diff --git a/kclvm/error/src/lib.rs b/kclvm/error/src/lib.rs
index 5b419a3f2..facd304db 100644
--- a/kclvm/error/src/lib.rs
+++ b/kclvm/error/src/lib.rs
@@ -554,11 +554,26 @@ impl SessionDiagnostic for Diagnostic {
                             diag.append_component(Box::new(format!("{dl}\n")));
                         }
                         None => {
-                            diag.append_component(Box::new(format!("{}\n", msg.message)));
+                            let info = msg.range.0.info();
+                            if !info.is_empty() {
+                                diag.append_component(Box::new(format!(
+                                    "{}: {}\n",
+                                    info, msg.message
+                                )));
+                            } else {
+                                diag.append_component(Box::new(format!("{}\n", msg.message)));
+                            }
                         }
                     };
                 }
-                Err(_) => diag.append_component(Box::new(format!("{}\n", msg.message))),
+                Err(_) => {
+                    let info = msg.range.0.info();
+                    if !info.is_empty() {
+                        diag.append_component(Box::new(format!("{}: {}\n", info, msg.message)));
+                    } else {
+                        diag.append_component(Box::new(format!("{}\n", msg.message)));
+                    }
+                }
             };
             if let Some(note) = &msg.note {
                 diag.append_component(Box::new(Label::Note));
diff --git a/kclvm/runner/src/runner.rs b/kclvm/runner/src/runner.rs
index 85f9be358..806ec56d0 100644
--- a/kclvm/runner/src/runner.rs
+++ b/kclvm/runner/src/runner.rs
@@ -460,7 +460,7 @@ impl LibRunner {
 }
 
 thread_local! {
-    static KCL_RUNTIME_PANIC_RECORD: RefCell<RuntimePanicRecord>  = RefCell::new(RuntimePanicRecord::default())
+    pub static KCL_RUNTIME_PANIC_RECORD: RefCell<RuntimePanicRecord>  = RefCell::new(RuntimePanicRecord::default())
 }
 
 pub struct FastRunner {
@@ -491,7 +491,7 @@ impl FastRunner {
                 } else if let Some(s) = info.payload().downcast_ref::<String>() {
                     (*s).clone()
                 } else {
-                    "".to_string()
+                    "unknown runtime error".to_string()
                 };
                 if let Some(location) = info.location() {
                     record.rust_file = location.file().to_string();
diff --git a/kclvm/src/lib.rs b/kclvm/src/lib.rs
index 70d23b148..15bd00125 100644
--- a/kclvm/src/lib.rs
+++ b/kclvm/src/lib.rs
@@ -161,6 +161,24 @@ pub unsafe extern "C" fn kcl_fmt(src_ptr: *const c_char) -> *const c_char {
     }
 }
 
+/// Exposes a normal kcl runtime error function to the WASM host.
+#[no_mangle]
+pub unsafe extern "C" fn kcl_runtime_err(buffer: *mut u8, length: usize) -> isize {
+    KCL_RUNTIME_PANIC_RECORD.with(|e| {
+        let message = &e.borrow().message;
+        if !message.is_empty() {
+            let bytes = message.as_bytes();
+            let copy_len = std::cmp::min(bytes.len(), length);
+            unsafe {
+                std::ptr::copy_nonoverlapping(bytes.as_ptr(), buffer, copy_len);
+            }
+            copy_len as isize
+        } else {
+            0
+        }
+    })
+}
+
 fn intern_fmt(src: &str) -> Result<String, String> {
     let api = API::default();
     let args = &FormatCodeArgs {
@@ -182,12 +200,12 @@ pub unsafe extern "C" fn kcl_malloc(size: usize) -> *mut u8 {
     if layout.size() > 0 {
         let ptr = alloc(layout);
         if !ptr.is_null() {
-            return ptr;
+            ptr
         } else {
             std::alloc::handle_alloc_error(layout);
         }
     } else {
-        return align as *mut u8;
+        align as *mut u8
     }
 }