diff --git a/Cargo.lock b/Cargo.lock
index c8da6a5..1bf5e4d 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -5387,12 +5387,15 @@ dependencies = [
  "nu-ansi-term",
  "once_cell",
  "regex",
+ "serde",
+ "serde_json",
  "sharded-slab",
  "smallvec",
  "thread_local",
  "tracing",
  "tracing-core",
  "tracing-log 0.2.0",
+ "tracing-serde",
 ]
 
 [[package]]
diff --git a/Cargo.toml b/Cargo.toml
index 8ead94f..e24cfb3 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -21,7 +21,7 @@ sha3 = "0.10.8"
 tokio = { version = "1.35.1", features = ["macros", "rt-multi-thread", "parking_lot"] }
 tower-http = { version = "0.5.0", features = ["trace", "compression-br"] }
 tracing = "0.1.40"
-tracing-subscriber = { version = "0.3.18", features = ["env-filter"] }
+tracing-subscriber = { version = "0.3.18", features = ["env-filter", "json"] }
 sp-io = "32.0.0"
 sp-core = "30.0.0"
 chrono = "0.4.34"
diff --git a/src/main.rs b/src/main.rs
index be08867..e8e2c94 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -53,6 +53,7 @@ struct IndexStruct {
 #[serde(rename_all = "camelCase")]
 struct KateQueryDataProofV2Response {
     data_proof: DataProof,
+    #[cfg_attr(feature = "serde", serde(skip_serializing_if = "Option::is_none"))]
     message: Option<Message>,
 }
 
@@ -204,7 +205,7 @@ async fn get_eth_proof(
         Ok(resp) => match resp {
             Ok(data) => data,
             Err(err) => {
-                tracing::error!("❌ {:?}", err);
+                tracing::error!("❌ Cannot query data proof {:?}", err);
                 return (
                     StatusCode::BAD_REQUEST,
                     [("Cache-Control", "max-age=300, must-revalidate")],
@@ -279,7 +280,7 @@ async fn get_eth_proof(
             blob_root: data_proof_res.data_proof.blob_root,
             bridge_root: data_proof_res.data_proof.bridge_root,
             data_root_commitment: succinct_data.data_commitment,
-            block_hash: block_hash,
+            block_hash,
             message: data_proof_res.message
         })),
     )
@@ -510,7 +511,7 @@ async fn get_avl_head(State(state): State<Arc<AppState>>) -> impl IntoResponse {
 async fn main() {
     dotenvy::dotenv().ok();
     tracing_subscriber::registry()
-        .with(tracing_subscriber::fmt::layer())
+        .with(tracing_subscriber::fmt::layer().json())
         .with(
             tracing_subscriber::EnvFilter::try_from_default_env().unwrap_or_else(|_| {
                 "bridge_api=debug,tower_http=debug,axum::rejection=trace".into()