diff --git a/frontend/editor/src/core/pages/MobileScannerPage.tsx b/frontend/editor/src/core/pages/MobileScannerPage.tsx
index 0424125aa8..0d14ce7ee8 100644
--- a/frontend/editor/src/core/pages/MobileScannerPage.tsx
+++ b/frontend/editor/src/core/pages/MobileScannerPage.tsx
@@ -20,12 +20,32 @@ import PhotoCameraRoundedIcon from "@mui/icons-material/PhotoCameraRounded";
 import UploadRoundedIcon from "@mui/icons-material/UploadRounded";
 import AddPhotoAlternateRoundedIcon from "@mui/icons-material/AddPhotoAlternateRounded";
 import CheckCircleRoundedIcon from "@mui/icons-material/CheckCircleRounded";
-import { loadJscanify } from "@app/utils/loadJscanify";
+import {
+  loadJscanify,
+  type JscanifyCornerPoints,
+  type JscanifyScanner,
+} from "@app/utils/loadJscanify";
 import apiClient from "@app/services/apiClient";
 
 // Use the configured API base (e.g. api.stirling.com), not the page origin.
 const API_BASE = (apiClient.defaults.baseURL ?? "").replace(/\/+$/, "");
 
+// Experimental camera controls (W3C Image Capture / MediaStream extensions) that
+// are not yet part of the standard DOM lib typings but are widely shipped on
+// mobile browsers and required for document scanning.
+declare global {
+  interface MediaTrackCapabilities {
+    focusMode?: string[];
+    exposureMode?: string[];
+    torch?: boolean;
+  }
+  interface MediaTrackConstraintSet {
+    focusMode?: ConstrainDOMString;
+    exposureMode?: ConstrainDOMString;
+    torch?: ConstrainBoolean;
+  }
+}
+
 /**
  * MobileScannerPage
  *
@@ -63,7 +83,7 @@ export default function MobileScannerPage() {
   const highlightCanvasRef = useRef<HTMLCanvasElement>(null);
   const streamRef = useRef<MediaStream | null>(null);
   const fileInputRef = useRef<HTMLInputElement>(null);
-  const scannerRef = useRef<any>(null);
+  const scannerRef = useRef<JscanifyScanner | null>(null);
   const highlightIntervalRef = useRef<number | null>(null);
 
   // Detection resolution - extremely low for mobile performance
@@ -254,15 +274,15 @@ export default function MobileScannerPage() {
 
             // Configure camera capabilities for document scanning
             try {
-              const capabilities = videoTrack.getCapabilities() as any; // Cast to any for experimental camera APIs
-              const constraints: any = { advanced: [] };
+              const capabilities = videoTrack.getCapabilities();
+              const advanced: MediaTrackConstraintSet[] = [];
 
               // 1. Enable continuous autofocus
               if (
                 capabilities.focusMode &&
                 capabilities.focusMode.includes("continuous")
               ) {
-                constraints.advanced.push({ focusMode: "continuous" });
+                advanced.push({ focusMode: "continuous" });
                 console.log("✓ Continuous autofocus enabled");
               }
 
@@ -271,7 +291,7 @@ export default function MobileScannerPage() {
                 capabilities.exposureMode &&
                 capabilities.exposureMode.includes("continuous")
               ) {
-                constraints.advanced.push({ exposureMode: "continuous" });
+                advanced.push({ exposureMode: "continuous" });
                 console.log("✓ Auto-exposure enabled");
               }
 
@@ -282,8 +302,8 @@ export default function MobileScannerPage() {
               }
 
               // Apply all constraints
-              if (constraints.advanced.length > 0) {
-                await videoTrack.applyConstraints(constraints);
+              if (advanced.length > 0) {
+                await videoTrack.applyConstraints({ advanced });
               }
             } catch (err) {
               console.log("Could not configure camera features:", err);
@@ -444,15 +464,19 @@ export default function MobileScannerPage() {
 
               // Step 2: Simple jscanify detection
               const detectionStart = performance.now();
-              let corners = null;
+              let corners: JscanifyCornerPoints | null = null;
 
               // Run jscanify detection directly - convert canvas to Mat first
-              const mat = (window as any).cv.imread(detectionCanvas);
-              const contour = scannerRef.current.findPaperContour(mat);
-              mat.delete();
+              const cv = window.cv;
+              const scanner = scannerRef.current;
+              if (cv && scanner) {
+                const mat = cv.imread(detectionCanvas);
+                const contour = scanner.findPaperContour(mat);
+                mat.delete();
 
-              if (contour) {
-                corners = scannerRef.current.getCornerPoints(contour);
+                if (contour) {
+                  corners = scanner.getCornerPoints(contour);
+                }
               }
 
               const detectionTime = performance.now() - detectionStart;
@@ -660,7 +684,9 @@ export default function MobileScannerPage() {
       let finalDataUrl: string;
 
       // Apply jscanify processing if enabled and available
-      if (autoEnhance && scannerRef.current && openCvReady) {
+      const cv = window.cv;
+      const scanner = scannerRef.current;
+      if (autoEnhance && scanner && openCvReady && cv) {
         try {
           // Create low-res canvas for detection (faster processing)
           const detectionCanvas = document.createElement("canvas");
@@ -683,11 +709,11 @@ export default function MobileScannerPage() {
           );
 
           // Run detection on low-res image
-          const mat = (window as any).cv.imread(detectionCanvas);
-          const contour = scannerRef.current.findPaperContour(mat);
+          const mat = cv.imread(detectionCanvas);
+          const contour = scanner.findPaperContour(mat);
 
           if (contour) {
-            const cornerPoints = scannerRef.current.getCornerPoints(contour);
+            const cornerPoints = scanner.getCornerPoints(contour);
 
             // Scale corner points back to full resolution
             if (cornerPoints) {
@@ -746,7 +772,7 @@ export default function MobileScannerPage() {
               const docHeight = Math.round((leftHeight + rightHeight) / 2);
 
               // Extract paper from full-resolution canvas with scaled corner points
-              const resultCanvas = scannerRef.current.extractPaper(
+              const resultCanvas = scanner.extractPaper(
                 canvas,
                 docWidth,
                 docHeight,
@@ -891,8 +917,8 @@ export default function MobileScannerPage() {
     try {
       const videoTrack = streamRef.current.getVideoTracks()[0];
       await videoTrack.applyConstraints({
-        advanced: [{ torch: !torchEnabled } as any], // Cast to any for experimental torch API
-      } as any);
+        advanced: [{ torch: !torchEnabled }],
+      });
       setTorchEnabled(!torchEnabled);
       console.log("Torch:", !torchEnabled ? "ON" : "OFF");
     } catch (err) {
diff --git a/frontend/editor/src/core/tests/convert/ConvertIntegration.test.tsx b/frontend/editor/src/core/tests/convert/ConvertIntegration.test.tsx
index e0555d25f8..06f9198f05 100644
--- a/frontend/editor/src/core/tests/convert/ConvertIntegration.test.tsx
+++ b/frontend/editor/src/core/tests/convert/ConvertIntegration.test.tsx
@@ -123,7 +123,7 @@ describe("Convert Tool Integration Tests", () => {
   beforeEach(() => {
     vi.clearAllMocks();
     // Setup default apiClient mock
-    mockedApiClient.post = vi.fn() as any;
+    mockedApiClient.post = vi.fn() as typeof mockedApiClient.post;
   });
 
   afterEach(() => {
diff --git a/frontend/editor/src/core/tests/live/watched-folders.spec.ts b/frontend/editor/src/core/tests/live/watched-folders.spec.ts
index 8f6e09d4b6..6ee7dddd7c 100644
--- a/frontend/editor/src/core/tests/live/watched-folders.spec.ts
+++ b/frontend/editor/src/core/tests/live/watched-folders.spec.ts
@@ -83,7 +83,10 @@ async function getIDBFolders(
         const all = tx.objectStore(storeName).getAll();
         all.onsuccess = () =>
           resolve(
-            (all.result || []).map((f: any) => ({ id: f.id, name: f.name })),
+            (all.result || []).map((f: { id: string; name: string }) => ({
+              id: f.id,
+              name: f.name,
+            })),
           );
         all.onerror = () => resolve([]);
       };
@@ -275,7 +278,7 @@ test.describe("Watched Folders — Create / Edit / Delete", () => {
           dbName: string,
           storeName: string,
           key: string,
-          value: any,
+          value: unknown,
         ) =>
           new Promise<void>((resolve) => {
             const req = indexedDB.open(dbName);
diff --git a/frontend/editor/src/core/tools/AddAttachments.tsx b/frontend/editor/src/core/tools/AddAttachments.tsx
index 22c9713b68..17e5d7b0b1 100644
--- a/frontend/editor/src/core/tools/AddAttachments.tsx
+++ b/frontend/editor/src/core/tools/AddAttachments.tsx
@@ -1,7 +1,10 @@
 import { useEffect } from "react";
 import { useTranslation } from "react-i18next";
 import { useViewScopedFiles } from "@app/hooks/tools/shared/useViewScopedFiles";
-import { createToolFlow } from "@app/components/tools/shared/createToolFlow";
+import {
+  createToolFlow,
+  type MiddleStepConfig,
+} from "@app/components/tools/shared/createToolFlow";
 import { BaseToolProps, ToolComponent } from "@app/types/tool";
 import { useEndpointEnabled } from "@app/hooks/useEndpointConfig";
 import { useAddAttachmentsParameters } from "@app/hooks/tools/addAttachments/useAddAttachmentsParameters";
@@ -36,9 +39,9 @@ const AddAttachments = ({
       if (operation.files && onComplete) {
         onComplete(operation.files);
       }
-    } catch (error: any) {
+    } catch (error) {
       onError?.(
-        error?.message ||
+        (error instanceof Error ? error.message : undefined) ||
           t(
             "AddAttachmentsRequest.error.failed",
             "Add attachments operation failed",
@@ -70,7 +73,7 @@ const AddAttachments = ({
   });
 
   const getSteps = () => {
-    const steps: any[] = [];
+    const steps: MiddleStepConfig[] = [];
 
     // Step 1: Attachments Selection
     steps.push({
diff --git a/frontend/editor/src/core/tools/AddPageNumbers.tsx b/frontend/editor/src/core/tools/AddPageNumbers.tsx
index db6e5404e5..7001dc2894 100644
--- a/frontend/editor/src/core/tools/AddPageNumbers.tsx
+++ b/frontend/editor/src/core/tools/AddPageNumbers.tsx
@@ -1,7 +1,10 @@
 import { useEffect } from "react";
 import { useTranslation } from "react-i18next";
 import { useViewScopedFiles } from "@app/hooks/tools/shared/useViewScopedFiles";
-import { createToolFlow } from "@app/components/tools/shared/createToolFlow";
+import {
+  createToolFlow,
+  type MiddleStepConfig,
+} from "@app/components/tools/shared/createToolFlow";
 import { BaseToolProps, ToolComponent } from "@app/types/tool";
 import { useEndpointEnabled } from "@app/hooks/useEndpointConfig";
 import { useAddPageNumbersParameters } from "@app/components/tools/addPageNumbers/useAddPageNumbersParameters";
@@ -35,9 +38,9 @@ const AddPageNumbers = ({
       if (operation.files && onComplete) {
         onComplete(operation.files);
       }
-    } catch (error: any) {
+    } catch (error) {
       onError?.(
-        error?.message ||
+        (error instanceof Error ? error.message : undefined) ||
           t("addPageNumbers.error.failed", "Add page numbers operation failed"),
       );
     }
@@ -67,7 +70,7 @@ const AddPageNumbers = ({
   });
 
   const getSteps = () => {
-    const steps: any[] = [];
+    const steps: MiddleStepConfig[] = [];
 
     // Step 1: Position Selection & Pages/Starting Number
     steps.push({
diff --git a/frontend/editor/src/core/tools/AddStamp.tsx b/frontend/editor/src/core/tools/AddStamp.tsx
index b5c5d913fc..9a7422188e 100644
--- a/frontend/editor/src/core/tools/AddStamp.tsx
+++ b/frontend/editor/src/core/tools/AddStamp.tsx
@@ -1,6 +1,9 @@
 import { useEffect, useState } from "react";
 import { useTranslation } from "react-i18next";
-import { createToolFlow } from "@app/components/tools/shared/createToolFlow";
+import {
+  createToolFlow,
+  type MiddleStepConfig,
+} from "@app/components/tools/shared/createToolFlow";
 import { BaseToolProps, ToolComponent } from "@app/types/tool";
 import { useEndpointEnabled } from "@app/hooks/useEndpointConfig";
 import { useViewScopedFiles } from "@app/hooks/tools/shared/useViewScopedFiles";
@@ -41,9 +44,9 @@ const AddStamp = ({ onPreviewFile, onComplete, onError }: BaseToolProps) => {
       if (operation.files && onComplete) {
         onComplete(operation.files);
       }
-    } catch (error: any) {
+    } catch (error) {
       onError?.(
-        error?.message ||
+        (error instanceof Error ? error.message : undefined) ||
           t("AddStampRequest.error.failed", "Add stamp operation failed"),
       );
     }
@@ -73,7 +76,7 @@ const AddStamp = ({ onPreviewFile, onComplete, onError }: BaseToolProps) => {
   });
 
   const getSteps = () => {
-    const steps: any[] = [];
+    const steps: MiddleStepConfig[] = [];
 
     // Step 1: Stamp Setup
     steps.push({
diff --git a/frontend/editor/src/core/tools/EditTableOfContents.tsx b/frontend/editor/src/core/tools/EditTableOfContents.tsx
index 725c64124c..85769e0649 100644
--- a/frontend/editor/src/core/tools/EditTableOfContents.tsx
+++ b/frontend/editor/src/core/tools/EditTableOfContents.tsx
@@ -26,6 +26,7 @@ import {
   useNavigationState,
 } from "@app/contexts/NavigationContext";
 import { useFileSelection } from "@app/contexts/FileContext";
+import { isStirlingFile } from "@app/types/fileContext";
 
 const extractBookmarks = async (file: File): Promise<BookmarkPayload[]> => {
   const formData = new FormData();
@@ -39,7 +40,7 @@ const extractBookmarks = async (file: File): Promise<BookmarkPayload[]> => {
   return response.data as BookmarkPayload[];
 };
 
-const useStableCallback = <T extends (...args: any[]) => any>(
+const useStableCallback = <T extends (...args: never[]) => unknown>(
   callback: T,
 ): T => {
   const callbackRef = useRef(callback);
@@ -112,7 +113,7 @@ const EditTableOfContents = (props: BaseToolProps) => {
         const payload = await extractBookmarks(file);
         const bookmarks = hydrateBookmarkPayload(payload);
         setBookmarks(bookmarks);
-        setLastLoadedFileId((file as any)?.fileId ?? file.name);
+        setLastLoadedFileId(isStirlingFile(file) ? file.fileId : file.name);
 
         if (showToast) {
           alert({
@@ -164,7 +165,7 @@ const EditTableOfContents = (props: BaseToolProps) => {
       return;
     }
 
-    const fileId = (selectedFile as any)?.fileId ?? selectedFile.name;
+    const fileId = selectedFile.fileId;
     if (fileId === lastLoadedFileId) {
       return;
     }
@@ -466,6 +467,7 @@ const EditTableOfContents = (props: BaseToolProps) => {
   });
 };
 
-(EditTableOfContents as any).tool = () => useEditTableOfContentsOperation;
+(EditTableOfContents as ToolComponent).tool = () =>
+  useEditTableOfContentsOperation;
 
 export default EditTableOfContents as ToolComponent;
diff --git a/frontend/editor/src/core/tools/ReorganizePages.tsx b/frontend/editor/src/core/tools/ReorganizePages.tsx
index dcf5c1ae9c..024469bee4 100644
--- a/frontend/editor/src/core/tools/ReorganizePages.tsx
+++ b/frontend/editor/src/core/tools/ReorganizePages.tsx
@@ -34,9 +34,9 @@ const ReorganizePages = ({
       if (operation.files && onComplete) {
         onComplete(operation.files);
       }
-    } catch (error: any) {
+    } catch (error) {
       onError?.(
-        error?.message ||
+        (error instanceof Error ? error.message : undefined) ||
           t("reorganizePages.error.failed", "Failed to reorganize pages"),
       );
     }
@@ -107,6 +107,6 @@ const ReorganizePages = ({
   });
 };
 
-(ReorganizePages as any).tool = () => useReorganizePagesOperation;
+(ReorganizePages as ToolComponent).tool = () => useReorganizePagesOperation;
 
 export default ReorganizePages as ToolComponent;
diff --git a/frontend/editor/src/core/tools/formFill/FormFill.tsx b/frontend/editor/src/core/tools/formFill/FormFill.tsx
index 846c1dcc83..0e4829df69 100644
--- a/frontend/editor/src/core/tools/formFill/FormFill.tsx
+++ b/frontend/editor/src/core/tools/formFill/FormFill.tsx
@@ -28,6 +28,7 @@ import {
   ActionIcon,
 } from "@mantine/core";
 import { useTranslation } from "react-i18next";
+import { isAxiosError } from "axios";
 import {
   useFormFill,
   useAllFormValues,
@@ -267,13 +268,15 @@ const FormFill = (_props: BaseToolProps) => {
         detail: { blob: filledBlob },
       });
       window.dispatchEvent(event);
-    } catch (err: any) {
+    } catch (err) {
+      const status = isAxiosError(err) ? err.response?.status : undefined;
       const message =
-        err?.response?.status === 413
+        status === 413
           ? "File too large. Try reducing the PDF size first."
-          : err?.response?.status === 400
+          : status === 400
             ? "Invalid form data. Please check all fields."
-            : err?.message || "Failed to save filled form";
+            : (err instanceof Error ? err.message : undefined) ||
+              "Failed to save filled form";
       setSaveError(message);
       console.error("[FormFill] Save failed:", err);
     } finally {
diff --git a/frontend/editor/src/core/tools/formFill/FormFillContext.tsx b/frontend/editor/src/core/tools/formFill/FormFillContext.tsx
index 217b568bbc..4377984111 100644
--- a/frontend/editor/src/core/tools/formFill/FormFillContext.tsx
+++ b/frontend/editor/src/core/tools/formFill/FormFillContext.tsx
@@ -30,6 +30,7 @@ import React, {
   useSyncExternalStore,
 } from "react";
 import { useDebouncedCallback } from "@mantine/hooks";
+import { isAxiosError } from "axios";
 import type {
   FormField,
   FormFillState,
@@ -361,11 +362,13 @@ export function FormFillProvider({
         forFileIdRef.current = fileId ?? null;
         setForFileId(fileId ?? null);
         dispatch({ type: "FETCH_SUCCESS", fields });
-      } catch (err: any) {
+      } catch (err) {
         if (fetchVersionRef.current !== version) return; // stale
         const msg =
-          err?.response?.data?.message ||
-          err?.message ||
+          (isAxiosError<{ message?: string }>(err)
+            ? err.response?.data?.message
+            : undefined) ||
+          (err instanceof Error ? err.message : undefined) ||
           "Failed to fetch form fields";
         dispatch({ type: "FETCH_ERROR", error: msg });
       }
diff --git a/frontend/editor/src/core/tools/pdfTextEditor/PdfTextEditor.tsx b/frontend/editor/src/core/tools/pdfTextEditor/PdfTextEditor.tsx
index bf9628f5b3..fee07ac6ea 100644
--- a/frontend/editor/src/core/tools/pdfTextEditor/PdfTextEditor.tsx
+++ b/frontend/editor/src/core/tools/pdfTextEditor/PdfTextEditor.tsx
@@ -1,5 +1,6 @@
 import { useCallback, useEffect, useMemo, useState, useRef } from "react";
 import { useTranslation } from "react-i18next";
+import { isAxiosError } from "axios";
 import DescriptionIcon from "@mui/icons-material/DescriptionOutlined";
 
 import { useToolWorkflow } from "@app/contexts/ToolWorkflowContext";
@@ -16,6 +17,7 @@ import {
 import { useViewer } from "@app/contexts/ViewerContext";
 import { createStirlingFilesAndStubs } from "@app/services/fileStubHelpers";
 import { BaseToolProps, ToolComponent } from "@app/types/tool";
+import type { FileId } from "@app/types/file";
 import { getDefaultWorkbench } from "@app/types/workbench";
 import { CONVERSION_ENDPOINTS } from "@app/constants/convertConstants";
 import apiClient from "@app/services/apiClient";
@@ -294,7 +296,7 @@ const PdfTextEditor = ({ onComplete, onError }: BaseToolProps) => {
   const imagesByPageRef = useRef<PdfJsonImageElement[][]>([]);
   const lastLoadedFileRef = useRef<File | null>(null);
   const autoLoadKeyRef = useRef<string | null>(null);
-  const sourceFileIdRef = useRef<string | null>(null);
+  const sourceFileIdRef = useRef<FileId | null>(null);
   const loadRequestIdRef = useRef(0);
   const latestPdfRequestIdRef = useRef<number | null>(null);
   const loadedDocumentRef = useRef<PdfJsonDocument | null>(null);
@@ -339,8 +341,8 @@ const PdfTextEditor = ({ onComplete, onError }: BaseToolProps) => {
     };
   }, []);
 
-  const isCacheUnavailableError = useCallback((error: any): boolean => {
-    const status = error?.response?.status;
+  const isCacheUnavailableError = useCallback((error: unknown): boolean => {
+    const status = isAxiosError(error) ? error.response?.status : undefined;
     // Treat any 410 as cache unavailable, since responseType: 'blob' makes
     // it impossible to reliably check the JSON body
     return status === 410;
@@ -804,14 +806,20 @@ const PdfTextEditor = ({ onComplete, onError }: BaseToolProps) => {
               } else {
                 console.log("Job not complete yet, continuing to poll...");
               }
-            } catch (pollError: any) {
+            } catch (pollError) {
               console.error("Error polling job status:", pollError);
+              const status = isAxiosError(pollError)
+                ? pollError.response?.status
+                : undefined;
               console.error("Poll error details:", {
-                status: pollError?.response?.status,
-                data: pollError?.response?.data,
-                message: pollError?.message,
+                status,
+                data: isAxiosError(pollError)
+                  ? pollError.response?.data
+                  : undefined,
+                message:
+                  pollError instanceof Error ? pollError.message : undefined,
               });
-              if (pollError?.response?.status === 404) {
+              if (status === 404) {
                 throw new Error("Job not found on server", {
                   cause: pollError,
                 });
@@ -864,12 +872,12 @@ const PdfTextEditor = ({ onComplete, onError }: BaseToolProps) => {
         cachedJobIdRef.current = newJobId;
         setFileName(file.name);
         setErrorMessage(null);
-      } catch (error: any) {
+      } catch (error) {
         console.error("Failed to load file", error);
         console.error("Error details:", {
-          message: error?.message,
-          response: error?.response?.data,
-          stack: error?.stack,
+          message: error instanceof Error ? error.message : undefined,
+          response: isAxiosError(error) ? error.response?.data : undefined,
+          stack: error instanceof Error ? error.stack : undefined,
         });
 
         if (loadRequestIdRef.current !== requestId) {
@@ -885,7 +893,7 @@ const PdfTextEditor = ({ onComplete, onError }: BaseToolProps) => {
 
         if (isPdf) {
           const errorMsg =
-            error?.message ||
+            (error instanceof Error ? error.message : undefined) ||
             t(
               "pdfTextEditor.conversionFailed",
               "Failed to convert PDF. Please try again.",
@@ -1406,11 +1414,11 @@ const PdfTextEditor = ({ onComplete, onError }: BaseToolProps) => {
           onComplete([pdfFile]);
         }
         setErrorMessage(null);
-      } catch (error: any) {
+      } catch (error) {
         console.error("Failed to convert JSON back to PDF", error);
         const message =
-          error?.response?.data ||
-          error?.message ||
+          (isAxiosError(error) ? error.response?.data : undefined) ||
+          (error instanceof Error ? error.message : undefined) ||
           t(
             "pdfTextEditor.errors.pdfConversion",
             "Unable to convert the edited JSON back into a PDF.",
@@ -1451,9 +1459,8 @@ const PdfTextEditor = ({ onComplete, onError }: BaseToolProps) => {
         return;
       }
 
-      const parentStub = selectors.getStirlingFileStub(
-        sourceFileIdRef.current as any,
-      );
+      const sourceFileId = sourceFileIdRef.current;
+      const parentStub = selectors.getStirlingFileStub(sourceFileId);
       if (!parentStub) {
         console.warn(
           "[PdfTextEditor] Could not find parent stub for save to workbench",
@@ -1660,11 +1667,7 @@ const PdfTextEditor = ({ onComplete, onError }: BaseToolProps) => {
       );
 
       // Replace the original file with the edited version
-      await consumeFiles(
-        [sourceFileIdRef.current as any],
-        stirlingFiles,
-        stubs,
-      );
+      await consumeFiles([sourceFileId], stirlingFiles, stubs);
 
       // Update the source file ID to point to the new file
       sourceFileIdRef.current = stubs[0].id;
@@ -1676,11 +1679,11 @@ const PdfTextEditor = ({ onComplete, onError }: BaseToolProps) => {
 
       // Set flag to trigger navigation after state update is processed
       setShouldNavigateAfterSave(true);
-    } catch (error: any) {
+    } catch (error) {
       console.error("Failed to save to workbench", error);
       const message =
-        error?.response?.data ||
-        error?.message ||
+        (isAxiosError(error) ? error.response?.data : undefined) ||
+        (error instanceof Error ? error.message : undefined) ||
         t(
           "pdfTextEditor.errors.pdfConversion",
           "Unable to save changes to workbench.",
@@ -1955,7 +1958,7 @@ const PdfTextEditor = ({ onComplete, onError }: BaseToolProps) => {
 
     autoLoadKeyRef.current = fileKey;
     // Capture the source file ID for save-to-workbench functionality
-    sourceFileIdRef.current = (autoLoadFile as any).fileId ?? null;
+    sourceFileIdRef.current = autoLoadFile.fileId ?? null;
     void handleLoadFile(autoLoadFile);
   }, [autoLoadFile, navigationState.selectedTool, handleLoadFile]);
 
diff --git a/frontend/editor/src/core/utils/loadJscanify.ts b/frontend/editor/src/core/utils/loadJscanify.ts
index 93dec00394..94b141bba2 100644
--- a/frontend/editor/src/core/utils/loadJscanify.ts
+++ b/frontend/editor/src/core/utils/loadJscanify.ts
@@ -1,9 +1,52 @@
 import { withBasePath } from "@app/constants/app";
 
+/** A single point in image space, as returned by jscanify corner detection. */
+export interface JscanifyPoint {
+  x: number;
+  y: number;
+}
+
+/** The four detected document corners returned by {@link JscanifyScanner.getCornerPoints}. */
+export interface JscanifyCornerPoints {
+  topLeftCorner: JscanifyPoint;
+  topRightCorner: JscanifyPoint;
+  bottomLeftCorner: JscanifyPoint;
+  bottomRightCorner: JscanifyPoint;
+}
+
+/** Minimal subset of an OpenCV.js `Mat` that this app interacts with directly. */
+export interface OpenCVMat {
+  delete(): void;
+}
+
+/** Minimal subset of the OpenCV.js runtime exposed on `window.cv`. */
+export interface OpenCV {
+  /** Defined only once the WASM runtime has finished initializing. */
+  readonly Mat: unknown;
+  imread(source: HTMLImageElement | HTMLCanvasElement | string): OpenCVMat;
+}
+
+/** The jscanify scanner instance API used by the mobile scanner. */
+export interface JscanifyScanner {
+  findPaperContour(image: OpenCVMat): OpenCVMat | undefined;
+  getCornerPoints(contour: OpenCVMat): JscanifyCornerPoints;
+  extractPaper(
+    image: HTMLCanvasElement,
+    resultWidth: number,
+    resultHeight: number,
+    cornerPoints?: JscanifyCornerPoints,
+  ): HTMLCanvasElement;
+}
+
+/** Constructor for jscanify, exposed on `window.jscanify`. */
+export interface JscanifyConstructor {
+  new (): JscanifyScanner;
+}
+
 declare global {
   interface Window {
-    cv?: any;
-    jscanify?: any;
+    cv?: OpenCV;
+    jscanify?: JscanifyConstructor;
   }
 }
 
diff --git a/frontend/eslint.config.mjs b/frontend/eslint.config.mjs
index 55950ad1b7..a176ef8541 100644
--- a/frontend/eslint.config.mjs
+++ b/frontend/eslint.config.mjs
@@ -215,10 +215,9 @@ export default defineConfig(
       "editor/src/core/contexts/**/*.{js,mjs,jsx,ts,tsx}",
       "editor/src/core/data/**/*.{js,mjs,jsx,ts,tsx}",
       "editor/src/core/hooks/**/*.{js,mjs,jsx,ts,tsx}",
-      "editor/src/core/pages/**/*.{js,mjs,jsx,ts,tsx}",
       "editor/src/core/services/**/*.{js,mjs,jsx,ts,tsx}",
-      "editor/src/core/tests/**/*.{js,mjs,jsx,ts,tsx}",
-      "editor/src/core/tools/**/*.{js,mjs,jsx,ts,tsx}",
+      "editor/src/core/tools/Automate.tsx",
+      "editor/src/core/tools/annotate/useAnnotationSelection.ts",
       "editor/src/core/types/**/*.{js,mjs,jsx,ts,tsx}",
       "editor/src/core/utils/**/*.{js,mjs,jsx,ts,tsx}",
     ],