diff --git a/onnxruntime/core/providers/coreml/builders/impl/base_op_builder.cc b/onnxruntime/core/providers/coreml/builders/impl/base_op_builder.cc
index f267dc755135..25d7890faeba 100644
--- a/onnxruntime/core/providers/coreml/builders/impl/base_op_builder.cc
+++ b/onnxruntime/core/providers/coreml/builders/impl/base_op_builder.cc
@@ -13,6 +13,8 @@ using namespace CoreML::Specification;
 namespace onnxruntime {
 namespace coreml {
 
+// Once all ops are supportted FP16, we can remove it. Before that, we keep a set of ops to
+// filter suppported ones.
 static std::set<const std::string> Float16Ops = {
     "Add", "Mul", "Sub", "Div", "Pow", "Sqrt", "Reciprocal",
     "Sigmoid", "Tanh", "Relu", "LeakyRelu", "Concat", "GridSample", "GlobalAveragePool",
@@ -110,11 +112,13 @@ bool BaseOpBuilder::IsInputDtypeSupport(const Node& node, size_t idx, const OpBu
     return true;
   }
 
+// only support MLProgram for FP16
 #if defined(COREML_ENABLE_MLPROGRAM)
   if (input_params.create_mlprogram && input_type == ONNX_NAMESPACE::TensorProto_DataType_FLOAT16 && Float16Ops.count(node.OpType())) {
     return true;
   }
 #endif
+
   LOGS(logger, VERBOSE) << "[" << node.OpType() << "] Input type: [" << input_type << "] is not currently supported";
   return false;
 }
diff --git a/onnxruntime/core/providers/coreml/builders/impl/base_op_builder.h b/onnxruntime/core/providers/coreml/builders/impl/base_op_builder.h
index a2cbef6dd57d..153ae841b238 100644
--- a/onnxruntime/core/providers/coreml/builders/impl/base_op_builder.h
+++ b/onnxruntime/core/providers/coreml/builders/impl/base_op_builder.h
@@ -32,7 +32,7 @@ class BaseOpBuilder : public IOpBuilder {
       : allow_empty_tensor_as_input_(allow_empty_tensor_as_input) {
   }
 
-  // currently we only support float
+  // currently we support float/float16
   static bool IsInputDtypeSupport(const Node& node, size_t idx, const OpBuilderInputParams& input_params,
                                   const logging::Logger& logger);
 
diff --git a/onnxruntime/core/providers/coreml/builders/impl/unary_op_builder.cc b/onnxruntime/core/providers/coreml/builders/impl/unary_op_builder.cc
index aa3060d62686..e8a138aa4979 100644
--- a/onnxruntime/core/providers/coreml/builders/impl/unary_op_builder.cc
+++ b/onnxruntime/core/providers/coreml/builders/impl/unary_op_builder.cc
@@ -27,7 +27,6 @@ Status UnaryOpBuilder::AddToModelBuilderImpl(ModelBuilder& model_builder, const
   if (model_builder.CreateMLProgram()) {
     using namespace CoreML::Specification::MILSpec;
 
-    // https://apple.github.io/coremltools/source/coremltools.converters.mil.mil.ops.defs.html#module-coremltools.converters.mil.mil.ops.defs.iOS15.elementwise_binary
     std::string_view coreml_op_type;
     if (op_type == "Sqrt") {
       coreml_op_type = "sqrt";