diff --git a/apps/code/src/renderer/features/code-review/components/CloudReviewPage.tsx b/apps/code/src/renderer/features/code-review/components/CloudReviewPage.tsx
index 9c1c88f64..8cae2449e 100644
--- a/apps/code/src/renderer/features/code-review/components/CloudReviewPage.tsx
+++ b/apps/code/src/renderer/features/code-review/components/CloudReviewPage.tsx
@@ -4,12 +4,13 @@ import {
   extractCloudFileDiff,
   type ParsedToolCall,
 } from "@features/task-detail/utils/cloudToolChanges";
-import type { FileDiffOptions } from "@pierre/diffs";
-import { MultiFileDiff } from "@pierre/diffs/react";
 import { Flex, Spinner, Text } from "@radix-ui/themes";
 import type { ChangedFile, Task } from "@shared/types";
 import type { AcpMessage } from "@shared/types/session-events";
 import { useMemo } from "react";
+import { useReviewComment } from "../hooks/useReviewComment";
+import type { DiffOptions, OnCommentCallback } from "../types";
+import { InteractiveFileDiff } from "./InteractiveFileDiff";
 import {
   DeferredDiffPlaceholder,
   DiffFileHeader,
@@ -33,6 +34,7 @@ export function CloudReviewPage({ taskId, task }: CloudReviewPageProps) {
     changedFiles,
     isLoading,
   } = useCloudChangedFiles(taskId, task);
+  const onComment = useReviewComment(taskId);
   const events = session?.events ?? EMPTY_EVENTS;
   const summary = useMemo(() => buildCloudEventSummary(events), [events]);
 
@@ -117,6 +119,7 @@ export function CloudReviewPage({ taskId, task }: CloudReviewPageProps) {
               options={diffOptions}
               collapsed={isCollapsed}
               onToggle={() => toggleFile(file.path)}
+              onComment={onComment}
             />
           </div>
         );
@@ -131,12 +134,14 @@ function CloudFileDiff({
   options,
   collapsed,
   onToggle,
+  onComment,
 }: {
   file: ChangedFile;
   toolCalls: Map<string, ParsedToolCall>;
-  options: FileDiffOptions<unknown>;
+  options: DiffOptions;
   collapsed: boolean;
   onToggle: () => void;
+  onComment: OnCommentCallback;
 }) {
   const diff = useMemo(
     () => extractCloudFileDiff(toolCalls, file.path),
@@ -154,10 +159,11 @@ function CloudFileDiff({
   );
 
   return (
-    <MultiFileDiff
+    <InteractiveFileDiff
       oldFile={oldFile}
       newFile={newFile}
       options={{ ...options, collapsed }}
+      onComment={onComment}
       renderCustomHeader={(fd) => (
         <DiffFileHeader
           fileDiff={fd}
diff --git a/apps/code/src/renderer/features/code-review/components/CommentAnnotation.tsx b/apps/code/src/renderer/features/code-review/components/CommentAnnotation.tsx
new file mode 100644
index 000000000..613bc2778
--- /dev/null
+++ b/apps/code/src/renderer/features/code-review/components/CommentAnnotation.tsx
@@ -0,0 +1,74 @@
+import { useCallback, useRef } from "react";
+
+interface CommentAnnotationProps {
+  onSubmit: (text: string) => void;
+  onCancel: () => void;
+}
+
+export function CommentAnnotation({
+  onSubmit,
+  onCancel,
+}: CommentAnnotationProps) {
+  const textareaRef = useRef<HTMLTextAreaElement>(null);
+
+  const setTextareaRef = useCallback((el: HTMLTextAreaElement | null) => {
+    (
+      textareaRef as React.MutableRefObject<HTMLTextAreaElement | null>
+    ).current = el;
+    if (el) {
+      requestAnimationFrame(() => el.focus());
+    }
+  }, []);
+
+  const handleSubmit = useCallback(() => {
+    const text = textareaRef.current?.value?.trim();
+    if (text) {
+      onSubmit(text);
+    }
+  }, [onSubmit]);
+
+  const handleKeyDown = useCallback(
+    (e: React.KeyboardEvent) => {
+      if (e.key === "Enter" && (e.metaKey || e.ctrlKey)) {
+        e.preventDefault();
+        handleSubmit();
+      }
+      if (e.key === "Escape") {
+        e.preventDefault();
+        onCancel();
+      }
+    },
+    [handleSubmit, onCancel],
+  );
+
+  return (
+    <div
+      data-comment-annotation=""
+      className="whitespace-normal rounded-md border border-[var(--gray-5)] bg-[var(--gray-2)] px-2 py-2.5"
+    >
+      <textarea
+        ref={setTextareaRef}
+        placeholder="Describe the changes you'd like..."
+        onKeyDown={handleKeyDown}
+        className="w-full resize-none rounded border border-[var(--gray-6)] bg-[var(--color-background)] p-1.5 font-inherit text-[13px] text-[var(--gray-12)] leading-normal outline-none"
+        style={{ minHeight: 48 }}
+      />
+      <div className="mt-1.5 flex items-center gap-1.5">
+        <button
+          type="button"
+          onClick={handleSubmit}
+          className="cursor-pointer rounded border-none bg-[var(--accent-9)] px-2.5 py-0.5 font-medium text-[var(--gray-1)] text-xs leading-[18px]"
+        >
+          Send to agent
+        </button>
+        <button
+          type="button"
+          onClick={onCancel}
+          className="cursor-pointer border-none bg-transparent px-2 py-0.5 text-[var(--gray-9)] text-xs leading-[18px]"
+        >
+          Cancel
+        </button>
+      </div>
+    </div>
+  );
+}
diff --git a/apps/code/src/renderer/features/code-review/components/InteractiveFileDiff.tsx b/apps/code/src/renderer/features/code-review/components/InteractiveFileDiff.tsx
new file mode 100644
index 000000000..63fa8622b
--- /dev/null
+++ b/apps/code/src/renderer/features/code-review/components/InteractiveFileDiff.tsx
@@ -0,0 +1,275 @@
+import { ArrowCounterClockwise } from "@phosphor-icons/react";
+import {
+  type DiffLineAnnotation,
+  diffAcceptRejectHunk,
+  parseDiffFromFile,
+} from "@pierre/diffs";
+import { FileDiff, MultiFileDiff } from "@pierre/diffs/react";
+import { trpcClient, useTRPC } from "@renderer/trpc/client";
+import { useQueryClient } from "@tanstack/react-query";
+import { useCallback, useMemo, useRef, useState } from "react";
+import { useCommentState } from "../hooks/useCommentState";
+import type {
+  AnnotationMetadata,
+  FilesDiffProps,
+  InteractiveFileDiffProps,
+  PatchDiffProps,
+} from "../types";
+import {
+  buildCommentMergedOptions,
+  buildHunkAnnotations,
+} from "../utils/diffAnnotations";
+import { CommentAnnotation } from "./CommentAnnotation";
+
+function isPatchDiff(props: InteractiveFileDiffProps): props is PatchDiffProps {
+  return "fileDiff" in props && props.fileDiff != null;
+}
+
+export function InteractiveFileDiff(props: InteractiveFileDiffProps) {
+  if (isPatchDiff(props)) {
+    return <PatchDiffView {...props} />;
+  }
+  return <FilesDiffView {...props} />;
+}
+
+function PatchDiffView({
+  fileDiff: initialFileDiff,
+  repoPath,
+  options,
+  renderCustomHeader,
+  onComment,
+}: PatchDiffProps) {
+  const trpc = useTRPC();
+  const queryClient = useQueryClient();
+  const [fileDiff, setFileDiff] = useState(initialFileDiff);
+  const [revertingHunks, setRevertingHunks] = useState<Set<number>>(
+    () => new Set(),
+  );
+
+  const {
+    selectedRange,
+    commentAnnotation,
+    hasOpenComment,
+    reset,
+    handleLineSelectionEnd,
+  } = useCommentState();
+
+  const [lastInitial, setLastInitial] = useState(initialFileDiff);
+  if (initialFileDiff !== lastInitial) {
+    setLastInitial(initialFileDiff);
+    setFileDiff(initialFileDiff);
+    setRevertingHunks(new Set());
+    reset();
+  }
+
+  const currentFilePath = fileDiff.name ?? fileDiff.prevName ?? "";
+  const filePathRef = useRef(currentFilePath);
+  filePathRef.current = currentFilePath;
+
+  const hunkAnnotations = useMemo(
+    () => buildHunkAnnotations(fileDiff),
+    [fileDiff],
+  );
+  const annotations = useMemo(
+    () =>
+      commentAnnotation
+        ? [...hunkAnnotations, commentAnnotation]
+        : hunkAnnotations,
+    [hunkAnnotations, commentAnnotation],
+  );
+
+  const handleCommentSubmit = useCallback(
+    (text: string) => {
+      const meta = commentAnnotation?.metadata;
+      if (!currentFilePath || !meta || meta.kind !== "comment") return;
+      reset();
+      onComment?.(
+        currentFilePath,
+        meta.startLine,
+        meta.endLine,
+        meta.side,
+        text,
+      );
+    },
+    [currentFilePath, commentAnnotation, reset, onComment],
+  );
+
+  const handleRevert = useCallback(
+    async (hunkIndex: number) => {
+      const filePath = filePathRef.current;
+      if (!filePath) return;
+
+      setRevertingHunks((prev) => new Set(prev).add(hunkIndex));
+      setFileDiff((prev) => diffAcceptRejectHunk(prev, hunkIndex, "reject"));
+
+      try {
+        const [originalContent, modifiedContent] = await Promise.all([
+          trpcClient.git.getFileAtHead.query({
+            directoryPath: repoPath,
+            filePath,
+          }),
+          trpcClient.fs.readRepoFile.query({
+            repoPath,
+            filePath,
+          }),
+        ]);
+
+        const fullDiff = parseDiffFromFile(
+          { name: filePath, contents: originalContent ?? "" },
+          { name: filePath, contents: modifiedContent ?? "" },
+        );
+
+        const reverted = diffAcceptRejectHunk(fullDiff, hunkIndex, "reject");
+        const newContent = reverted.additionLines.join("");
+
+        await trpcClient.fs.writeRepoFile.mutate({
+          repoPath,
+          filePath,
+          content: newContent,
+        });
+
+        queryClient.invalidateQueries(
+          trpc.git.getDiffHead.queryFilter({ directoryPath: repoPath }),
+        );
+        queryClient.invalidateQueries(
+          trpc.git.getChangedFilesHead.queryFilter({ directoryPath: repoPath }),
+        );
+      } catch {
+        setFileDiff(initialFileDiff);
+      } finally {
+        setRevertingHunks((prev) => {
+          const next = new Set(prev);
+          next.delete(hunkIndex);
+          return next;
+        });
+      }
+    },
+    [repoPath, initialFileDiff, queryClient, trpc],
+  );
+
+  const renderAnnotation = useCallback(
+    (annotation: DiffLineAnnotation<AnnotationMetadata>) => {
+      if (annotation.metadata.kind === "comment") {
+        return (
+          <CommentAnnotation onSubmit={handleCommentSubmit} onCancel={reset} />
+        );
+      }
+
+      if (annotation.metadata.kind !== "hunk-revert") return null;
+      const { hunkIndex } = annotation.metadata;
+      const isReverting = revertingHunks.has(hunkIndex);
+
+      return (
+        <div className="relative w-full overflow-visible" style={{ height: 0 }}>
+          <button
+            type="button"
+            disabled={isReverting}
+            onClick={() => handleRevert(hunkIndex)}
+            className={`absolute top-0 right-2 inline-flex items-center gap-0.5 rounded border-none text-white transition-opacity ${
+              isReverting ? "opacity-60" : "opacity-0 hover:opacity-100"
+            }`}
+            style={{
+              background: "var(--red-9)",
+              padding: "1px 6px",
+              fontSize: "10px",
+              fontWeight: 500,
+              lineHeight: "18px",
+              cursor: isReverting ? "default" : "pointer",
+              zIndex: 10,
+            }}
+          >
+            <ArrowCounterClockwise size={12} />
+            {isReverting ? "Reverting..." : "Revert"}
+          </button>
+        </div>
+      );
+    },
+    [handleRevert, handleCommentSubmit, reset, revertingHunks],
+  );
+
+  const mergedOptions = useMemo(
+    () =>
+      buildCommentMergedOptions(
+        options,
+        hasOpenComment,
+        handleLineSelectionEnd,
+      ),
+    [options, hasOpenComment, handleLineSelectionEnd],
+  );
+
+  return (
+    <FileDiff
+      fileDiff={fileDiff}
+      options={mergedOptions}
+      lineAnnotations={annotations}
+      selectedLines={selectedRange}
+      renderAnnotation={renderAnnotation}
+      renderCustomHeader={renderCustomHeader}
+    />
+  );
+}
+
+function FilesDiffView({
+  oldFile,
+  newFile,
+  options,
+  renderCustomHeader,
+  onComment,
+}: FilesDiffProps) {
+  const {
+    selectedRange,
+    commentAnnotation,
+    hasOpenComment,
+    reset,
+    handleLineSelectionEnd,
+  } = useCommentState();
+
+  const filePath = newFile.name || oldFile.name;
+
+  const annotations = useMemo(
+    () => (commentAnnotation ? [commentAnnotation] : []),
+    [commentAnnotation],
+  );
+
+  const handleCommentSubmit = useCallback(
+    (text: string) => {
+      const meta = commentAnnotation?.metadata;
+      if (!filePath || !meta || meta.kind !== "comment") return;
+      reset();
+      onComment?.(filePath, meta.startLine, meta.endLine, meta.side, text);
+    },
+    [filePath, commentAnnotation, reset, onComment],
+  );
+
+  const renderAnnotation = useCallback(
+    (annotation: DiffLineAnnotation<AnnotationMetadata>) => {
+      if (annotation.metadata.kind !== "comment") return null;
+      return (
+        <CommentAnnotation onSubmit={handleCommentSubmit} onCancel={reset} />
+      );
+    },
+    [handleCommentSubmit, reset],
+  );
+
+  const mergedOptions = useMemo(
+    () =>
+      buildCommentMergedOptions(
+        options,
+        hasOpenComment,
+        handleLineSelectionEnd,
+      ),
+    [options, hasOpenComment, handleLineSelectionEnd],
+  );
+
+  return (
+    <MultiFileDiff
+      oldFile={oldFile}
+      newFile={newFile}
+      options={mergedOptions}
+      lineAnnotations={annotations}
+      selectedLines={selectedRange}
+      renderAnnotation={renderAnnotation}
+      renderCustomHeader={renderCustomHeader}
+    />
+  );
+}
diff --git a/apps/code/src/renderer/features/code-review/components/RevertableFileDiff.tsx b/apps/code/src/renderer/features/code-review/components/RevertableFileDiff.tsx
deleted file mode 100644
index d27aa15b4..000000000
--- a/apps/code/src/renderer/features/code-review/components/RevertableFileDiff.tsx
+++ /dev/null
@@ -1,181 +0,0 @@
-import { ArrowCounterClockwise } from "@phosphor-icons/react";
-import {
-  type DiffLineAnnotation,
-  diffAcceptRejectHunk,
-  type FileDiffMetadata,
-  type FileDiffOptions,
-  parseDiffFromFile,
-} from "@pierre/diffs";
-import { FileDiff } from "@pierre/diffs/react";
-import { trpcClient, useTRPC } from "@renderer/trpc/client";
-import { useQueryClient } from "@tanstack/react-query";
-import { useCallback, useMemo, useState } from "react";
-
-interface HunkRevertMetadata {
-  kind: "hunk-revert";
-  hunkIndex: number;
-}
-
-export type ReviewAnnotationMetadata = HunkRevertMetadata;
-
-function getLastChangeLineNumber(
-  hunk: FileDiffMetadata["hunks"][number],
-): number {
-  let lastChangeLine = hunk.additionStart;
-  let offset = 0;
-  for (const content of hunk.hunkContent) {
-    if (content.type === "change") {
-      lastChangeLine = hunk.additionStart + offset + content.additions - 1;
-    }
-    if (content.type === "context") offset += content.lines;
-    if (content.type === "change") offset += content.additions;
-  }
-  return lastChangeLine;
-}
-
-function buildHunkAnnotations(
-  fileDiff: FileDiffMetadata,
-): DiffLineAnnotation<ReviewAnnotationMetadata>[] {
-  return fileDiff.hunks
-    .filter((h) => h.additionLines > 0 || h.deletionLines > 0)
-    .map((hunk) => {
-      const hunkIndex = fileDiff.hunks.indexOf(hunk);
-      return {
-        side: "additions" as const,
-        lineNumber: getLastChangeLineNumber(hunk),
-        metadata: { kind: "hunk-revert" as const, hunkIndex },
-      };
-    });
-}
-
-interface RevertableFileDiffProps {
-  fileDiff: FileDiffMetadata;
-  repoPath: string;
-  options: FileDiffOptions<ReviewAnnotationMetadata>;
-  renderCustomHeader: (fd: FileDiffMetadata) => React.ReactNode;
-}
-
-export function RevertableFileDiff({
-  fileDiff: initialFileDiff,
-  repoPath,
-  options,
-  renderCustomHeader,
-}: RevertableFileDiffProps) {
-  const trpc = useTRPC();
-  const queryClient = useQueryClient();
-  const [fileDiff, setFileDiff] = useState(initialFileDiff);
-  const [revertingHunks, setRevertingHunks] = useState<Set<number>>(
-    () => new Set(),
-  );
-
-  // Sync with parent when the diff data changes (e.g. after query refetch)
-  const [lastInitial, setLastInitial] = useState(initialFileDiff);
-  if (initialFileDiff !== lastInitial) {
-    setLastInitial(initialFileDiff);
-    setFileDiff(initialFileDiff);
-    setRevertingHunks(new Set());
-  }
-
-  const annotations = useMemo(() => buildHunkAnnotations(fileDiff), [fileDiff]);
-
-  const handleRevert = useCallback(
-    async (hunkIndex: number) => {
-      const filePath = fileDiff.name ?? fileDiff.prevName ?? "";
-      if (!filePath) return;
-
-      setRevertingHunks((prev) => new Set(prev).add(hunkIndex));
-      setFileDiff((prev) => diffAcceptRejectHunk(prev, hunkIndex, "reject"));
-
-      try {
-        const [originalContent, modifiedContent] = await Promise.all([
-          trpcClient.git.getFileAtHead.query({
-            directoryPath: repoPath,
-            filePath,
-          }),
-          trpcClient.fs.readRepoFile.query({ repoPath, filePath }),
-        ]);
-
-        const fullDiff = parseDiffFromFile(
-          { name: filePath, contents: originalContent ?? "" },
-          { name: filePath, contents: modifiedContent ?? "" },
-        );
-
-        const reverted = diffAcceptRejectHunk(fullDiff, hunkIndex, "reject");
-        const newContent = reverted.additionLines.join("");
-
-        await trpcClient.fs.writeRepoFile.mutate({
-          repoPath,
-          filePath,
-          content: newContent,
-        });
-
-        queryClient.invalidateQueries(
-          trpc.git.getDiffHead.queryFilter({ directoryPath: repoPath }),
-        );
-        queryClient.invalidateQueries(
-          trpc.git.getChangedFilesHead.queryFilter({ directoryPath: repoPath }),
-        );
-      } catch {
-        setFileDiff(initialFileDiff);
-      } finally {
-        setRevertingHunks((prev) => {
-          const next = new Set(prev);
-          next.delete(hunkIndex);
-          return next;
-        });
-      }
-    },
-    [fileDiff, repoPath, initialFileDiff, queryClient, trpc],
-  );
-
-  const renderAnnotation = useCallback(
-    (annotation: DiffLineAnnotation<ReviewAnnotationMetadata>) => {
-      if (annotation.metadata.kind !== "hunk-revert") return null;
-      const isReverting = revertingHunks.has(annotation.metadata.hunkIndex);
-
-      return (
-        <div className="relative w-full overflow-visible" style={{ height: 0 }}>
-          <button
-            type="button"
-            disabled={isReverting}
-            onClick={() => handleRevert(annotation.metadata.hunkIndex)}
-            className={`absolute top-0 right-2 inline-flex items-center gap-0.5 rounded border-none text-white transition-opacity ${
-              isReverting ? "opacity-60" : "opacity-0 hover:opacity-100"
-            }`}
-            style={{
-              background: "var(--red-9)",
-              padding: "1px 6px",
-              fontSize: "10px",
-              fontWeight: 500,
-              lineHeight: "18px",
-              cursor: isReverting ? "default" : "pointer",
-              zIndex: 10,
-            }}
-          >
-            <ArrowCounterClockwise size={12} />
-            {isReverting ? "Reverting..." : "Revert"}
-          </button>
-        </div>
-      );
-    },
-    [handleRevert, revertingHunks],
-  );
-
-  const mergedOptions = useMemo(
-    () => ({
-      ...options,
-      unsafeCSS: `${(options.unsafeCSS as string) ?? ""} [data-line-annotation] { height: 0; min-height: 0; overflow: visible; }`,
-    }),
-    [options],
-  );
-
-  return (
-    <FileDiff
-      fileDiff={fileDiff}
-      options={mergedOptions}
-      lineAnnotations={annotations}
-      renderAnnotation={renderAnnotation}
-      renderCustomHeader={renderCustomHeader}
-    />
-  );
-}
diff --git a/apps/code/src/renderer/features/code-review/components/ReviewPage.tsx b/apps/code/src/renderer/features/code-review/components/ReviewPage.tsx
index 877c7c801..8c0c844fb 100644
--- a/apps/code/src/renderer/features/code-review/components/ReviewPage.tsx
+++ b/apps/code/src/renderer/features/code-review/components/ReviewPage.tsx
@@ -2,14 +2,15 @@ import { useDiffViewerStore } from "@features/code-editor/stores/diffViewerStore
 import { useGitQueries } from "@features/git-interaction/hooks/useGitQueries";
 import { usePanelLayoutStore } from "@features/panels/store/panelLayoutStore";
 import { useCwd } from "@features/sidebar/hooks/useCwd";
-import { type FileDiffOptions, parsePatchFiles } from "@pierre/diffs";
-import { MultiFileDiff } from "@pierre/diffs/react";
+import { parsePatchFiles } from "@pierre/diffs";
 import { Flex, Text } from "@radix-ui/themes";
 import { useTRPC } from "@renderer/trpc/client";
 import type { ChangedFile } from "@shared/types";
 import { useQuery } from "@tanstack/react-query";
 import { useMemo } from "react";
-import { RevertableFileDiff } from "./RevertableFileDiff";
+import { useReviewComment } from "../hooks/useReviewComment";
+import type { DiffOptions, OnCommentCallback } from "../types";
+import { InteractiveFileDiff } from "./InteractiveFileDiff";
 import {
   DeferredDiffPlaceholder,
   DiffFileHeader,
@@ -28,6 +29,7 @@ export function ReviewPage({ taskId }: ReviewPageProps) {
   const { changedFiles, changesLoading } = useGitQueries(repoPath);
   const hideWhitespace = useDiffViewerStore((s) => s.hideWhitespaceChanges);
   const openFile = usePanelLayoutStore((s) => s.openFile);
+  const onComment = useReviewComment(taskId);
 
   const { data: rawDiff, isLoading: diffLoading } = useQuery(
     trpc.git.getDiffHead.queryOptions(
@@ -117,10 +119,11 @@ export function ReviewPage({ taskId }: ReviewPageProps) {
 
         return (
           <div key={key} data-file-path={key}>
-            <RevertableFileDiff
+            <InteractiveFileDiff
               fileDiff={fileDiff}
               repoPath={repoPath}
               options={{ ...diffOptions, collapsed: isCollapsed }}
+              onComment={onComment}
               renderCustomHeader={(fd) => (
                 <DiffFileHeader
                   fileDiff={fd}
@@ -145,6 +148,7 @@ export function ReviewPage({ taskId }: ReviewPageProps) {
               options={diffOptions}
               collapsed={isCollapsed}
               onToggle={() => toggleFile(file.path)}
+              onComment={onComment}
             />
           </div>
         );
@@ -159,12 +163,14 @@ function UntrackedFileDiff({
   options,
   collapsed,
   onToggle,
+  onComment,
 }: {
   file: ChangedFile;
   repoPath: string;
-  options: FileDiffOptions<unknown>;
+  options: DiffOptions;
   collapsed: boolean;
   onToggle: () => void;
+  onComment: OnCommentCallback;
 }) {
   const trpc = useTRPC();
   const { data: content } = useQuery(
@@ -182,10 +188,11 @@ function UntrackedFileDiff({
   );
 
   return (
-    <MultiFileDiff
+    <InteractiveFileDiff
       oldFile={oldFile}
       newFile={newFile}
       options={{ ...options, collapsed }}
+      onComment={onComment}
       renderCustomHeader={(fd) => (
         <DiffFileHeader
           fileDiff={fd}
diff --git a/apps/code/src/renderer/features/code-review/hooks/useCommentState.ts b/apps/code/src/renderer/features/code-review/hooks/useCommentState.ts
new file mode 100644
index 000000000..8cc5f3a93
--- /dev/null
+++ b/apps/code/src/renderer/features/code-review/hooks/useCommentState.ts
@@ -0,0 +1,49 @@
+import type {
+  AnnotationSide,
+  DiffLineAnnotation,
+  SelectedLineRange,
+} from "@pierre/diffs";
+import { useCallback, useState } from "react";
+import type { AnnotationMetadata } from "../types";
+
+export function useCommentState() {
+  const [selectedRange, setSelectedRange] = useState<SelectedLineRange | null>(
+    null,
+  );
+  const [commentAnnotation, setCommentAnnotation] =
+    useState<DiffLineAnnotation<AnnotationMetadata> | null>(null);
+
+  const hasOpenComment = commentAnnotation !== null;
+
+  const reset = useCallback(() => {
+    setCommentAnnotation(null);
+    setSelectedRange(null);
+  }, []);
+
+  const handleLineSelectionEnd = useCallback(
+    (range: SelectedLineRange | null) => {
+      setSelectedRange(range);
+      if (range == null) return;
+      const derivedSide = range.endSide ?? range.side;
+      const side: AnnotationSide =
+        derivedSide === "deletions" ? "deletions" : "additions";
+      const startLine = Math.min(range.start, range.end);
+      const endLine = Math.max(range.start, range.end);
+
+      setCommentAnnotation({
+        side,
+        lineNumber: endLine,
+        metadata: { kind: "comment", startLine, endLine, side },
+      });
+    },
+    [],
+  );
+
+  return {
+    selectedRange,
+    commentAnnotation,
+    hasOpenComment,
+    reset,
+    handleLineSelectionEnd,
+  };
+}
diff --git a/apps/code/src/renderer/features/code-review/hooks/useReviewComment.ts b/apps/code/src/renderer/features/code-review/hooks/useReviewComment.ts
new file mode 100644
index 000000000..b0dbca403
--- /dev/null
+++ b/apps/code/src/renderer/features/code-review/hooks/useReviewComment.ts
@@ -0,0 +1,41 @@
+import { DEFAULT_TAB_IDS } from "@features/panels/constants/panelConstants";
+import { usePanelLayoutStore } from "@features/panels/store/panelLayoutStore";
+import { findTabInTree } from "@features/panels/store/panelTree";
+import { getSessionService } from "@features/sessions/service/service";
+import { useCallback } from "react";
+import type { OnCommentCallback } from "../types";
+
+function escapeXmlAttr(value: string): string {
+  return value
+    .replace(/&/g, "&amp;")
+    .replace(/</g, "&lt;")
+    .replace(/>/g, "&gt;")
+    .replace(/"/g, "&quot;")
+    .replace(/'/g, "&apos;");
+}
+
+export function useReviewComment(taskId: string): OnCommentCallback {
+  return useCallback(
+    (filePath, startLine, endLine, side, comment) => {
+      const lineRef =
+        startLine === endLine
+          ? `line ${startLine}`
+          : `lines ${startLine}-${endLine}`;
+      const sideLabel = side === "deletions" ? "old" : "new";
+      const escapedPath = escapeXmlAttr(filePath);
+      const prompt = `In file <file path="${escapedPath}" />, ${lineRef} (${sideLabel}):\n\n${comment}`;
+
+      getSessionService().sendPrompt(taskId, prompt);
+
+      const { taskLayouts, setActiveTab } = usePanelLayoutStore.getState();
+      const layout = taskLayouts[taskId];
+      if (layout) {
+        const result = findTabInTree(layout.panelTree, DEFAULT_TAB_IDS.LOGS);
+        if (result) {
+          setActiveTab(taskId, result.panelId, DEFAULT_TAB_IDS.LOGS);
+        }
+      }
+    },
+    [taskId],
+  );
+}
diff --git a/apps/code/src/renderer/features/code-review/types.ts b/apps/code/src/renderer/features/code-review/types.ts
new file mode 100644
index 000000000..704f2e4a9
--- /dev/null
+++ b/apps/code/src/renderer/features/code-review/types.ts
@@ -0,0 +1,37 @@
+import type { AnnotationSide, FileDiffOptions } from "@pierre/diffs";
+import type { FileDiffProps, MultiFileDiffProps } from "@pierre/diffs/react";
+
+export interface HunkRevertMetadata {
+  kind: "hunk-revert";
+  hunkIndex: number;
+}
+
+export interface CommentMetadata {
+  kind: "comment";
+  startLine: number;
+  endLine: number;
+  side: AnnotationSide;
+}
+
+export type AnnotationMetadata = HunkRevertMetadata | CommentMetadata;
+
+export type DiffOptions = FileDiffOptions<AnnotationMetadata>;
+
+export type OnCommentCallback = (
+  filePath: string,
+  startLine: number,
+  endLine: number,
+  side: AnnotationSide,
+  comment: string,
+) => void;
+
+export type PatchDiffProps = FileDiffProps<AnnotationMetadata> & {
+  repoPath: string;
+  onComment?: OnCommentCallback;
+};
+
+export type FilesDiffProps = MultiFileDiffProps<AnnotationMetadata> & {
+  onComment?: OnCommentCallback;
+};
+
+export type InteractiveFileDiffProps = PatchDiffProps | FilesDiffProps;
diff --git a/apps/code/src/renderer/features/code-review/utils/diffAnnotations.ts b/apps/code/src/renderer/features/code-review/utils/diffAnnotations.ts
new file mode 100644
index 000000000..e817b943f
--- /dev/null
+++ b/apps/code/src/renderer/features/code-review/utils/diffAnnotations.ts
@@ -0,0 +1,49 @@
+import type {
+  DiffLineAnnotation,
+  FileDiffMetadata,
+  SelectedLineRange,
+} from "@pierre/diffs";
+import type { AnnotationMetadata, DiffOptions } from "../types";
+
+export function getLastChangeLineNumber(
+  hunk: FileDiffMetadata["hunks"][number],
+): number {
+  let lastChangeLine = hunk.additionStart;
+  let offset = 0;
+  for (const content of hunk.hunkContent) {
+    if (content.type === "change") {
+      lastChangeLine = hunk.additionStart + offset + content.additions - 1;
+    }
+    if (content.type === "context") offset += content.lines;
+    if (content.type === "change") offset += content.additions;
+  }
+  return lastChangeLine;
+}
+
+export function buildHunkAnnotations(
+  fileDiff: FileDiffMetadata,
+): DiffLineAnnotation<AnnotationMetadata>[] {
+  return fileDiff.hunks.flatMap((hunk, hunkIndex) => {
+    if (hunk.additionLines === 0 && hunk.deletionLines === 0) return [];
+    return [
+      {
+        side: "additions" as const,
+        lineNumber: getLastChangeLineNumber(hunk),
+        metadata: { kind: "hunk-revert" as const, hunkIndex },
+      },
+    ];
+  });
+}
+
+export function buildCommentMergedOptions(
+  options: DiffOptions | undefined,
+  hasOpenComment: boolean,
+  handleLineSelectionEnd: (range: SelectedLineRange | null) => void,
+): DiffOptions {
+  return {
+    ...options,
+    enableLineSelection: !hasOpenComment,
+    enableGutterUtility: !hasOpenComment,
+    onLineSelectionEnd: handleLineSelectionEnd,
+  };
+}