From 70e866f83a6b1bc7727544b8b114606c81ef9b6c Mon Sep 17 00:00:00 2001
From: cordeirops <pedro.sbarainicordeiro@gmail.com>
Date: Wed, 19 Nov 2025 19:37:57 -0300
Subject: [PATCH 01/12] Add TaskMissingError exception and handle missing
 pipeline steps

- Introduced TaskMissingError to signal when a pipeline lacks steps.
- Updated the compiler to raise TaskMissingError if no steps are present.
- Mapped TaskMissingError to RPCTaskIsMissing for RPC error handling.
- Enhanced error handling in the notebook compilation process to provide user guidance for missing steps.
- Added utility functions in the UI to display informative dialogs for missing pipeline steps.

Signed-off-by: cordeirops <pedro.sbarainicordeiro@gmail.com>
---
 backend/kale/compiler.py               |  7 +++
 backend/kale/errors.py                 | 12 +++++
 backend/kale/rpc/errors.py             |  9 ++++
 backend/kale/rpc/nb.py                 | 64 +++++++++++++++++------
 labextension/src/lib/RPCUtils.tsx      | 70 ++++++++++++++++++++++++--
 labextension/src/widgets/LeftPanel.tsx | 53 ++++++++++++++++++-
 6 files changed, 195 insertions(+), 20 deletions(-)
 create mode 100644 backend/kale/errors.py

diff --git a/backend/kale/compiler.py b/backend/kale/compiler.py
index 663f68bd2..792e0dfb2 100644
--- a/backend/kale/compiler.py
+++ b/backend/kale/compiler.py
@@ -12,6 +12,7 @@
 from kale import __version__ as KALE_VERSION
 from kale.pipeline import Pipeline, Step, PipelineParam
 from kale.common import kfputils, utils, graphutils
+from kale.errors import TaskMissingError
 
 log = logging.getLogger(__name__)
 
@@ -89,6 +90,12 @@ def generate_dsl(self):
 
         Returns (str): A Python executable script
         """
+        # Fail early if there are no steps in the pipeline. Raise a domain-
+        # specific exception so higher layers (RPC) can map it to an RPC
+        # error without coupling core to the RPC layer.
+        if not hasattr(self.pipeline, 'steps') or not self.pipeline.steps:
+            raise TaskMissingError('Task is missing from pipeline.')
+
         # List of lightweight components generated code
         lightweight_components = [
             self.generate_lightweight_component(step)
diff --git a/backend/kale/errors.py b/backend/kale/errors.py
new file mode 100644
index 000000000..9d689b250
--- /dev/null
+++ b/backend/kale/errors.py
@@ -0,0 +1,12 @@
+"""Core domain exceptions for Kale (non-RPC).
+Keep domain-specific exceptions here so core modules (compiler, processor)
+can raise them without depending on RPC layer.
+"""
+
+
+class TaskMissingError(Exception):
+    """Raised when a Pipeline has no steps/tasks.
+    This is a domain-level exception and will be mapped to an RPC error
+    (RPCTaskIsMissing) by the RPC handler.
+    """
+    pass
diff --git a/backend/kale/rpc/errors.py b/backend/kale/rpc/errors.py
index b56e32471..204c203c5 100644
--- a/backend/kale/rpc/errors.py
+++ b/backend/kale/rpc/errors.py
@@ -16,6 +16,7 @@ class Code(enum.Enum):
     INTERNAL_ERROR = 4
     SERVICE_UNAVAILABLE = 5
     UNHANDLED_ERROR = 6
+    TASK_IS_MISSING = 7
 
 
 class _RPCError(Exception):
@@ -76,6 +77,14 @@ class RPCServiceUnavailableError(_RPCError):
     message = "Service is Unavailable"
 
 
+class RPCTaskIsMissing(_RPCError):
+    """Task is missing from pipeline, you must add a pipeline step."""
+
+    name = "taskIsMissing"
+    code = Code.TASK_IS_MISSING
+    message = "Task is missing from pipeline, you must add a pipeline step."
+
+
 class RPCUnhandledError(_RPCError):
     """Unhandled RPC Error."""
 
diff --git a/backend/kale/rpc/nb.py b/backend/kale/rpc/nb.py
index cfc2bbf8f..2e201a6be 100644
--- a/backend/kale/rpc/nb.py
+++ b/backend/kale/rpc/nb.py
@@ -10,7 +10,8 @@
 from kale import marshal
 from kale.rpc.log import create_adapter
 from kale import Compiler, NotebookProcessor
-from kale.rpc.errors import RPCInternalError
+from kale.rpc.errors import RPCInternalError, RPCTaskIsMissing
+from kale.errors import TaskMissingError
 from kale.common import podutils, kfputils, kfutils, astutils
 
 KALE_MARSHAL_DIR_POSTFIX = ".kale.marshal.dir"
@@ -80,20 +81,53 @@ def get_base_image(request):
 def compile_notebook(request, source_notebook_path,
                      notebook_metadata_overrides=None, debug=False):
     """Compile the notebook to KFP DSL."""
-    processor = NotebookProcessor(source_notebook_path,
-                                  notebook_metadata_overrides)
-    pipeline = processor.run()
-    imports_and_functions = processor.get_imports_and_functions()
-    script_path = Compiler(pipeline, imports_and_functions).compile()
-    # FIXME: Why were we tapping into the Kale logger?
-    # instance = Kale(source_notebook_path, notebook_metadata_overrides, debug)
-    # instance.logger = request.log if hasattr(request, "log") else logger
-
-    package_path = kfputils.compile_pipeline(script_path,
-                                             pipeline.config.pipeline_name)
-
-    return {"pipeline_package_path": os.path.relpath(package_path),
-            "pipeline_metadata": pipeline.config.to_dict()}
+    try:
+        processor = NotebookProcessor(source_notebook_path,
+                                      notebook_metadata_overrides)
+        pipeline = processor.run()
+        imports_and_functions = processor.get_imports_and_functions()
+        script_path = Compiler(pipeline, imports_and_functions).compile()
+
+        """FIXME: Why were we tapping into the Kale logger?
+        instance = Kale(source_notebook_path,
+        notebook_metadata_overrides, debug)
+        instance.logger = request.log if
+        hasattr(request, "log") else logger"""
+
+        package_path = kfputils.compile_pipeline(script_path,
+                                                 pipeline.config.pipeline_name)
+
+        return {"pipeline_package_path": os.path.relpath(package_path),
+                "pipeline_metadata": pipeline.config.to_dict()}
+    except TaskMissingError as e:
+        # Domain-specific exception raised by core components when no
+        # pipeline steps are present. Map it to a specific RPC error so the
+        # frontend receives a concrete error code and message. Provide a
+        # slightly more actionable `details` field so the UI can display
+        # guidance to the user about how to fix the issue (e.g., tag a
+        # cell as a step or set `steps_defaults` in metadata).
+        msg = str(e)
+        request.log.exception("TaskMissingError during notebook "
+                              "compilation: %s", msg)
+        raise RPCTaskIsMissing(details=msg, trans_id=request.trans_id)
+    except ValueError as e:
+        # kfp.compiler or graph_component may
+        # raise ValueError for other
+        # reasons; map them to an internal
+        # RPC error (unless they match the
+        # specific message — kept for backward compatibility).
+        msg = str(e)
+        request.log.exception("ValueError during notebook"
+                              " compilation: %s", msg)
+        if 'Task is missing from pipeline' in msg:
+            raise RPCTaskIsMissing(details=msg, trans_id=request.trans_id)
+        raise RPCInternalError(details=msg, trans_id=request.trans_id)
+    except Exception as e:
+        # Let the run dispatcher handle generic exceptions as unhandled,
+        # but log for debug purposes.
+        request.log.exception("Unexpected error during "
+                              "notebook compilation: %s", e)
+        raise
 
 
 def validate_notebook(request, source_notebook_path,
diff --git a/labextension/src/lib/RPCUtils.tsx b/labextension/src/lib/RPCUtils.tsx
index 4a180304a..2cd5eaf61 100644
--- a/labextension/src/lib/RPCUtils.tsx
+++ b/labextension/src/lib/RPCUtils.tsx
@@ -5,8 +5,10 @@ import * as React from 'react';
 import { NotebookPanel } from '@jupyterlab/notebook';
 import { Kernel } from '@jupyterlab/services';
 import NotebookUtils from './NotebookUtils';
+// @ts-expect-error This module is not typed
+import SanitizedHTML from 'react-sanitized-html';
 import { isError, IError, IOutput } from '@jupyterlab/nbformat';
-import { Notification } from '@jupyterlab/apputils';
+import { Notification, Dialog, showDialog } from '@jupyterlab/apputils';
 
 export const globalUnhandledRejection = async (event: any) => {
   console.error(event.reason);
@@ -26,7 +28,7 @@ export const globalUnhandledRejection = async (event: any) => {
       const extensionName = getExtensionName(stackLines)
       Notification.error(`An unhandled error has been thrown.`, {
         actions: [
-          { label: 'Details', callback: () => NotebookUtils.showMessage(alert_string, 
+          { label: 'Details', callback: () => NotebookUtils.showMessage(alert_string,
             ["An unhandled error was thrown from:",
               extensionName,
               "Please see console for more details."
@@ -72,6 +74,7 @@ export enum RPC_CALL_STATUS {
   InternalError = 4,
   ServiceUnavailable = 5,
   UnhandledError = 6,
+  TaskIsMissing = 7,
 }
 
 const getRpcCodeName = (code: number) => {
@@ -88,6 +91,8 @@ const getRpcCodeName = (code: number) => {
       return 'InternalError';
     case RPC_CALL_STATUS.ServiceUnavailable:
       return 'ServiceUnavailable';
+    case RPC_CALL_STATUS.TaskIsMissing:
+      return 'TaskIsMissing';
     default:
       return 'UnhandledError';
   }
@@ -238,6 +243,10 @@ export const showRpcError = async (
   error: IRPCError,
   refresh: boolean = false,
 ): Promise<void> => {
+  if (error && error.code === RPC_CALL_STATUS.TaskIsMissing) {
+    return await handleMissingPipelineStep(error);
+  }
+
   await showError(
     'An RPC Error has occurred',
     'RPC',
@@ -314,7 +323,7 @@ export abstract class BaseError extends Error {
     super(message);
     this.name = this.constructor.name;
     this.stack = new Error(message).stack;
-    
+
     Object.setPrototypeOf(this, BaseError.prototype);
   }
 
@@ -367,3 +376,58 @@ export class RPCError extends BaseError {
     await showRpcError(this.error, refresh);
   }
 }
+
+
+/**
+ * handleMissingPipelineStep - Async handler for missing pipeline step RPC errors.
+ *
+ * Displays a modal dialog that informs the user that a pipeline step is missing,
+ * shows the RPC-provided message and details, and suggests remediation steps:
+ * tagging a code cell as a pipeline step or setting the notebook metadata
+ * `steps_defaults` to include the step name(s). The dialog body is rendered as
+ * sanitized HTML with a restricted set of allowed tags and attributes to avoid
+ * injection issues. The dialog offers two buttons: "Open docs" and "Close".
+ * Selecting "Open docs" opens the Kale README/docs page in a new browser tab.
+ *
+ * @param error - The IRPCError instance containing `err_message` and `err_details`
+ *                to present in the dialog body.
+ * @returns A Promise that resolves once the user dismisses the dialog. If the
+ *          user clicked "Open docs", the documentation page will be opened
+ *          in a new tab as a fallback/help resource.
+ */
+async function handleMissingPipelineStep(error: IRPCError) {
+  const title = 'Pipeline step missing';
+  const bodyLines = [
+    `Message: ${error.err_message}`,
+    '',
+    `Details: ${error.err_details}`,
+    '',
+    'You can fix this by tagging a code cell as a pipeline step (e.g. using the Left Panel), or by setting the notebook metadata `steps_defaults` to a list with the step name(s).',
+  ];
+  const body = (
+    <div className="dialog-body">
+      {bodyLines.map((s: string, i: number) => (
+        <React.Fragment key={`msg-${i}`}>
+          <SanitizedHTML
+            allowedAttributes={{ a: ['href'] }}
+            allowedTags={['b', 'i', 'em', 'strong', 'a', 'pre']}
+            html={s} />
+          <br />
+        </React.Fragment>
+      ))}
+    </div>
+  );
+  const buttons: ReadonlyArray<Dialog.IButton> = [
+    Dialog.okButton({ label: 'Open docs' }),
+    Dialog.cancelButton({ label: 'Close' }),
+  ];
+  const result = await showDialog({ title, body, buttons });
+  const clicked = result.button ? (result.button.label as string) : '';
+  if (clicked === 'Open docs') {
+    // Open the documentation in a new tab (repo README as fallback)
+    const docsUrl = 'https://github.com/kubeflow-kale/kale#readme';
+    window.open(docsUrl, '_blank');
+  }
+  return;
+}
+
diff --git a/labextension/src/widgets/LeftPanel.tsx b/labextension/src/widgets/LeftPanel.tsx
index e90295b9a..bc5f7ac66 100644
--- a/labextension/src/widgets/LeftPanel.tsx
+++ b/labextension/src/widgets/LeftPanel.tsx
@@ -93,6 +93,41 @@ export class KubeflowKaleLeftPanel extends React.Component<IProps, IState> {
   // init state default values
   state = DefaultState;
 
+  // Return the notebook file name without extension (e.g. 'MyNotebook' from 'path/to/MyNotebook.ipynb')
+  getNotebookFileName = (notebook: NotebookPanel | null): string => {
+    if (!notebook || !notebook.context || !notebook.context.path) {
+      return '';
+    }
+    const path = notebook.context.path as string;
+    const base = path.split('/').pop() || '';
+    return base.replace(/\.ipynb$/i, '');
+  };
+
+  // Sanitize a name to match the pipeline name regex:
+  // '^[a-z0-9]([-a-z0-9]*[a-z0-9])?$'
+  // Steps:
+  // - lowercase
+  // - replace invalid chars with '-'
+  // - collapse multiple '-' into one
+  // - trim leading/trailing '-'
+  // - if result is empty, return a fallback unique name
+  sanitizePipelineName = (name: string): string => {
+    if (!name) return '';
+    let s = name.toLowerCase();
+    // replace any char that is not [a-z0-9-] with '-'
+    s = s.replace(/[^a-z0-9-]+/g, '-');
+    // collapse multiple hyphens
+    s = s.replace(/-+/g, '-');
+    // trim leading/trailing hyphens
+    s = s.replace(/^-+|-+$/g, '');
+    // ensure it starts and ends with alphanumeric; if not, fallback
+    if (!/^[a-z0-9].*[a-z0-9]$/.test(s)) {
+      // fallback: use a predictable but unique name
+      return 'pipeline-' + Date.now().toString(36);
+    }
+    return s;
+  };
+
   getActiveNotebook = (): NotebookPanel | null => {
     return this.props.tracker.currentWidget;
   };
@@ -318,11 +353,19 @@ export class KubeflowKaleLeftPanel extends React.Component<IProps, IState> {
           }
         }
 
+        // Use notebook filename as default pipeline name when not provided in metadata
+        const defaultPipelineName = this.getNotebookFileName(notebook);
+        const sanitizedDefaultPipelineName = this.sanitizePipelineName(
+          defaultPipelineName
+        );
         const metadata: IKaleNotebookMetadata = {
           ...notebookMetadata,
           experiment: experiment,
           experiment_name: experiment_name,
-          pipeline_name: notebookMetadata['pipeline_name'] || '',
+          pipeline_name:
+            notebookMetadata['pipeline_name'] && notebookMetadata['pipeline_name'] !== ''
+              ? notebookMetadata['pipeline_name']
+              : sanitizedDefaultPipelineName,
           pipeline_description: notebookMetadata['pipeline_description'] || '',
           docker_image:
             notebookMetadata['docker_image'] ||
@@ -333,11 +376,17 @@ export class KubeflowKaleLeftPanel extends React.Component<IProps, IState> {
           metadata: metadata
         });
       } else {
+        // If no notebook metadata exists, set pipeline_name to the sanitized notebook filename
+        const defaultPipelineName = this.getNotebookFileName(notebook);
+        const sanitizedDefaultPipelineName = this.sanitizePipelineName(
+          defaultPipelineName
+        );
         this.setState(prevState => ({
           metadata: {
             ...DefaultState.metadata,
             experiment: prevState.metadata.experiment,
-            experiment_name: prevState.metadata.experiment_name
+            experiment_name: prevState.metadata.experiment_name,
+            pipeline_name: sanitizedDefaultPipelineName
           }
         }));
       }

From 20bdb69ea59c2aad06326ddbf3ba405cdffe5f5b Mon Sep 17 00:00:00 2001
From: cordeirops <pedro.sbarainicordeiro@gmail.com>
Date: Wed, 19 Nov 2025 22:20:43 -0300
Subject: [PATCH 02/12] Fix code format

Signed-off-by: cordeirops <pedro.sbarainicordeiro@gmail.com>
---
 backend/kale/errors.py                 |  1 +
 labextension/src/widgets/LeftPanel.tsx | 13 ++++++-------
 2 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/backend/kale/errors.py b/backend/kale/errors.py
index 9d689b250..3afdda157 100644
--- a/backend/kale/errors.py
+++ b/backend/kale/errors.py
@@ -6,6 +6,7 @@
 
 class TaskMissingError(Exception):
     """Raised when a Pipeline has no steps/tasks.
+
     This is a domain-level exception and will be mapped to an RPC error
     (RPCTaskIsMissing) by the RPC handler.
     """
diff --git a/labextension/src/widgets/LeftPanel.tsx b/labextension/src/widgets/LeftPanel.tsx
index bc5f7ac66..8751aec73 100644
--- a/labextension/src/widgets/LeftPanel.tsx
+++ b/labextension/src/widgets/LeftPanel.tsx
@@ -355,15 +355,15 @@ export class KubeflowKaleLeftPanel extends React.Component<IProps, IState> {
 
         // Use notebook filename as default pipeline name when not provided in metadata
         const defaultPipelineName = this.getNotebookFileName(notebook);
-        const sanitizedDefaultPipelineName = this.sanitizePipelineName(
-          defaultPipelineName
-        );
+        const sanitizedDefaultPipelineName =
+          this.sanitizePipelineName(defaultPipelineName);
         const metadata: IKaleNotebookMetadata = {
           ...notebookMetadata,
           experiment: experiment,
           experiment_name: experiment_name,
           pipeline_name:
-            notebookMetadata['pipeline_name'] && notebookMetadata['pipeline_name'] !== ''
+            notebookMetadata['pipeline_name'] &&
+            notebookMetadata['pipeline_name'] !== ''
               ? notebookMetadata['pipeline_name']
               : sanitizedDefaultPipelineName,
           pipeline_description: notebookMetadata['pipeline_description'] || '',
@@ -378,9 +378,8 @@ export class KubeflowKaleLeftPanel extends React.Component<IProps, IState> {
       } else {
         // If no notebook metadata exists, set pipeline_name to the sanitized notebook filename
         const defaultPipelineName = this.getNotebookFileName(notebook);
-        const sanitizedDefaultPipelineName = this.sanitizePipelineName(
-          defaultPipelineName
-        );
+        const sanitizedDefaultPipelineName =
+          this.sanitizePipelineName(defaultPipelineName);
         this.setState(prevState => ({
           metadata: {
             ...DefaultState.metadata,

From 5bffb89506c153be5b789610210c748342ef3888 Mon Sep 17 00:00:00 2001
From: cordeirops <pedro.sbarainicordeiro@gmail.com>
Date: Wed, 19 Nov 2025 22:22:38 -0300
Subject: [PATCH 03/12] Fix code format

Signed-off-by: cordeirops <pedro.sbarainicordeiro@gmail.com>
---
 backend/kale/errors.py | 1 +
 1 file changed, 1 insertion(+)

diff --git a/backend/kale/errors.py b/backend/kale/errors.py
index 3afdda157..c7ab98c64 100644
--- a/backend/kale/errors.py
+++ b/backend/kale/errors.py
@@ -1,4 +1,5 @@
 """Core domain exceptions for Kale (non-RPC).
+
 Keep domain-specific exceptions here so core modules (compiler, processor)
 can raise them without depending on RPC layer.
 """

From 89e56fd1b535499f556f429d297e64b3e572e055 Mon Sep 17 00:00:00 2001
From: cordeirops <pedro.sbarainicordeiro@gmail.com>
Date: Wed, 19 Nov 2025 22:25:58 -0300
Subject: [PATCH 04/12] Fix lint check

Signed-off-by: cordeirops <pedro.sbarainicordeiro@gmail.com>
---
 labextension/src/widgets/LeftPanel.tsx | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/labextension/src/widgets/LeftPanel.tsx b/labextension/src/widgets/LeftPanel.tsx
index 8751aec73..506f51ee2 100644
--- a/labextension/src/widgets/LeftPanel.tsx
+++ b/labextension/src/widgets/LeftPanel.tsx
@@ -112,7 +112,7 @@ export class KubeflowKaleLeftPanel extends React.Component<IProps, IState> {
   // - trim leading/trailing '-'
   // - if result is empty, return a fallback unique name
   sanitizePipelineName = (name: string): string => {
-    if (!name) return '';
+    if (!name) {return '';}
     let s = name.toLowerCase();
     // replace any char that is not [a-z0-9-] with '-'
     s = s.replace(/[^a-z0-9-]+/g, '-');

From 4e0d52384745d98aa1dc5999d14f9fc47ba9af2d Mon Sep 17 00:00:00 2001
From: cordeirops <pedro.sbarainicordeiro@gmail.com>
Date: Wed, 19 Nov 2025 22:29:32 -0300
Subject: [PATCH 05/12] Fix lint check

Signed-off-by: cordeirops <pedro.sbarainicordeiro@gmail.com>
---
 labextension/src/widgets/LeftPanel.tsx | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/labextension/src/widgets/LeftPanel.tsx b/labextension/src/widgets/LeftPanel.tsx
index 506f51ee2..5df376920 100644
--- a/labextension/src/widgets/LeftPanel.tsx
+++ b/labextension/src/widgets/LeftPanel.tsx
@@ -112,7 +112,9 @@ export class KubeflowKaleLeftPanel extends React.Component<IProps, IState> {
   // - trim leading/trailing '-'
   // - if result is empty, return a fallback unique name
   sanitizePipelineName = (name: string): string => {
-    if (!name) {return '';}
+    if (!name) {
+      return '';
+    }
     let s = name.toLowerCase();
     // replace any char that is not [a-z0-9-] with '-'
     s = s.replace(/[^a-z0-9-]+/g, '-');

From bf5e734f0f6ac36f77837417c3807cb78b9b4073 Mon Sep 17 00:00:00 2001
From: cordeirops <pedro.sbarainicordeiro@gmail.com>
Date: Tue, 13 Jan 2026 17:20:40 -0300
Subject: [PATCH 06/12] Fix issues pointed out by Jesuino

Signed-off-by: cordeirops <pedro.sbarainicordeiro@gmail.com>
---
 labextension/src/lib/RPCUtils.tsx | 98 +++++++++++++++++--------------
 1 file changed, 55 insertions(+), 43 deletions(-)

diff --git a/labextension/src/lib/RPCUtils.tsx b/labextension/src/lib/RPCUtils.tsx
index 2cd5eaf61..4ad45a825 100644
--- a/labextension/src/lib/RPCUtils.tsx
+++ b/labextension/src/lib/RPCUtils.tsx
@@ -21,26 +21,35 @@ export const globalUnhandledRejection = async (event: any) => {
     // isolate the segments
     const stackLines = errorStack.split('\n');
     // create alert string
-    const alert_string = 'Unhandled Error'
+    const alert_string = 'Unhandled Error';
     // call the toast pop up
-    if (errorStack.includes('lab/extensions/')){
+    if (errorStack.includes('lab/extensions/')) {
       // if the error is caused by a jupyterlab extension, try to isolate the extension name
-      const extensionName = getExtensionName(stackLines)
+      const extensionName = getExtensionName(stackLines);
       Notification.error(`An unhandled error has been thrown.`, {
         actions: [
-          { label: 'Details', callback: () => NotebookUtils.showMessage(alert_string,
-            ["An unhandled error was thrown from:",
-              extensionName,
-              "Please see console for more details."
-            ]) }
+          {
+            label: 'Details',
+            callback: () =>
+              NotebookUtils.showMessage(alert_string, [
+                'An unhandled error was thrown from:',
+                extensionName,
+                'Please see console for more details.'
+              ])
+          }
         ],
         autoClose: 3000
       });
     } else {
       Notification.error(`An unhandled error has been thrown.`, {
         actions: [
-          { label: 'Details', callback: () => NotebookUtils.showMessage(alert_string,
-            ["Please see console for more details."]) }
+          {
+            label: 'Details',
+            callback: () =>
+              NotebookUtils.showMessage(alert_string, [
+                'Please see console for more details.'
+              ])
+          }
         ],
         autoClose: 3000
       });
@@ -48,9 +57,9 @@ export const globalUnhandledRejection = async (event: any) => {
   }
 };
 
-function getExtensionName(stackLines: Array<string>){
-  const urlSplit = stackLines.slice(1,2).toString();
-  const extensionSplit = urlSplit.split('@').slice(1,2).toString();
+function getExtensionName(stackLines: Array<string>) {
+  const urlSplit = stackLines.slice(1, 2).toString();
+  const extensionSplit = urlSplit.split('@').slice(1, 2).toString();
   const extensionParts = extensionSplit.split('/');
   extensionParts.pop();
   const extensionName = extensionParts.join('/');
@@ -74,7 +83,7 @@ export enum RPC_CALL_STATUS {
   InternalError = 4,
   ServiceUnavailable = 5,
   UnhandledError = 6,
-  TaskIsMissing = 7,
+  TaskIsMissing = 7
 }
 
 const getRpcCodeName = (code: number) => {
@@ -98,6 +107,8 @@ const getRpcCodeName = (code: number) => {
   }
 };
 
+const OPEN_DOCS_LABEL = 'Open docs';
+
 export const rokErrorTooltip = (rokError: IRPCError) => {
   return (
     <React.Fragment>
@@ -126,12 +137,12 @@ export const executeRpc = async (
   env: Kernel.IKernelConnection | NotebookPanel,
   func: string,
   kwargs: any = {},
-  ctx: { nb_path: string | null } = { nb_path: null },
+  ctx: { nb_path: string | null } = { nb_path: null }
 ) => {
   const cmd: string =
     'from kale.rpc.run import run as __kale_rpc_run\n' +
     `__kale_rpc_result = __kale_rpc_run("${func}", '${serialize(
-      kwargs,
+      kwargs
     )}', '${serialize(ctx)}')`;
   console.log('Executing command: ' + cmd);
   const expressions = { result: '__kale_rpc_result' };
@@ -140,10 +151,10 @@ export const executeRpc = async (
     output =
       env instanceof NotebookPanel
         ? await NotebookUtils.sendKernelRequestFromNotebook(
-          env,
-          cmd,
-          expressions,
-        )
+            env,
+            cmd,
+            expressions
+          )
         : await NotebookUtils.sendKernelRequest(env, cmd, expressions);
   } catch (e) {
     if (typeof e === 'object' && e !== null) {
@@ -152,7 +163,7 @@ export const executeRpc = async (
         const error = {
           rpc: `${func}`,
           status: `${(e as IError).ename}: ${(e as IError).evalue}`,
-          output: (e as IError).traceback,
+          output: (e as IError).traceback
         };
         throw new KernelError(error);
       }
@@ -168,7 +179,7 @@ export const executeRpc = async (
     const error = {
       rpc: `${func}`,
       status: output.result.status,
-      output: output,
+      output: output
     };
     throw new KernelError(error);
   }
@@ -187,7 +198,7 @@ export const executeRpc = async (
       rpc: `${func}`,
       err_message: 'Failed to parse response as JSON',
       error: error,
-      jsonData: json_data,
+      jsonData: json_data
     };
     throw new JSONParseError(jsonError);
   }
@@ -199,12 +210,11 @@ export const executeRpc = async (
       err_message: parsedResult.err_message,
       err_details: parsedResult.err_details,
       err_cls: parsedResult.err_cls,
-      trans_id: parsedResult.trans_id,
+      trans_id: parsedResult.trans_id
     };
     throw new RPCError(error);
   }
   return parsedResult.result;
-
 };
 
 export const showError = async (
@@ -215,11 +225,11 @@ export const showError = async (
   refresh: boolean = true,
   method: string | null = null,
   code: number | null = null,
-  trans_id: number | null = null,
+  trans_id: number | null = null
 ): Promise<void> => {
   const msg: string[] = [
     `Browser: ${navigator ? navigator.userAgent : 'other'}`,
-    `Type: ${type}`,
+    `Type: ${type}`
   ];
   if (method) {
     msg.push(`Method: ${method}()`);
@@ -241,7 +251,7 @@ export const showError = async (
 
 export const showRpcError = async (
   error: IRPCError,
-  refresh: boolean = false,
+  refresh: boolean = false
 ): Promise<void> => {
   if (error && error.code === RPC_CALL_STATUS.TaskIsMissing) {
     return await handleMissingPipelineStep(error);
@@ -255,7 +265,7 @@ export const showRpcError = async (
     refresh,
     error.rpc,
     error.code,
-    error.trans_id,
+    error.trans_id
   );
 };
 
@@ -265,7 +275,7 @@ export const _legacy_executeRpc = async (
   kernel: Kernel.IKernelConnection,
   func: string,
   args: any = {},
-  nb_path: string | null = null,
+  nb_path: string | null = null
 ) => {
   if (!nb_path && notebook) {
     nb_path = notebook.context.path;
@@ -298,7 +308,7 @@ export const _legacy_executeRpcAndShowRPCError = async (
   kernel: Kernel.IKernelConnection,
   func: string,
   args: any = {},
-  nb_path: string | null = null,
+  nb_path: string | null = null
 ) => {
   try {
     const result = await _legacy_executeRpc(
@@ -306,7 +316,7 @@ export const _legacy_executeRpcAndShowRPCError = async (
       kernel,
       func,
       args,
-      nb_path,
+      nb_path
     );
     return result;
   } catch (error) {
@@ -319,7 +329,10 @@ export const _legacy_executeRpcAndShowRPCError = async (
 };
 
 export abstract class BaseError extends Error {
-  constructor(message: string, public error: any) {
+  constructor(
+    message: string,
+    public error: any
+  ) {
     super(message);
     this.name = this.constructor.name;
     this.stack = new Error(message).stack;
@@ -343,7 +356,7 @@ export class KernelError extends BaseError {
       this.error.status,
       JSON.stringify(this.error.output, null, 3),
       refresh,
-      this.error.rpc,
+      this.error.rpc
     );
   }
 }
@@ -361,7 +374,7 @@ export class JSONParseError extends BaseError {
       this.error.error.message,
       this.error.json_data,
       refresh,
-      this.error.rpc,
+      this.error.rpc
     );
   }
 }
@@ -377,7 +390,6 @@ export class RPCError extends BaseError {
   }
 }
 
-
 /**
  * handleMissingPipelineStep - Async handler for missing pipeline step RPC errors.
  *
@@ -402,7 +414,7 @@ async function handleMissingPipelineStep(error: IRPCError) {
     '',
     `Details: ${error.err_details}`,
     '',
-    'You can fix this by tagging a code cell as a pipeline step (e.g. using the Left Panel), or by setting the notebook metadata `steps_defaults` to a list with the step name(s).',
+    'You can fix this by tagging a code cell as a pipeline step (via the cell edit/pencil icon), or by setting the notebook metadata steps_defaults to a list with the step name(s).'
   ];
   const body = (
     <div className="dialog-body">
@@ -411,23 +423,23 @@ async function handleMissingPipelineStep(error: IRPCError) {
           <SanitizedHTML
             allowedAttributes={{ a: ['href'] }}
             allowedTags={['b', 'i', 'em', 'strong', 'a', 'pre']}
-            html={s} />
+            html={s}
+          />
           <br />
         </React.Fragment>
       ))}
     </div>
   );
   const buttons: ReadonlyArray<Dialog.IButton> = [
-    Dialog.okButton({ label: 'Open docs' }),
-    Dialog.cancelButton({ label: 'Close' }),
+    Dialog.okButton({ label: OPEN_DOCS_LABEL }),
+    Dialog.cancelButton({ label: 'Close' })
   ];
   const result = await showDialog({ title, body, buttons });
   const clicked = result.button ? (result.button.label as string) : '';
-  if (clicked === 'Open docs') {
+  if (clicked === OPEN_DOCS_LABEL) {
     // Open the documentation in a new tab (repo README as fallback)
-    const docsUrl = 'https://github.com/kubeflow-kale/kale#readme';
+    const docsUrl = 'https://github.com/kubeflow/kale#readme';
     window.open(docsUrl, '_blank');
   }
   return;
 }
-

From d95a5f806ba112f0687e7dfacb669378009cd48d Mon Sep 17 00:00:00 2001
From: cordeirops <pedro.sbarainicordeiro@gmail.com>
Date: Wed, 4 Feb 2026 14:28:54 -0300
Subject: [PATCH 07/12] Fix issues pointed out by Hannah

Signed-off-by: cordeirops <pedro.sbarainicordeiro@gmail.com>
---
 backend/kale/compiler.py            |  8 ++--
 backend/kale/errors.py              | 14 -------
 backend/kale/rpc/errors.py          |  7 ----
 backend/kale/rpc/nb.py              | 32 ++++++----------
 examples/base/Untitled.ipynb        | 33 +++++++++++++++++
 examples/base/candies_sharing.ipynb |  2 +-
 labextension/src/lib/RPCUtils.tsx   | 57 ++++-------------------------
 7 files changed, 56 insertions(+), 97 deletions(-)
 delete mode 100644 backend/kale/errors.py
 create mode 100644 examples/base/Untitled.ipynb

diff --git a/backend/kale/compiler.py b/backend/kale/compiler.py
index 792e0dfb2..2378382d1 100644
--- a/backend/kale/compiler.py
+++ b/backend/kale/compiler.py
@@ -12,7 +12,7 @@
 from kale import __version__ as KALE_VERSION
 from kale.pipeline import Pipeline, Step, PipelineParam
 from kale.common import kfputils, utils, graphutils
-from kale.errors import TaskMissingError
+
 
 log = logging.getLogger(__name__)
 
@@ -90,11 +90,9 @@ def generate_dsl(self):
 
         Returns (str): A Python executable script
         """
-        # Fail early if there are no steps in the pipeline. Raise a domain-
-        # specific exception so higher layers (RPC) can map it to an RPC
-        # error without coupling core to the RPC layer.
+        # Fail early if there are no steps in the pipeline.
         if not hasattr(self.pipeline, 'steps') or not self.pipeline.steps:
-            raise TaskMissingError('Task is missing from pipeline.')
+            raise ValueError('Task is missing from pipeline.')
 
         # List of lightweight components generated code
         lightweight_components = [
diff --git a/backend/kale/errors.py b/backend/kale/errors.py
deleted file mode 100644
index c7ab98c64..000000000
--- a/backend/kale/errors.py
+++ /dev/null
@@ -1,14 +0,0 @@
-"""Core domain exceptions for Kale (non-RPC).
-
-Keep domain-specific exceptions here so core modules (compiler, processor)
-can raise them without depending on RPC layer.
-"""
-
-
-class TaskMissingError(Exception):
-    """Raised when a Pipeline has no steps/tasks.
-
-    This is a domain-level exception and will be mapped to an RPC error
-    (RPCTaskIsMissing) by the RPC handler.
-    """
-    pass
diff --git a/backend/kale/rpc/errors.py b/backend/kale/rpc/errors.py
index 204c203c5..3d1e81fe0 100644
--- a/backend/kale/rpc/errors.py
+++ b/backend/kale/rpc/errors.py
@@ -16,7 +16,6 @@ class Code(enum.Enum):
     INTERNAL_ERROR = 4
     SERVICE_UNAVAILABLE = 5
     UNHANDLED_ERROR = 6
-    TASK_IS_MISSING = 7
 
 
 class _RPCError(Exception):
@@ -77,12 +76,6 @@ class RPCServiceUnavailableError(_RPCError):
     message = "Service is Unavailable"
 
 
-class RPCTaskIsMissing(_RPCError):
-    """Task is missing from pipeline, you must add a pipeline step."""
-
-    name = "taskIsMissing"
-    code = Code.TASK_IS_MISSING
-    message = "Task is missing from pipeline, you must add a pipeline step."
 
 
 class RPCUnhandledError(_RPCError):
diff --git a/backend/kale/rpc/nb.py b/backend/kale/rpc/nb.py
index 2e201a6be..10bd9fc66 100644
--- a/backend/kale/rpc/nb.py
+++ b/backend/kale/rpc/nb.py
@@ -10,8 +10,7 @@
 from kale import marshal
 from kale.rpc.log import create_adapter
 from kale import Compiler, NotebookProcessor
-from kale.rpc.errors import RPCInternalError, RPCTaskIsMissing
-from kale.errors import TaskMissingError
+from kale.rpc.errors import RPCInternalError, RPCUnhandledError
 from kale.common import podutils, kfputils, kfutils, astutils
 
 KALE_MARSHAL_DIR_POSTFIX = ".kale.marshal.dir"
@@ -99,28 +98,19 @@ def compile_notebook(request, source_notebook_path,
 
         return {"pipeline_package_path": os.path.relpath(package_path),
                 "pipeline_metadata": pipeline.config.to_dict()}
-    except TaskMissingError as e:
-        # Domain-specific exception raised by core components when no
-        # pipeline steps are present. Map it to a specific RPC error so the
-        # frontend receives a concrete error code and message. Provide a
-        # slightly more actionable `details` field so the UI can display
-        # guidance to the user about how to fix the issue (e.g., tag a
-        # cell as a step or set `steps_defaults` in metadata).
-        msg = str(e)
-        request.log.exception("TaskMissingError during notebook "
-                              "compilation: %s", msg)
-        raise RPCTaskIsMissing(details=msg, trans_id=request.trans_id)
     except ValueError as e:
-        # kfp.compiler or graph_component may
-        # raise ValueError for other
-        # reasons; map them to an internal
-        # RPC error (unless they match the
-        # specific message — kept for backward compatibility).
         msg = str(e)
-        request.log.exception("ValueError during notebook"
-                              " compilation: %s", msg)
+        request.log.exception("ValueError during notebook compilation: %s", msg)
         if 'Task is missing from pipeline' in msg:
-            raise RPCTaskIsMissing(details=msg, trans_id=request.trans_id)
+            # Provide guidance to the user about how to fix the issue.
+            raise RPCUnhandledError(
+                details=(
+                    "The pipeline does not have any steps. "
+                    "Please tag a cell as a pipeline step or set "
+                    "`steps_defaults` in the notebook metadata."
+                ),
+                trans_id=request.trans_id
+            )
         raise RPCInternalError(details=msg, trans_id=request.trans_id)
     except Exception as e:
         # Let the run dispatcher handle generic exceptions as unhandled,
diff --git a/examples/base/Untitled.ipynb b/examples/base/Untitled.ipynb
new file mode 100644
index 000000000..daf492bd3
--- /dev/null
+++ b/examples/base/Untitled.ipynb
@@ -0,0 +1,33 @@
+{
+ "cells": [
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "d84421b3-217c-4d37-8b38-2ca7f7967f45",
+   "metadata": {},
+   "outputs": [],
+   "source": []
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 3 (ipykernel)",
+   "language": "python",
+   "name": "python3"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 3
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython3",
+   "version": "3.10.19"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 5
+}
diff --git a/examples/base/candies_sharing.ipynb b/examples/base/candies_sharing.ipynb
index 87f718358..1cfad349d 100644
--- a/examples/base/candies_sharing.ipynb
+++ b/examples/base/candies_sharing.ipynb
@@ -207,7 +207,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.10.18"
+   "version": "3.10.19"
   }
  },
  "nbformat": 4,
diff --git a/labextension/src/lib/RPCUtils.tsx b/labextension/src/lib/RPCUtils.tsx
index 4ad45a825..0fb4b37a2 100644
--- a/labextension/src/lib/RPCUtils.tsx
+++ b/labextension/src/lib/RPCUtils.tsx
@@ -8,7 +8,7 @@ import NotebookUtils from './NotebookUtils';
 // @ts-expect-error This module is not typed
 import SanitizedHTML from 'react-sanitized-html';
 import { isError, IError, IOutput } from '@jupyterlab/nbformat';
-import { Notification, Dialog, showDialog } from '@jupyterlab/apputils';
+import { Notification } from '@jupyterlab/apputils';
 
 export const globalUnhandledRejection = async (event: any) => {
   console.error(event.reason);
@@ -82,8 +82,7 @@ export enum RPC_CALL_STATUS {
   NotFound = 3,
   InternalError = 4,
   ServiceUnavailable = 5,
-  UnhandledError = 6,
-  TaskIsMissing = 7
+  UnhandledError = 6
 }
 
 const getRpcCodeName = (code: number) => {
@@ -100,14 +99,12 @@ const getRpcCodeName = (code: number) => {
       return 'InternalError';
     case RPC_CALL_STATUS.ServiceUnavailable:
       return 'ServiceUnavailable';
-    case RPC_CALL_STATUS.TaskIsMissing:
-      return 'TaskIsMissing';
     default:
       return 'UnhandledError';
   }
 };
 
-const OPEN_DOCS_LABEL = 'Open docs';
+
 
 export const rokErrorTooltip = (rokError: IRPCError) => {
   return (
@@ -151,10 +148,10 @@ export const executeRpc = async (
     output =
       env instanceof NotebookPanel
         ? await NotebookUtils.sendKernelRequestFromNotebook(
-            env,
-            cmd,
-            expressions
-          )
+          env,
+          cmd,
+          expressions
+        )
         : await NotebookUtils.sendKernelRequest(env, cmd, expressions);
   } catch (e) {
     if (typeof e === 'object' && e !== null) {
@@ -253,9 +250,6 @@ export const showRpcError = async (
   error: IRPCError,
   refresh: boolean = false
 ): Promise<void> => {
-  if (error && error.code === RPC_CALL_STATUS.TaskIsMissing) {
-    return await handleMissingPipelineStep(error);
-  }
 
   await showError(
     'An RPC Error has occurred',
@@ -407,39 +401,4 @@ export class RPCError extends BaseError {
  *          user clicked "Open docs", the documentation page will be opened
  *          in a new tab as a fallback/help resource.
  */
-async function handleMissingPipelineStep(error: IRPCError) {
-  const title = 'Pipeline step missing';
-  const bodyLines = [
-    `Message: ${error.err_message}`,
-    '',
-    `Details: ${error.err_details}`,
-    '',
-    'You can fix this by tagging a code cell as a pipeline step (via the cell edit/pencil icon), or by setting the notebook metadata steps_defaults to a list with the step name(s).'
-  ];
-  const body = (
-    <div className="dialog-body">
-      {bodyLines.map((s: string, i: number) => (
-        <React.Fragment key={`msg-${i}`}>
-          <SanitizedHTML
-            allowedAttributes={{ a: ['href'] }}
-            allowedTags={['b', 'i', 'em', 'strong', 'a', 'pre']}
-            html={s}
-          />
-          <br />
-        </React.Fragment>
-      ))}
-    </div>
-  );
-  const buttons: ReadonlyArray<Dialog.IButton> = [
-    Dialog.okButton({ label: OPEN_DOCS_LABEL }),
-    Dialog.cancelButton({ label: 'Close' })
-  ];
-  const result = await showDialog({ title, body, buttons });
-  const clicked = result.button ? (result.button.label as string) : '';
-  if (clicked === OPEN_DOCS_LABEL) {
-    // Open the documentation in a new tab (repo README as fallback)
-    const docsUrl = 'https://github.com/kubeflow/kale#readme';
-    window.open(docsUrl, '_blank');
-  }
-  return;
-}
+

From 49f230acd983ddd7ae13fc8f944542884a160398 Mon Sep 17 00:00:00 2001
From: cordeirops <pedro.sbarainicordeiro@gmail.com>
Date: Wed, 4 Feb 2026 15:33:38 -0300
Subject: [PATCH 08/12] Fix backend lint and frontend syntax errors

Signed-off-by: cordeirops <pedro.sbarainicordeiro@gmail.com>
---
 backend/kale/compiler.py          |  7 ++++---
 labextension/src/lib/RPCUtils.tsx | 20 ++------------------
 2 files changed, 6 insertions(+), 21 deletions(-)

diff --git a/backend/kale/compiler.py b/backend/kale/compiler.py
index 2378382d1..540e9acec 100644
--- a/backend/kale/compiler.py
+++ b/backend/kale/compiler.py
@@ -1,12 +1,13 @@
 # SPDX-License-Identifier: Apache-2.0
 # Copyright (c) 2019–2025 The Kale Contributors.
 
+import argparse
+import logging
 import os
 import re
-import logging
-import argparse
-import autopep8
 from typing import NamedTuple
+
+import autopep8
 from jinja2 import Environment, PackageLoader, FileSystemLoader
 
 from kale import __version__ as KALE_VERSION
diff --git a/labextension/src/lib/RPCUtils.tsx b/labextension/src/lib/RPCUtils.tsx
index 0fb4b37a2..aa9ed0895 100644
--- a/labextension/src/lib/RPCUtils.tsx
+++ b/labextension/src/lib/RPCUtils.tsx
@@ -47,6 +47,8 @@ export const globalUnhandledRejection = async (event: any) => {
             label: 'Details',
             callback: () =>
               NotebookUtils.showMessage(alert_string, [
+                'An unhandled error was thrown from:',
+                extensionName,
                 'Please see console for more details.'
               ])
           }
@@ -384,21 +386,3 @@ export class RPCError extends BaseError {
   }
 }
 
-/**
- * handleMissingPipelineStep - Async handler for missing pipeline step RPC errors.
- *
- * Displays a modal dialog that informs the user that a pipeline step is missing,
- * shows the RPC-provided message and details, and suggests remediation steps:
- * tagging a code cell as a pipeline step or setting the notebook metadata
- * `steps_defaults` to include the step name(s). The dialog body is rendered as
- * sanitized HTML with a restricted set of allowed tags and attributes to avoid
- * injection issues. The dialog offers two buttons: "Open docs" and "Close".
- * Selecting "Open docs" opens the Kale README/docs page in a new browser tab.
- *
- * @param error - The IRPCError instance containing `err_message` and `err_details`
- *                to present in the dialog body.
- * @returns A Promise that resolves once the user dismisses the dialog. If the
- *          user clicked "Open docs", the documentation page will be opened
- *          in a new tab as a fallback/help resource.
- */
-

From 8cbdb0f6cd7251b1994723eb7d34c5ad5f9dce9f Mon Sep 17 00:00:00 2001
From: cordeirops <pedro.sbarainicordeiro@gmail.com>
Date: Wed, 4 Feb 2026 15:34:43 -0300
Subject: [PATCH 09/12] FIx problems

Signed-off-by: cordeirops <pedro.sbarainicordeiro@gmail.com>
---
 backend/kale/rpc/nb.py       |  9 ++++-----
 examples/base/Untitled.ipynb | 33 ---------------------------------
 2 files changed, 4 insertions(+), 38 deletions(-)
 delete mode 100644 examples/base/Untitled.ipynb

diff --git a/backend/kale/rpc/nb.py b/backend/kale/rpc/nb.py
index 10bd9fc66..775203de5 100644
--- a/backend/kale/rpc/nb.py
+++ b/backend/kale/rpc/nb.py
@@ -1,17 +1,16 @@
 # SPDX-License-Identifier: Apache-2.0
 # Copyright (c) 2019–2025 The Kale Contributors.
 
+import logging
 import os
 import shutil
-import logging
 
 from tabulate import tabulate
 
-from kale import marshal
-from kale.rpc.log import create_adapter
-from kale import Compiler, NotebookProcessor
+from kale import Compiler, NotebookProcessor, marshal
+from kale.common import astutils, kfputils, podutils
 from kale.rpc.errors import RPCInternalError, RPCUnhandledError
-from kale.common import podutils, kfputils, kfutils, astutils
+from kale.rpc.log import create_adapter
 
 KALE_MARSHAL_DIR_POSTFIX = ".kale.marshal.dir"
 KALE_PIPELINE_STEP_ENV = "KALE_PIPELINE_STEP"
diff --git a/examples/base/Untitled.ipynb b/examples/base/Untitled.ipynb
deleted file mode 100644
index daf492bd3..000000000
--- a/examples/base/Untitled.ipynb
+++ /dev/null
@@ -1,33 +0,0 @@
-{
- "cells": [
-  {
-   "cell_type": "code",
-   "execution_count": null,
-   "id": "d84421b3-217c-4d37-8b38-2ca7f7967f45",
-   "metadata": {},
-   "outputs": [],
-   "source": []
-  }
- ],
- "metadata": {
-  "kernelspec": {
-   "display_name": "Python 3 (ipykernel)",
-   "language": "python",
-   "name": "python3"
-  },
-  "language_info": {
-   "codemirror_mode": {
-    "name": "ipython",
-    "version": 3
-   },
-   "file_extension": ".py",
-   "mimetype": "text/x-python",
-   "name": "python",
-   "nbconvert_exporter": "python",
-   "pygments_lexer": "ipython3",
-   "version": "3.10.19"
-  }
- },
- "nbformat": 4,
- "nbformat_minor": 5
-}

From feb29d565f10d67ad0521ed4c003c1fb48a30b77 Mon Sep 17 00:00:00 2001
From: Pedro Sbaraini Cordeiro <pedro.sbarainicordeiro@gmail.com>
Date: Wed, 4 Feb 2026 15:44:14 -0300
Subject: [PATCH 10/12] Add extension name retrieval for error notifications

Signed-off-by: cordeirops <pedro.sbarainicordeiro@gmail.com>
---
 labextension/src/lib/RPCUtils.tsx | 1 +
 1 file changed, 1 insertion(+)

diff --git a/labextension/src/lib/RPCUtils.tsx b/labextension/src/lib/RPCUtils.tsx
index 73ad0d430..b0c7dca27 100644
--- a/labextension/src/lib/RPCUtils.tsx
+++ b/labextension/src/lib/RPCUtils.tsx
@@ -48,6 +48,7 @@ export const globalUnhandledRejection = async (event: any) => {
         autoClose: 3000
       });
     } else {
+      const extensionName = getExtensionName(stackLines);
       Notification.error(`An unhandled error has been thrown.`, {
         actions: [
           {

From 4e4d4663d9dff6e35aa73126ecda90459ee5a5fc Mon Sep 17 00:00:00 2001
From: cordeirops <pedro.sbarainicordeiro@gmail.com>
Date: Wed, 4 Feb 2026 15:59:56 -0300
Subject: [PATCH 11/12] FIx lint errors

Signed-off-by: cordeirops <pedro.sbarainicordeiro@gmail.com>
---
 backend/kale/compiler.py               | 1 -
 labextension/src/widgets/LeftPanel.tsx | 4 ++--
 2 files changed, 2 insertions(+), 3 deletions(-)

diff --git a/backend/kale/compiler.py b/backend/kale/compiler.py
index fb5e995fa..34ef06138 100644
--- a/backend/kale/compiler.py
+++ b/backend/kale/compiler.py
@@ -25,7 +25,6 @@
 from kale.common import graphutils, kfputils, utils
 from kale.pipeline import Pipeline, PipelineParam, Step
 
-
 log = logging.getLogger(__name__)
 
 PY_FN_TEMPLATE = "py_function_template.jinja2"
diff --git a/labextension/src/widgets/LeftPanel.tsx b/labextension/src/widgets/LeftPanel.tsx
index 968b5883c..c56a785e6 100644
--- a/labextension/src/widgets/LeftPanel.tsx
+++ b/labextension/src/widgets/LeftPanel.tsx
@@ -397,8 +397,8 @@ export class KubeflowKaleLeftPanel extends React.Component<IProps, IState> {
             ...DefaultState.metadata,
             experiment: prevState.metadata.experiment,
             experiment_name: prevState.metadata.experiment_name,
-            pipeline_name: sanitizedDefaultPipelineName
-          }
+            pipeline_name: sanitizedDefaultPipelineName,
+          },
         }));
       }
     } else {

From 7dd496e6856b8f8dc5144c81b6439eac5f584f9e Mon Sep 17 00:00:00 2001
From: cordeirops <pedro.sbarainicordeiro@gmail.com>
Date: Wed, 4 Feb 2026 16:10:38 -0300
Subject: [PATCH 12/12] format backend with ruff

Signed-off-by: cordeirops <pedro.sbarainicordeiro@gmail.com>
---
 backend/kale/compiler.py   |  4 ++--
 backend/kale/rpc/errors.py |  2 --
 backend/kale/rpc/nb.py     | 19 +++++++++----------
 3 files changed, 11 insertions(+), 14 deletions(-)

diff --git a/backend/kale/compiler.py b/backend/kale/compiler.py
index 34ef06138..e20592c60 100644
--- a/backend/kale/compiler.py
+++ b/backend/kale/compiler.py
@@ -104,8 +104,8 @@ def generate_dsl(self):
         Returns (str): A Python executable script
         """
         # Fail early if there are no steps in the pipeline.
-        if not hasattr(self.pipeline, 'steps') or not self.pipeline.steps:
-            raise ValueError('Task is missing from pipeline.')
+        if not hasattr(self.pipeline, "steps") or not self.pipeline.steps:
+            raise ValueError("Task is missing from pipeline.")
 
         # List of lightweight components generated code
         lightweight_components = [
diff --git a/backend/kale/rpc/errors.py b/backend/kale/rpc/errors.py
index 1a19d4c87..7fc595e41 100644
--- a/backend/kale/rpc/errors.py
+++ b/backend/kale/rpc/errors.py
@@ -97,8 +97,6 @@ class RPCServiceUnavailableError(_RPCError):
     message = "Service is Unavailable"
 
 
-
-
 class RPCUnhandledError(_RPCError):
     """Unhandled RPC Error."""
 
diff --git a/backend/kale/rpc/nb.py b/backend/kale/rpc/nb.py
index 41faa387c..c0089991e 100644
--- a/backend/kale/rpc/nb.py
+++ b/backend/kale/rpc/nb.py
@@ -96,8 +96,7 @@ def get_base_image(request):
 def compile_notebook(request, source_notebook_path, notebook_metadata_overrides=None, debug=False):
     """Compile the notebook to KFP DSL."""
     try:
-        processor = NotebookProcessor(source_notebook_path,
-                                      notebook_metadata_overrides)
+        processor = NotebookProcessor(source_notebook_path, notebook_metadata_overrides)
         pipeline = processor.run()
         imports_and_functions = processor.get_imports_and_functions()
         script_path = Compiler(pipeline, imports_and_functions).compile()
@@ -108,15 +107,16 @@ def compile_notebook(request, source_notebook_path, notebook_metadata_overrides=
         instance.logger = request.log if
         hasattr(request, "log") else logger"""
 
-        package_path = kfputils.compile_pipeline(script_path,
-                                                 pipeline.config.pipeline_name)
+        package_path = kfputils.compile_pipeline(script_path, pipeline.config.pipeline_name)
 
-        return {"pipeline_package_path": os.path.relpath(package_path),
-                "pipeline_metadata": pipeline.config.to_dict()}
+        return {
+            "pipeline_package_path": os.path.relpath(package_path),
+            "pipeline_metadata": pipeline.config.to_dict(),
+        }
     except ValueError as e:
         msg = str(e)
         request.log.exception("ValueError during notebook compilation: %s", msg)
-        if 'Task is missing from pipeline' in msg:
+        if "Task is missing from pipeline" in msg:
             # Provide guidance to the user about how to fix the issue.
             raise RPCUnhandledError(
                 details=(
@@ -124,14 +124,13 @@ def compile_notebook(request, source_notebook_path, notebook_metadata_overrides=
                     "Please tag a cell as a pipeline step or set "
                     "`steps_defaults` in the notebook metadata."
                 ),
-                trans_id=request.trans_id
+                trans_id=request.trans_id,
             )
         raise RPCInternalError(details=msg, trans_id=request.trans_id)
     except Exception as e:
         # Let the run dispatcher handle generic exceptions as unhandled,
         # but log for debug purposes.
-        request.log.exception("Unexpected error during "
-                              "notebook compilation: %s", e)
+        request.log.exception("Unexpected error during notebook compilation: %s", e)
         raise