diff --git a/src/lang/errors.ts b/src/lang/errors.ts
index df6d6b371..d6085a303 100644
--- a/src/lang/errors.ts
+++ b/src/lang/errors.ts
@@ -159,7 +159,7 @@ export class KCLTypeError extends KCLError {
   }
 }
 
-export class KCLUnimplementedError extends KCLError {
+export class KCLIoError extends KCLError {
   constructor(
     msg: string,
     sourceRange: SourceRange,
@@ -169,7 +169,7 @@ export class KCLUnimplementedError extends KCLError {
     filenames: { [x: number]: ModulePath | undefined }
   ) {
     super(
-      'unimplemented',
+      'io',
       msg,
       sourceRange,
       operations,
@@ -177,7 +177,7 @@ export class KCLUnimplementedError extends KCLError {
       artifactGraph,
       filenames
     )
-    Object.setPrototypeOf(this, KCLUnimplementedError.prototype)
+    Object.setPrototypeOf(this, KCLIoError.prototype)
   }
 }
 
diff --git a/src/wasm-lib/kcl/src/errors.rs b/src/wasm-lib/kcl/src/errors.rs
index 3168f75ff..226125a82 100644
--- a/src/wasm-lib/kcl/src/errors.rs
+++ b/src/wasm-lib/kcl/src/errors.rs
@@ -87,8 +87,8 @@ pub enum KclError {
     ImportCycle(KclErrorDetails),
     #[error("type: {0:?}")]
     Type(KclErrorDetails),
-    #[error("unimplemented: {0:?}")]
-    Unimplemented(KclErrorDetails),
+    #[error("i/o: {0:?}")]
+    Io(KclErrorDetails),
     #[error("unexpected: {0:?}")]
     Unexpected(KclErrorDetails),
     #[error("value already defined: {0:?}")]
@@ -268,7 +268,7 @@ impl miette::Diagnostic for ReportWithOutputs {
             KclError::Semantic(_) => "Semantic",
             KclError::ImportCycle(_) => "ImportCycle",
             KclError::Type(_) => "Type",
-            KclError::Unimplemented(_) => "Unimplemented",
+            KclError::Io(_) => "I/O",
             KclError::Unexpected(_) => "Unexpected",
             KclError::ValueAlreadyDefined(_) => "ValueAlreadyDefined",
             KclError::UndefinedValue(_) => "UndefinedValue",
@@ -318,7 +318,7 @@ impl miette::Diagnostic for Report {
             KclError::Semantic(_) => "Semantic",
             KclError::ImportCycle(_) => "ImportCycle",
             KclError::Type(_) => "Type",
-            KclError::Unimplemented(_) => "Unimplemented",
+            KclError::Io(_) => "I/O",
             KclError::Unexpected(_) => "Unexpected",
             KclError::ValueAlreadyDefined(_) => "ValueAlreadyDefined",
             KclError::UndefinedValue(_) => "UndefinedValue",
@@ -377,7 +377,7 @@ impl KclError {
             KclError::Semantic(_) => "semantic",
             KclError::ImportCycle(_) => "import cycle",
             KclError::Type(_) => "type",
-            KclError::Unimplemented(_) => "unimplemented",
+            KclError::Io(_) => "i/o",
             KclError::Unexpected(_) => "unexpected",
             KclError::ValueAlreadyDefined(_) => "value already defined",
             KclError::UndefinedValue(_) => "undefined value",
@@ -394,7 +394,7 @@ impl KclError {
             KclError::Semantic(e) => e.source_ranges.clone(),
             KclError::ImportCycle(e) => e.source_ranges.clone(),
             KclError::Type(e) => e.source_ranges.clone(),
-            KclError::Unimplemented(e) => e.source_ranges.clone(),
+            KclError::Io(e) => e.source_ranges.clone(),
             KclError::Unexpected(e) => e.source_ranges.clone(),
             KclError::ValueAlreadyDefined(e) => e.source_ranges.clone(),
             KclError::UndefinedValue(e) => e.source_ranges.clone(),
@@ -412,7 +412,7 @@ impl KclError {
             KclError::Semantic(e) => &e.message,
             KclError::ImportCycle(e) => &e.message,
             KclError::Type(e) => &e.message,
-            KclError::Unimplemented(e) => &e.message,
+            KclError::Io(e) => &e.message,
             KclError::Unexpected(e) => &e.message,
             KclError::ValueAlreadyDefined(e) => &e.message,
             KclError::UndefinedValue(e) => &e.message,
@@ -430,7 +430,7 @@ impl KclError {
             KclError::Semantic(e) => e.source_ranges = source_ranges,
             KclError::ImportCycle(e) => e.source_ranges = source_ranges,
             KclError::Type(e) => e.source_ranges = source_ranges,
-            KclError::Unimplemented(e) => e.source_ranges = source_ranges,
+            KclError::Io(e) => e.source_ranges = source_ranges,
             KclError::Unexpected(e) => e.source_ranges = source_ranges,
             KclError::ValueAlreadyDefined(e) => e.source_ranges = source_ranges,
             KclError::UndefinedValue(e) => e.source_ranges = source_ranges,
@@ -450,7 +450,7 @@ impl KclError {
             KclError::Semantic(e) => e.source_ranges.extend(source_ranges),
             KclError::ImportCycle(e) => e.source_ranges.extend(source_ranges),
             KclError::Type(e) => e.source_ranges.extend(source_ranges),
-            KclError::Unimplemented(e) => e.source_ranges.extend(source_ranges),
+            KclError::Io(e) => e.source_ranges.extend(source_ranges),
             KclError::Unexpected(e) => e.source_ranges.extend(source_ranges),
             KclError::ValueAlreadyDefined(e) => e.source_ranges.extend(source_ranges),
             KclError::UndefinedValue(e) => e.source_ranges.extend(source_ranges),
diff --git a/src/wasm-lib/kcl/src/fs/local.rs b/src/wasm-lib/kcl/src/fs/local.rs
index 562cecac0..2d0f665fd 100644
--- a/src/wasm-lib/kcl/src/fs/local.rs
+++ b/src/wasm-lib/kcl/src/fs/local.rs
@@ -31,7 +31,7 @@ impl FileSystem for FileManager {
         source_range: SourceRange,
     ) -> Result<Vec<u8>, KclError> {
         tokio::fs::read(&path).await.map_err(|e| {
-            KclError::Engine(KclErrorDetails {
+            KclError::Io(KclErrorDetails {
                 message: format!("Failed to read file `{}`: {}", path.as_ref().display(), e),
                 source_ranges: vec![source_range],
             })
@@ -44,7 +44,7 @@ impl FileSystem for FileManager {
         source_range: SourceRange,
     ) -> Result<String, KclError> {
         tokio::fs::read_to_string(&path).await.map_err(|e| {
-            KclError::Engine(KclErrorDetails {
+            KclError::Io(KclErrorDetails {
                 message: format!("Failed to read file `{}`: {}", path.as_ref().display(), e),
                 source_ranges: vec![source_range],
             })
@@ -60,7 +60,7 @@ impl FileSystem for FileManager {
             if e.kind() == std::io::ErrorKind::NotFound {
                 Ok(false)
             } else {
-                Err(KclError::Engine(KclErrorDetails {
+                Err(KclError::Io(KclErrorDetails {
                     message: format!("Failed to check if file `{}` exists: {}", path.as_ref().display(), e),
                     source_ranges: vec![source_range],
                 }))
@@ -82,7 +82,7 @@ impl FileSystem for FileManager {
             }
 
             let mut read_dir = tokio::fs::read_dir(&path).await.map_err(|e| {
-                KclError::Engine(KclErrorDetails {
+                KclError::Io(KclErrorDetails {
                     message: format!("Failed to read directory `{}`: {}", path.display(), e),
                     source_ranges: vec![source_range],
                 })
diff --git a/src/wasm-lib/kcl/tests/import_file_not_exist_error/execution_error.snap b/src/wasm-lib/kcl/tests/import_file_not_exist_error/execution_error.snap
index 5af471db6..44ffd0933 100644
--- a/src/wasm-lib/kcl/tests/import_file_not_exist_error/execution_error.snap
+++ b/src/wasm-lib/kcl/tests/import_file_not_exist_error/execution_error.snap
@@ -2,9 +2,9 @@
 source: kcl/src/simulation_tests.rs
 description: Error from executing import_file_not_exist_error.kcl
 ---
-KCL Engine error
+KCL I/O error
 
-  × engine: Failed to read file `tests/import_file_not_exist_error/not-
+  × i/o: Failed to read file `tests/import_file_not_exist_error/not-
   │ exist.kcl`: No such file or directory (os error 2)
    ╭────
  1 │ import hotdog from "not-exist.kcl"