52678ca20da 100644
--- a/core/tests/vm-benchmark/harness/src/instruction_counter.rs
+++ b/core/tests/vm-benchmark/harness/src/instruction_counter.rs
@@ -11,6 +11,7 @@ pub struct InstructionCounter {
     output: Rc<RefCell<usize>>,
 }
 
+/// A tracer that counts the number of instructions executed by the VM.
 impl InstructionCounter {
     pub fn new(output: Rc<RefCell<usize>>) -> Self {
         Self { count: 0, output }