diff --git a/packages/office-render/src/presentation/cursor-canvas-runtime.tsx b/packages/office-render/src/presentation/cursor-canvas-runtime.tsx
index f65b6bdb4..ecf49826b 100644
--- a/packages/office-render/src/presentation/cursor-canvas-runtime.tsx
+++ b/packages/office-render/src/presentation/cursor-canvas-runtime.tsx
@@ -64,7 +64,10 @@ export function PresentationCursorCanvas({
     0,
     slides.findIndex((slide) => asNumber(slide.index, 1) === selectedIndex),
   );
-  const selectedSlide = slides[selectedPosition] ?? slides[0] ?? {};
+  const selectedSlide = useMemo(
+    () => slides[selectedPosition] ?? slides[0] ?? {},
+    [slides, selectedPosition],
+  );
   const selectedSlideIndex = asNumber(selectedSlide.index, selectedPosition + 1);
   const title = asString(artifact.title) || "Presentation";
 
@@ -77,7 +80,11 @@ export function PresentationCursorCanvas({
     if (slides.some((slide) => asNumber(slide.index, 1) === selectedIndex)) {
       return;
     }
-    setSelectedIndex(asNumber(slides[0]?.index, 1));
+    const firstIndex = asNumber(slides[0]?.index, 1);
+    if (firstIndex !== selectedIndex) {
+      // eslint-disable-next-line react-hooks/set-state-in-effect -- sync when slide set changes and current index is stale
+      setSelectedIndex(firstIndex);
+    }
   }, [selectedIndex, slides]);
 
   const goPrevious = useCallback(() => {
@@ -151,6 +158,7 @@ export function PresentationCursorCanvas({
               >
                 <span style={styles.thumbnailNumber}>{slideIndex}</span>
                 {thumbnail ? (
+                  // eslint-disable-next-line @next/next/no-img-element -- office thumbnail, not a Next.js route image
                   <img
                     alt=""
                     src={thumbnail}
@@ -430,7 +438,8 @@ function useLoadedCanvasImages(
     const next = new Map<string, CanvasImageSource>();
     const entries = Object.entries(media);
     if (entries.length === 0) {
-      setImages(next);
+      // eslint-disable-next-line react-hooks/set-state-in-effect -- sync when media set is empty
+      if (!cancelled) setImages(next);
       return;
     }
 
diff --git a/packages/office-render/src/presentation/presentation-preview.tsx b/packages/office-render/src/presentation/presentation-preview.tsx
index 6bbe8304d..82d631fbb 100644
--- a/packages/office-render/src/presentation/presentation-preview.tsx
+++ b/packages/office-render/src/presentation/presentation-preview.tsx
@@ -385,7 +385,7 @@ function SlideshowOverlay({
   const frameSize = useElementSize(frameRef);
   const didEnterFullscreenRef = useRef(typeof document !== "undefined" && document.fullscreenElement != null);
   const selectedIndex = Math.min(activeSlideIndex, Math.max(0, slides.length - 1));
-  const slide = slides[selectedIndex] ?? {};
+  const slide = useMemo(() => slides[selectedIndex] ?? {}, [slides, selectedIndex]);
   const frame = getSlideFrameSize(slide, layouts);
   const fit = computePresentationFit(frameSize, frame, { padding: 0 });
   const canvasWidth = Math.max(1, fit.width);
@@ -396,11 +396,8 @@ function SlideshowOverlay({
   const showSpeakerNotesLabel = labels.showSpeakerNotes ?? speakerNotesLabel;
   const hideSpeakerNotesLabel = labels.hideSpeakerNotes ?? speakerNotesLabel;
 
-  useEffect(() => {
-    if (!hasSpeakerNotes) {
-      setShowSpeakerNotes(false);
-    }
-  }, [hasSpeakerNotes]);
+  // When there are no speaker notes, the panel cannot be shown.
+  const canShowSpeakerNotes = hasSpeakerNotes && showSpeakerNotes;
 
   const goPrevious = useCallback(() => {
     setActiveSlideIndex(Math.max(0, selectedIndex - 1));
@@ -508,7 +505,7 @@ function SlideshowOverlay({
         {hasSpeakerNotes ? (
           <button
             aria-label={showSpeakerNotes ? hideSpeakerNotesLabel : showSpeakerNotesLabel}
-            aria-pressed={showSpeakerNotes}
+            aria-pressed={canShowSpeakerNotes}
             className={styles.slideshowIconButton}
             data-testid="presentation-speaker-notes-toggle"
             onClick={() => setShowSpeakerNotes((isOpen) => !isOpen)}
@@ -521,7 +518,7 @@ function SlideshowOverlay({
           <PresentationIcon name="close" />
         </button>
       </div>
-      <div className={styles.slideshowPresenterLayout} data-notes-open={showSpeakerNotes && hasSpeakerNotes}>
+      <div className={styles.slideshowPresenterLayout} data-notes-open={canShowSpeakerNotes}>
         <button
           aria-label={labels.nextSlide}
           className={styles.slideshowFrame}
@@ -540,7 +537,7 @@ function SlideshowOverlay({
             width={canvasWidth}
           />
         </button>
-        {showSpeakerNotes && hasSpeakerNotes ? (
+        {canShowSpeakerNotes ? (
           <aside className={styles.slideshowNotesPanel} data-testid="presentation-speaker-notes">
             <div className={styles.slideshowNotesTitle}>{speakerNotesLabel}</div>
             <pre className={styles.slideshowNotesText}>{speakerNotes}</pre>
diff --git a/packages/office-render/src/shared/office-color-utils.ts b/packages/office-render/src/shared/office-color-utils.ts
index 5367e70b1..613c9e57d 100644
--- a/packages/office-render/src/shared/office-color-utils.ts
+++ b/packages/office-render/src/shared/office-color-utils.ts
@@ -93,15 +93,11 @@ function modulateSaturation(
   const saturation = lightness > 0.5
     ? delta / (2 - max - min)
     : delta / (max + min);
-  let hue = 0;
-  if (max === channels[0]) {
-    hue = (channels[1]! - channels[2]!) / delta + (channels[1]! < channels[2]! ? 6 : 0);
-  } else if (max === channels[1]) {
-    hue = (channels[2]! - channels[0]!) / delta + 2;
-  } else {
-    hue = (channels[0]! - channels[1]!) / delta + 4;
-  }
-  hue /= 6;
+  const hue = (max === channels[0]
+    ? (channels[1]! - channels[2]!) / delta + (channels[1]! < channels[2]! ? 6 : 0)
+    : max === channels[1]
+      ? (channels[2]! - channels[0]!) / delta + 2
+      : (channels[0]! - channels[1]!) / delta + 4) / 6;
 
   return hslToRgb(hue, Math.max(0, Math.min(1, saturation * factor)), lightness);
 }
diff --git a/packages/office/src/cursor-canvas.ts b/packages/office/src/cursor-canvas.ts
index 982f85323..3d920a559 100644
--- a/packages/office/src/cursor-canvas.ts
+++ b/packages/office/src/cursor-canvas.ts
@@ -1322,6 +1322,7 @@ function officeRenderPresentationRuntimeInline(): string {
       `Missing @autodev/office-render Cursor runtime at ${runtimePath}. ` +
         "Run `npm --prefix packages/office-render run build` before generating a PPTX Cursor Canvas. " +
         message,
+      { cause: error },
     );
   }
 }
diff --git a/scripts/docs/feature-tree-generator.ts b/scripts/docs/feature-tree-generator.ts
index 60bcb7ebc..e815ef863 100644
--- a/scripts/docs/feature-tree-generator.ts
+++ b/scripts/docs/feature-tree-generator.ts
@@ -42,7 +42,7 @@ const {
 } = resolveFeatureTreeGeneratorRuntime(featureTreeGeneratorModule as FeatureTreeGeneratorModuleShape);
 const { INFERRED_GROUP_ID, buildApiLookupKey, normalizeSurfaceMetadata } = featureSurfaceMetadata;
 
-type GenerateFeatureTreeArtifacts = (options: {
+type _GenerateFeatureTreeArtifacts = (options: {
   repoRoot: string;
   scanRoot?: string;
   metadata?: FeatureMetadata | null;
@@ -56,7 +56,7 @@ type GenerateFeatureTreeArtifacts = (options: {
   apisCount: number;
 }>;
 
-type FeatureTreePreflightResult = {
+type _FeatureTreePreflightResult = {
   repoRoot: string;
   selectedScanRoot: string;
   frameworksDetected: string[];
@@ -1298,7 +1298,7 @@ export async function main(argv: string[] = process.argv.slice(2)): Promise<void
   const metadata = loadPersistedFeatureMetadata(existingFeatureTree, existingSurfaceIndex);
   const apiFeatures = extractApiFeatures(apiContract);
   const tree = buildFeatureTree(routes, apiFeatures);
-  const surfaceIndex = buildFeatureSurfaceIndex(routes, apiFeatures, nextjsApis, rustApis, metadata);
+  void buildFeatureSurfaceIndex(routes, apiFeatures, nextjsApis, rustApis, metadata);
 
   if (args.has("--mermaid")) {
     console.log(renderMermaid(tree));
diff --git a/scripts/docs/framework-feature-tree-generator.ts b/scripts/docs/framework-feature-tree-generator.ts
index 639009108..0df262de5 100644
--- a/scripts/docs/framework-feature-tree-generator.ts
+++ b/scripts/docs/framework-feature-tree-generator.ts
@@ -771,7 +771,7 @@ function extractSpringControllerRoutes(repoRoot: string): SpringControllerRoute[
     const classBasePath = classMappings[0]?.path ?? "";
 
     const methodRegex =
-      /((?:@\w+(?:\((?:[^()]|\([^()]*\))*\))?\s*)+)\s*public\s+[A-Za-z0-9_<>,?.\[\]\s]+\s+(\w+)\s*\((?:[^()]|\([^()]*\))*\)\s*(?:throws\s+[A-Za-z0-9_<>,?.\[\]\s]+)?\s*\{/gs;
+      /((?:@\w+(?:\((?:[^()]|\([^()]*\))*\))?\s*)+)\s*public\s+[A-Za-z0-9_<>,?.[\]\s]+\s+(\w+)\s*\((?:[^()]|\([^()]*\))*\)\s*(?:throws\s+[A-Za-z0-9_<>,?.[\]\s]+)?\s*\{/gs;
     let match: RegExpExecArray | null;
 
     while ((match = methodRegex.exec(content)) !== null) {
diff --git a/scripts/harness/analyze-search-tool-usage.ts b/scripts/harness/analyze-search-tool-usage.ts
index 8f37d8a76..fe41e502b 100644
--- a/scripts/harness/analyze-search-tool-usage.ts
+++ b/scripts/harness/analyze-search-tool-usage.ts
@@ -70,7 +70,7 @@ const FAMILY_KEYS: SearchToolFamily[] = [
   "custom_glob",
 ];
 
-const PATTERN_CATEGORY_KEYS: SearchPatternCategory[] = [
+const _PATTERN_CATEGORY_KEYS: SearchPatternCategory[] = [
   "path_like",
   "symbol_like",
   "natural_language",
@@ -654,7 +654,7 @@ function collectJsonlFiles(rootPath: string, maxFiles?: number): string[] {
       continue;
     }
 
-    let entries: fs.Dirent[] = [];
+    let entries: fs.Dirent[];
     try {
       entries = fs.readdirSync(current, { withFileTypes: true });
     } catch {
diff --git a/scripts/mcp-http-proxy.mjs b/scripts/mcp-http-proxy.mjs
index ae26dcd51..8d35fd6d5 100644
--- a/scripts/mcp-http-proxy.mjs
+++ b/scripts/mcp-http-proxy.mjs
@@ -76,7 +76,7 @@ proxy.setRequestHandler(GetPromptRequestSchema, async (request) => {
 });
 
 let upstreamTransport;
-let stdioTransport;
+let stdioTransport; // eslint-disable-line prefer-const -- may be undefined until connect()
 let shuttingDown = false;
 
 async function shutdown(reason) {
@@ -101,7 +101,7 @@ function formatError(err) {
 
 // Connect to upstream first, then start stdio server
 try {
-  upstreamTransport = new StreamableHTTPClientTransport(new URL(normalizedEndpoint), {
+  upstreamTransport = new StreamableHTTPClientTransport(new globalThis.URL(normalizedEndpoint), {
     requestInit: headers ? { headers } : undefined,
   });
   await upstreamClient.connect(upstreamTransport);
diff --git a/tools/hook-runtime/src/specialist-review.ts b/tools/hook-runtime/src/specialist-review.ts
index 94ddceafb..fb4e10024 100644
--- a/tools/hook-runtime/src/specialist-review.ts
+++ b/tools/hook-runtime/src/specialist-review.ts
@@ -429,7 +429,7 @@ async function callReviewProvider(params: {
         provider: fallbackProvider,
       });
       if (validate && !validate(raw)) {
-        throw new Error(`Automatic review specialist returned an invalid verdict: ${raw || "(empty response)"}`);
+        throw new Error(`Automatic review specialist returned an invalid verdict: ${raw || "(empty response)"}`, { cause: primaryError });
       }
       return raw;
     } catch (fallbackError) {