diff --git a/expander_compiler/src/frontend/api.rs b/expander_compiler/src/frontend/api.rs
index 1277620..8c7df53 100644
--- a/expander_compiler/src/frontend/api.rs
+++ b/expander_compiler/src/frontend/api.rs
@@ -20,7 +20,7 @@ pub trait BasicAPI<C: Config> {
     binary_op!(or);
     binary_op!(and);
 
-    fn display(&self, _x: impl ToVariableOrValue<C::CircuitField>) {}
+    fn display(&self, _label: &str, _x: impl ToVariableOrValue<C::CircuitField>) {}
     fn div(
         &mut self,
         x: impl ToVariableOrValue<C::CircuitField>,
@@ -78,15 +78,7 @@ pub trait UnconstrainedAPI<C: Config> {
     binary_op!(unconstrained_bit_xor);
 }
 
-// DebugAPI is used for debugging purposes
-// Only DebugBuilder will implement functions in this trait, other builders will panic
-pub trait DebugAPI<C: Config> {
-    fn value_of(&self, x: impl ToVariableOrValue<C::CircuitField>) -> C::CircuitField;
-}
-
-pub trait RootAPI<C: Config>:
-    Sized + BasicAPI<C> + UnconstrainedAPI<C> + DebugAPI<C> + 'static
-{
+pub trait RootAPI<C: Config>: Sized + BasicAPI<C> + UnconstrainedAPI<C> + 'static {
     fn memorized_simple_call<F: Fn(&mut Self, &Vec<Variable>) -> Vec<Variable> + 'static>(
         &mut self,
         f: F,
diff --git a/expander_compiler/src/frontend/builder.rs b/expander_compiler/src/frontend/builder.rs
index 3fc8b2e..2027c51 100644
--- a/expander_compiler/src/frontend/builder.rs
+++ b/expander_compiler/src/frontend/builder.rs
@@ -17,7 +17,7 @@ use crate::{
     utils::function_id::get_function_id,
 };
 
-use super::api::{BasicAPI, DebugAPI, RootAPI, UnconstrainedAPI};
+use super::api::{BasicAPI, RootAPI, UnconstrainedAPI};
 
 pub struct Builder<C: Config> {
     instructions: Vec<SourceInstruction<C>>,
@@ -447,12 +447,6 @@ impl<C: Config> RootAPI<C> for RootBuilder<C> {
     }
 }
 
-impl<C: Config> DebugAPI<C> for RootBuilder<C> {
-    fn value_of(&self, _x: impl ToVariableOrValue<C::CircuitField>) -> C::CircuitField {
-        panic!("ValueOf is not supported in non-debug mode");
-    }
-}
-
 impl<C: Config> RootBuilder<C> {
     pub fn new(
         num_inputs: usize,
diff --git a/expander_compiler/src/frontend/debug.rs b/expander_compiler/src/frontend/debug.rs
index 85885c0..85334f5 100644
--- a/expander_compiler/src/frontend/debug.rs
+++ b/expander_compiler/src/frontend/debug.rs
@@ -10,7 +10,7 @@ use crate::{
 };
 
 use super::{
-    api::{BasicAPI, DebugAPI, RootAPI, UnconstrainedAPI},
+    api::{BasicAPI, RootAPI, UnconstrainedAPI},
     builder::{get_variable_id, new_variable, ToVariableOrValue, VariableOrValue},
     Variable,
 };
@@ -20,9 +20,9 @@ pub struct DebugBuilder<C: Config> {
 }
 
 impl<C: Config> BasicAPI<C> for DebugBuilder<C> {
-    fn display(&self, x: impl ToVariableOrValue<<C as Config>::CircuitField>) {
+    fn display(&self, str: &str, x: impl ToVariableOrValue<<C as Config>::CircuitField>) {
         let x = self.convert_to_value(x);
-        println!("x: {:?}", x);
+        println!("{}: {:?}", str, x);
     }
 
     fn add(
@@ -372,12 +372,6 @@ impl<C: Config> UnconstrainedAPI<C> for DebugBuilder<C> {
     }
 }
 
-impl<C: Config> DebugAPI<C> for DebugBuilder<C> {
-    fn value_of(&self, x: impl ToVariableOrValue<C::CircuitField>) -> C::CircuitField {
-        self.convert_to_value(x)
-    }
-}
-
 impl<C: Config> RootAPI<C> for DebugBuilder<C> {
     fn memorized_simple_call<F: Fn(&mut Self, &Vec<Variable>) -> Vec<Variable> + 'static>(
         &mut self,
diff --git a/expander_compiler/src/frontend/mod.rs b/expander_compiler/src/frontend/mod.rs
index fe2ffea..99ab895 100644
--- a/expander_compiler/src/frontend/mod.rs
+++ b/expander_compiler/src/frontend/mod.rs
@@ -29,7 +29,7 @@ pub mod internal {
 }
 
 pub mod extra {
-    pub use super::api::{DebugAPI, UnconstrainedAPI};
+    pub use super::api::UnconstrainedAPI;
     pub use super::debug::DebugBuilder;
     pub use crate::utils::serde::Serde;
 
diff --git a/rsa_circuit/src/tests/u2048_mul_no_mod.rs b/rsa_circuit/src/tests/u2048_mul_no_mod.rs
index f75a496..a0ebaf7 100644
--- a/rsa_circuit/src/tests/u2048_mul_no_mod.rs
+++ b/rsa_circuit/src/tests/u2048_mul_no_mod.rs
@@ -28,11 +28,7 @@ impl GenericDefine<BN254Config> for MulNoModCircuit<Variable> {
 
         let res = U2048Variable::mul_without_mod_reduction(&x, &y, &two_to_120, builder);
 
-        // for i in 0..2 * N_LIMBS {
-        //     println!("{i}");
-        //     builder.display(res[i]);
-        //     builder.display(self.result[i]);
-        // }
+        // builder.display("first limb", x.limbs[0]);
 
         for i in 0..2 * N_LIMBS {
             builder.assert_is_equal(res[i], self.result[i]);