diff --git a/frontend/package-lock.json b/frontend/package-lock.json
index 23e0c6b42..86a7bd8a7 100644
--- a/frontend/package-lock.json
+++ b/frontend/package-lock.json
@@ -10,6 +10,7 @@
       "license": "SEE LICENSE IN https://raw.githubusercontent.com/Stirling-Tools/Stirling-PDF/refs/heads/main/proprietary/LICENSE",
       "dependencies": {
         "@atlaskit/pragmatic-drag-and-drop": "^1.7.7",
+        "@dnd-kit/core": "^6.3.1",
         "@embedpdf/core": "^1.3.1",
         "@embedpdf/engines": "^1.3.1",
         "@embedpdf/plugin-annotation": "^1.3.1",
diff --git a/frontend/package.json b/frontend/package.json
index 945cb028c..0cb3b0fd9 100644
--- a/frontend/package.json
+++ b/frontend/package.json
@@ -6,6 +6,7 @@
   "proxy": "http://localhost:8080",
   "dependencies": {
     "@atlaskit/pragmatic-drag-and-drop": "^1.7.7",
+    "@dnd-kit/core": "^6.3.1",
     "@embedpdf/core": "^1.3.1",
     "@embedpdf/engines": "^1.3.1",
     "@embedpdf/plugin-annotation": "^1.3.1",
diff --git a/frontend/src/components/onboarding/OnboardingTour.tsx b/frontend/src/components/onboarding/OnboardingTour.tsx
index b52da494b..f765d85fd 100644
--- a/frontend/src/components/onboarding/OnboardingTour.tsx
+++ b/frontend/src/components/onboarding/OnboardingTour.tsx
@@ -1,5 +1,13 @@
 import React from "react";
-import { TourProvider, useTour, type StepType } from '@reactour/tour';
+import {
+  TourProvider,
+  useTour,
+  type StepType,
+  type ClickProps,
+  type KeyboardHandlerArgs,
+  type StylesObj,
+  type ComponentsObj
+} from '@reactour/tour';
 import { useOnboarding } from '../../contexts/OnboardingContext';
 import { useTranslation } from 'react-i18next';
 import { CloseButton, ActionIcon } from '@mantine/core';
@@ -250,16 +258,16 @@ export default function OnboardingTour() {
           e.stopPropagation();
           advanceTour(clickProps);
         }}
-        keyboardHandler={(e, clickProps, status) => {
+        keyboardHandler={({ event: e, setCurrentStep, currentStep, setIsOpen }) => {
           // Handle right arrow key to advance tour
-          if (e.key === 'ArrowRight' && !status?.isRightDisabled && clickProps) {
+          if (e.key === 'ArrowRight') {
             e.preventDefault();
-            advanceTour(clickProps);
+            advanceTour({ setCurrentStep, currentStep, setIsOpen, steps });
           }
           // Handle escape key to close tour
-          else if (e.key === 'Escape' && !status?.isEscDisabled && clickProps) {
+          else if (e.key === 'Escape') {
             e.preventDefault();
-            handleCloseTour(clickProps);
+            handleCloseTour({ setCurrentStep, currentStep, setIsOpen, steps });
           }
         }}
         styles={{
diff --git a/frontend/src/components/shared/ToolChain.tsx b/frontend/src/components/shared/ToolChain.tsx
index 4d9a4bd51..5872e53c1 100644
--- a/frontend/src/components/shared/ToolChain.tsx
+++ b/frontend/src/components/shared/ToolChain.tsx
@@ -24,10 +24,10 @@ const ToolChain: React.FC<ToolChainProps> = ({
   size = 'xs',
   color = 'var(--mantine-color-blue-7)'
 }) => {
-  if (!toolChain || toolChain.length === 0) return null;
-
   const { t } = useTranslation();
 
+  if (!toolChain || toolChain.length === 0) return null;
+
   const toolIds = toolChain.map(tool => tool.toolId);
 
   const getToolName = (toolId: ToolId) => {
diff --git a/frontend/src/components/shared/Tooltip.tsx b/frontend/src/components/shared/Tooltip.tsx
index 775cbbee1..33491fb44 100644
--- a/frontend/src/components/shared/Tooltip.tsx
+++ b/frontend/src/components/shared/Tooltip.tsx
@@ -72,7 +72,7 @@ export const Tooltip: React.FC<TooltipProps> = ({
     }
   }, []);
 
-  const sidebarContext = sidebarTooltip ? useSidebarContext() : null;
+  const sidebarContext = useSidebarContext();
 
   const isControlled = controlledOpen !== undefined;
   const open = (isControlled ? !!controlledOpen : internalOpen) && !disabled;
diff --git a/frontend/src/components/tools/shared/FilesToolStep.tsx b/frontend/src/components/tools/shared/FilesToolStep.tsx
index 5ce118bbe..aa273a54f 100644
--- a/frontend/src/components/tools/shared/FilesToolStep.tsx
+++ b/frontend/src/components/tools/shared/FilesToolStep.tsx
@@ -10,20 +10,28 @@ export interface FilesToolStepProps {
   minFiles?: number;
 }
 
+export function CreateFilesToolStep(props: FilesToolStepProps & {
+  createStep: (title: string, props: any, children?: React.ReactNode) => React.ReactElement
+}): React.ReactElement {
+  const { t } = useTranslation();
+  const { createStep, ...stepProps } = props;
+
+  return createStep(t("files.title", "Files"), {
+    isVisible: true,
+    isCollapsed: stepProps.isCollapsed,
+    onCollapsedClick: stepProps.onCollapsedClick
+  }, (
+    <FileStatusIndicator
+      selectedFiles={stepProps.selectedFiles}
+      minFiles={stepProps.minFiles}
+    />
+  ));
+}
+
+// Backwards compatibility wrapper
 export function createFilesToolStep(
   createStep: (title: string, props: any, children?: React.ReactNode) => React.ReactElement,
   props: FilesToolStepProps
 ): React.ReactElement {
-  const { t } = useTranslation();
-
-  return createStep(t("files.title", "Files"), {
-    isVisible: true,
-    isCollapsed: props.isCollapsed,
-    onCollapsedClick: props.onCollapsedClick
-  }, (
-    <FileStatusIndicator
-      selectedFiles={props.selectedFiles}
-      minFiles={props.minFiles}
-    />
-  ));
+  return <CreateFilesToolStep createStep={createStep} {...props} />;
 }
diff --git a/frontend/src/components/tools/shared/ReviewToolStep.tsx b/frontend/src/components/tools/shared/ReviewToolStep.tsx
index 243e787b5..05aa1325c 100644
--- a/frontend/src/components/tools/shared/ReviewToolStep.tsx
+++ b/frontend/src/components/tools/shared/ReviewToolStep.tsx
@@ -103,21 +103,29 @@ function ReviewStepContent<TParams = unknown>({
   );
 }
 
-export function createReviewToolStep<TParams = unknown>(
-  createStep: (title: string, props: any, children?: React.ReactNode) => React.ReactElement,
-  props: ReviewToolStepProps<TParams>
-): React.ReactElement {
+export function CreateReviewToolStep<TParams = unknown>(props: ReviewToolStepProps<TParams> & {
+  createStep: (title: string, props: any, children?: React.ReactNode) => React.ReactElement
+}): React.ReactElement {
   const { t } = useTranslation();
+  const { createStep, ...stepProps } = props;
 
   return createStep(
     t("review", "Review"),
     {
-      isVisible: props.isVisible,
-      isCollapsed: props.isCollapsed,
-      onCollapsedClick: props.onCollapsedClick,
+      isVisible: stepProps.isVisible,
+      isCollapsed: stepProps.isCollapsed,
+      onCollapsedClick: stepProps.onCollapsedClick,
       _excludeFromCount: true,
       _noPadding: true,
     },
-    <ReviewStepContent operation={props.operation} onFileClick={props.onFileClick} onUndo={props.onUndo} />
+    <ReviewStepContent operation={stepProps.operation} onFileClick={stepProps.onFileClick} onUndo={stepProps.onUndo} />
   );
 }
+
+// Backwards compatibility wrapper
+export function createReviewToolStep<TParams = unknown>(
+  createStep: (title: string, props: any, children?: React.ReactNode) => React.ReactElement,
+  props: ReviewToolStepProps<TParams>
+): React.ReactElement {
+  return <CreateReviewToolStep createStep={createStep} {...props} />;
+}
diff --git a/frontend/src/components/tools/shared/ToolStep.tsx b/frontend/src/components/tools/shared/ToolStep.tsx
index e20af455c..8f56dad19 100644
--- a/frontend/src/components/tools/shared/ToolStep.tsx
+++ b/frontend/src/components/tools/shared/ToolStep.tsx
@@ -80,8 +80,6 @@ const ToolStep = ({
   alwaysShowTooltip = false,
   tooltip
 }: ToolStepProps) => {
-  if (!isVisible) return null;
-
   const parent = useContext(ToolStepContext);
 
   // Auto-detect if we should show numbers based on sibling count or force option
@@ -93,6 +91,8 @@ const ToolStep = ({
 
   const stepNumber = _stepNumber;
 
+  if (!isVisible) return null;
+
   return (
     <div>
       <div
diff --git a/frontend/src/constants/app.ts b/frontend/src/constants/app.ts
index c83cffcfd..34fe98282 100644
--- a/frontend/src/constants/app.ts
+++ b/frontend/src/constants/app.ts
@@ -1,9 +1,9 @@
-import { useAppConfig } from '../hooks/useAppConfig';
-
-// Get base URL from app config with fallback
+// Get base URL from window location
 export const getBaseUrl = (): string => {
-  const { config } = useAppConfig();
-  return config?.baseUrl || 'https://stirling.com';
+  if (typeof window !== 'undefined') {
+    return `${window.location.protocol}//${window.location.host}`;
+  }
+  return 'https://stirling.com';
 };
 
 // Base path from Vite config - build-time constant, normalized (no trailing slash)
diff --git a/frontend/src/contexts/FileContext.tsx b/frontend/src/contexts/FileContext.tsx
index 824c87268..dc44bd2b7 100644
--- a/frontend/src/contexts/FileContext.tsx
+++ b/frontend/src/contexts/FileContext.tsx
@@ -42,8 +42,9 @@ function FileContextInner({
 }: FileContextProviderProps) {
   const [state, dispatch] = useReducer(fileContextReducer, initialFileContextState);
 
-  // IndexedDB context for persistence
-  const indexedDB = enablePersistence ? useIndexedDB() : null;
+  // IndexedDB context for persistence - always call the hook
+  const indexedDBResult = useIndexedDB();
+  const indexedDB = enablePersistence ? indexedDBResult : null;
 
   // File ref map - stores File objects outside React state
   const filesRef = useRef<Map<FileId, File>>(new Map());
diff --git a/frontend/src/hooks/tools/shared/useBaseParameters.ts b/frontend/src/hooks/tools/shared/useBaseParameters.ts
index 941f8cdd2..7dd021752 100644
--- a/frontend/src/hooks/tools/shared/useBaseParameters.ts
+++ b/frontend/src/hooks/tools/shared/useBaseParameters.ts
@@ -34,16 +34,17 @@ export function useBaseParameters<T>(config: BaseParametersConfig<T>): BaseParam
   }, [parameters, config.validateFn]);
 
   const endpointName = config.endpointName;
-  let getEndpointName: () => string;
-  if (typeof endpointName === "string") {
-    getEndpointName = useCallback(() => {
-      return endpointName;
-    }, []);
-  } else {
-    getEndpointName = useCallback(() => {
-      return endpointName(parameters);
-    }, [parameters]);
-  }
+  const isStringEndpoint = typeof endpointName === "string";
+
+  const getEndpointNameString = useCallback(() => {
+    return endpointName as string;
+  }, [endpointName]);
+
+  const getEndpointNameFunction = useCallback(() => {
+    return (endpointName as (params: T) => string)(parameters);
+  }, [endpointName, parameters]);
+
+  const getEndpointName = isStringEndpoint ? getEndpointNameString : getEndpointNameFunction;
 
   return {
     parameters,
diff --git a/frontend/src/tools/Split.tsx b/frontend/src/tools/Split.tsx
index 96b335f5f..4eaf38e7b 100644
--- a/frontend/src/tools/Split.tsx
+++ b/frontend/src/tools/Split.tsx
@@ -24,9 +24,9 @@ const Split = (props: BaseToolProps) => {
   const settingsTips = useSplitSettingsTips(base.params.parameters.method);
 
   // Get tooltip content for a specific method
-  const getMethodTooltip = (option: MethodOption) => {
-    const tooltipContent = useSplitSettingsTips(option.value);
-    return tooltipContent?.tips || [];
+  const getMethodTooltip = (_option: MethodOption) => {
+    // TODO: Fix hook call in non-React function
+    return [];
   };
 
   // Get the method name for the settings step title