diff --git a/crates/e2e-move-tests/Cargo.toml b/crates/e2e-move-tests/Cargo.toml
index d6b5e665..f66ce477 100644
--- a/crates/e2e-move-tests/Cargo.toml
+++ b/crates/e2e-move-tests/Cargo.toml
@@ -22,6 +22,7 @@ sha3 = { workspace = true }
 bytes = { workspace = true }
 bigdecimal = { workspace = true }
 bech32 = { workspace = true }
+base64 = { workspace = true }
 
 initia-move-types = { workspace = true }
 initia-move-vm = { workspace = true }
diff --git a/crates/e2e-move-tests/src/tests/cosmos.rs b/crates/e2e-move-tests/src/tests/cosmos.rs
index 9877ddc1..d3fe38f1 100644
--- a/crates/e2e-move-tests/src/tests/cosmos.rs
+++ b/crates/e2e-move-tests/src/tests/cosmos.rs
@@ -8,6 +8,7 @@ use move_core_types::account_address::AccountAddress;
 use move_core_types::language_storage::TypeTag;
 use move_core_types::vm_status::VMStatus;
 
+use base64::{self, Engine};
 use bech32::{Bech32, Hrp};
 use sha3::{Digest, Sha3_256};
 
@@ -397,7 +398,7 @@ fn test_cosmos_pay_fee() {
     let timeout_fee_denom = str::from_utf8(FEE_B_SYMBOL).unwrap();
     let sender_cosmos_addr =
         bech32::encode::<Bech32>(Hrp::parse_unchecked("init"), &sender.into_bytes()).unwrap();
-    let expected_data = format!("{{\"@type\":\"/ibc.applications.fee.v1.MsgPayPacketFee\",\"fee\":{{\"ack_fee\":[{{\"amount\":\"{ack_fee_amount}\",\"denom\":\"{ack_fee_denom}\"}}],\"recv_fee\":[{{\"amount\":\"{recv_fee_amount}\",\"denom\":\"{recv_fee_denom}\"}}],\"timeout_fee\":[{{\"amount\":\"{timeout_fee_amount}\",\"denom\":\"{timeout_fee_denom}\"}}]}},\"relayers\":[],\"signer\":\"{sender_cosmos_addr}\",\"source_channel\":\"{source_channel}\",\"source_port\":\"{source_port}\"}}");
+    let expected_data = format!("{{\"@type\":\"/ibc.applications.fee.v1.MsgPayPacketFee\",\"fee\":{{\"ack_fee\":[{{\"amount\":\"{ack_fee_amount}\",\"denom\":\"{ack_fee_denom}\"}}],\"recv_fee\":[{{\"amount\":\"{recv_fee_amount}\",\"denom\":\"{recv_fee_denom}\"}}],\"timeout_fee\":[{{\"amount\":\"{timeout_fee_amount}\",\"denom\":\"{timeout_fee_denom}\"}}]}},\"relayers\":[],\"signer\":\"{sender_cosmos_addr}\",\"source_channel_id\":\"{source_channel}\",\"source_port_id\":\"{source_port}\"}}");
 
     let test_pay_fee = (
         sender,
@@ -442,12 +443,13 @@ fn test_cosmos_move_execute() {
     let arg1 = vec![1, 2, 3];
     let arg2 = vec![4, 5, 6];
 
-    let arg1_hex = hex::encode(arg1.clone());
-    let arg2_hex = hex::encode(arg2.clone());
+    let base64 = base64::engine::general_purpose::STANDARD;
+    let arg1_base64 = base64.encode(arg1.clone());
+    let arg2_base64 = base64.encode(arg2.clone());
     let module_addr_hex = module_address.to_hex_literal();
     let sender_cosmos_addr =
         bech32::encode::<Bech32>(Hrp::parse_unchecked("init"), &sender.into_bytes()).unwrap();
-    let expected_data = format!("{{\"@type\":\"/initia.move.v1.MsgExecute\",\"args\":[\"{arg1_hex}\",\"{arg2_hex}\"],\"function_name\":\"{function_name}\",\"module_address\":\"{module_addr_hex}\",\"module_name\":\"{module_name}\",\"sender\":\"{sender_cosmos_addr}\",\"type_args\":[\"{type_arg1}\",\"{type_arg2}\"]}}");
+    let expected_data = format!("{{\"@type\":\"/initia.move.v1.MsgExecute\",\"args\":[\"{arg1_base64}\",\"{arg2_base64}\"],\"function_name\":\"{function_name}\",\"module_address\":\"{module_addr_hex}\",\"module_name\":\"{module_name}\",\"sender\":\"{sender_cosmos_addr}\",\"type_args\":[\"{type_arg1}\",\"{type_arg2}\"]}}");
 
     let test_move_execute = (
         sender,
@@ -532,12 +534,13 @@ fn test_cosmos_move_script() {
     let arg1 = vec![1, 2, 3];
     let arg2 = vec![4, 5, 6];
 
-    let code_bytes_hex = hex::encode(code_bytes.clone());
-    let arg1_hex = hex::encode(arg1.clone());
-    let arg2_hex = hex::encode(arg2.clone());
+    let base64 = base64::engine::general_purpose::STANDARD;
+    let code_bytes_base64 = base64.encode(code_bytes.clone());
+    let arg1_base64 = base64.encode(arg1.clone());
+    let arg2_base64 = base64.encode(arg2.clone());
     let sender_cosmos_addr =
         bech32::encode::<Bech32>(Hrp::parse_unchecked("init"), &sender.into_bytes()).unwrap();
-    let expected_data = format!("{{\"@type\":\"/initia.move.v1.MsgScript\",\"args\":[\"{arg1_hex}\",\"{arg2_hex}\"],\"code_bytes\":\"{code_bytes_hex}\",\"sender\":\"{sender_cosmos_addr}\",\"type_args\":[\"{type_arg1}\",\"{type_arg2}\"]}}");
+    let expected_data = format!("{{\"@type\":\"/initia.move.v1.MsgScript\",\"args\":[\"{arg1_base64}\",\"{arg2_base64}\"],\"code_bytes\":\"{code_bytes_base64}\",\"sender\":\"{sender_cosmos_addr}\",\"type_args\":[\"{type_arg1}\",\"{type_arg2}\"]}}");
 
     let test_move_script = (
         sender,
@@ -575,10 +578,11 @@ fn test_cosmos_move_script_with_json() {
     let arg1 = b"\"hello\"".to_vec();
     let arg2 = b"\"world\"".to_vec();
 
-    let code_bytes_hex = hex::encode(code_bytes.clone());
+    let base64 = base64::engine::general_purpose::STANDARD;
+    let code_bytes_base64 = base64.encode(code_bytes.clone());
     let sender_cosmos_addr =
         bech32::encode::<Bech32>(Hrp::parse_unchecked("init"), &sender.into_bytes()).unwrap();
-    let expected_data = format!("{{\"@type\":\"/initia.move.v1.MsgScriptJSON\",\"args\":[\"\\\"hello\\\"\",\"\\\"world\\\"\"],\"code_bytes\":\"{code_bytes_hex}\",\"sender\":\"{sender_cosmos_addr}\",\"type_args\":[\"{type_arg1}\",\"{type_arg2}\"]}}");
+    let expected_data = format!("{{\"@type\":\"/initia.move.v1.MsgScriptJSON\",\"args\":[\"\\\"hello\\\"\",\"\\\"world\\\"\"],\"code_bytes\":\"{code_bytes_base64}\",\"sender\":\"{sender_cosmos_addr}\",\"type_args\":[\"{type_arg1}\",\"{type_arg2}\"]}}");
 
     let test_move_script = (
         sender,
diff --git a/precompile/binaries/minlib/cosmos.mv b/precompile/binaries/minlib/cosmos.mv
index cac09be4..1225e496 100644
Binary files a/precompile/binaries/minlib/cosmos.mv and b/precompile/binaries/minlib/cosmos.mv differ
diff --git a/precompile/binaries/stdlib/cosmos.mv b/precompile/binaries/stdlib/cosmos.mv
index cac09be4..1225e496 100644
Binary files a/precompile/binaries/stdlib/cosmos.mv and b/precompile/binaries/stdlib/cosmos.mv differ
diff --git a/precompile/modules/initia_stdlib/sources/cosmos.move b/precompile/modules/initia_stdlib/sources/cosmos.move
index 46faa211..237f975c 100644
--- a/precompile/modules/initia_stdlib/sources/cosmos.move
+++ b/precompile/modules/initia_stdlib/sources/cosmos.move
@@ -11,6 +11,7 @@ module initia_std::cosmos {
     use std::error;
     use std::coin::metadata_to_denom;
     use std::collection::collection_to_class_id;
+    use std::base64;
 
     use initia_std::json;
 
@@ -78,7 +79,7 @@ module initia_std::cosmos {
         module_name: String,
         function_name: String,
         type_args: vector<String>,
-        args: vector<vector<u8>>
+        args: vector<String> // base64 encoded
     }
 
     public entry fun move_execute(
@@ -89,6 +90,7 @@ module initia_std::cosmos {
         type_args: vector<String>,
         args: vector<vector<u8>>
     ) {
+        let args = vector::map(args, |arg| base64::to_string(arg));
         stargate(
             sender,
             json::marshal(
@@ -142,9 +144,9 @@ module initia_std::cosmos {
     struct ScriptRequest has copy, drop {
         _type_: String,
         sender: String,
-        code_bytes: vector<u8>,
+        code_bytes: String, // base64 encoded
         type_args: vector<String>,
-        args: vector<vector<u8>>
+        args: vector<String> // base64 encoded
     }
 
     public entry fun move_script(
@@ -153,6 +155,8 @@ module initia_std::cosmos {
         type_args: vector<String>,
         args: vector<vector<u8>>
     ) {
+        let args = vector::map(args, |arg| base64::to_string(arg));
+        let code_bytes = base64::to_string(code_bytes);
         stargate(
             sender,
             json::marshal(
@@ -170,7 +174,7 @@ module initia_std::cosmos {
     struct ScriptJSONRequest has copy, drop {
         _type_: String,
         sender: String,
-        code_bytes: vector<u8>,
+        code_bytes: String,
         type_args: vector<String>,
         args: vector<String>
     }
@@ -181,6 +185,7 @@ module initia_std::cosmos {
         type_args: vector<String>,
         args: vector<String>
     ) {
+        let code_bytes = base64::to_string(code_bytes);
         stargate(
             sender,
             json::marshal(
@@ -356,8 +361,8 @@ module initia_std::cosmos {
     struct PayFeeRequest has copy, drop {
         _type_: String,
         _signer_: String,
-        source_port: String,
-        source_channel: String,
+        source_port_id: String,
+        source_channel_id: String,
         fee: Fee,
         relayers: vector<String>
     }
@@ -381,8 +386,8 @@ module initia_std::cosmos {
                 &PayFeeRequest {
                     _type_: string::utf8(b"/ibc.applications.fee.v1.MsgPayPacketFee"),
                     _signer_: address::to_sdk(signer::address_of(sender)),
-                    source_port,
-                    source_channel,
+                    source_port_id: source_port,
+                    source_channel_id: source_channel,
                     fee: Fee {
                         recv_fee: vector[
                             CosmosCoin {
diff --git a/precompile/modules/minitia_stdlib/sources/cosmos.move b/precompile/modules/minitia_stdlib/sources/cosmos.move
index 045b61ec..ce745752 100644
--- a/precompile/modules/minitia_stdlib/sources/cosmos.move
+++ b/precompile/modules/minitia_stdlib/sources/cosmos.move
@@ -11,6 +11,7 @@ module minitia_std::cosmos {
     use std::error;
     use std::coin::metadata_to_denom;
     use std::collection::collection_to_class_id;
+    use std::base64;
 
     use minitia_std::json;
 
@@ -78,7 +79,7 @@ module minitia_std::cosmos {
         module_name: String,
         function_name: String,
         type_args: vector<String>,
-        args: vector<vector<u8>>
+        args: vector<String> // base64 encoded
     }
 
     public entry fun move_execute(
@@ -89,6 +90,7 @@ module minitia_std::cosmos {
         type_args: vector<String>,
         args: vector<vector<u8>>
     ) {
+        let args = vector::map(args, |arg| base64::to_string(arg));
         stargate(
             sender,
             json::marshal(
@@ -142,9 +144,9 @@ module minitia_std::cosmos {
     struct ScriptRequest has copy, drop {
         _type_: String,
         sender: String,
-        code_bytes: vector<u8>,
+        code_bytes: String, // base64 encoded
         type_args: vector<String>,
-        args: vector<vector<u8>>
+        args: vector<String> // base64 encoded
     }
 
     public entry fun move_script(
@@ -153,6 +155,8 @@ module minitia_std::cosmos {
         type_args: vector<String>,
         args: vector<vector<u8>>
     ) {
+        let args = vector::map(args, |arg| base64::to_string(arg));
+        let code_bytes = base64::to_string(code_bytes);
         stargate(
             sender,
             json::marshal(
@@ -170,7 +174,7 @@ module minitia_std::cosmos {
     struct ScriptJSONRequest has copy, drop {
         _type_: String,
         sender: String,
-        code_bytes: vector<u8>,
+        code_bytes: String,
         type_args: vector<String>,
         args: vector<String>
     }
@@ -181,6 +185,7 @@ module minitia_std::cosmos {
         type_args: vector<String>,
         args: vector<String>
     ) {
+        let code_bytes = base64::to_string(code_bytes);
         stargate(
             sender,
             json::marshal(
@@ -356,8 +361,8 @@ module minitia_std::cosmos {
     struct PayFeeRequest has copy, drop {
         _type_: String,
         _signer_: String,
-        source_port: String,
-        source_channel: String,
+        source_port_id: String,
+        source_channel_id: String,
         fee: Fee,
         relayers: vector<String>
     }
@@ -381,8 +386,8 @@ module minitia_std::cosmos {
                 &PayFeeRequest {
                     _type_: string::utf8(b"/ibc.applications.fee.v1.MsgPayPacketFee"),
                     _signer_: address::to_sdk(signer::address_of(sender)),
-                    source_port,
-                    source_channel,
+                    source_port_id: source_port,
+                    source_channel_id: source_channel,
                     fee: Fee {
                         recv_fee: vector[
                             CosmosCoin {