diff --git a/docs/dashboard-guide.md b/docs/dashboard-guide.md
index 2d0b1b1258..fb90c2d0bb 100644
--- a/docs/dashboard-guide.md
+++ b/docs/dashboard-guide.md
@@ -450,6 +450,7 @@ Features:
 - Open project markdown files with inline preview
 - Jump directly from a document group to the owning task detail modal
 - Toggle between raw text and rendered markdown using the **Markdown/Plain** button
+- Highlight text in raw or rendered project-file previews, choose **Add comment**, and send the file path, selected snippet, and your comment to the **New Task** dialog
 
 ![Documents view](./screenshots/documents-view.png)
 
@@ -480,6 +481,8 @@ Documents view supports toggling between raw text and formatted markdown when vi
 
 The toggle button is accessible with `aria-pressed` for screen readers. Toggle state is scoped per-document, so switching between documents resets the view to raw mode.
 
+Project-file previews also support selection comments in both raw and rendered markdown modes. Select text, click **Add comment**, enter a short note, and Fusion opens **New Task** with a seeded description containing the file path, snippet, and comment.
+
 ## Todo View
 
 Todo View is an experimental dashboard surface for managing per-project todo lists and turning items into planning or task workflows.
@@ -523,10 +526,11 @@ The Files modal provides a workspace-aware file browser and editor.
 - Use **New File** or **New Folder** in the browser header to create entries in the current folder; new files open in the editor after creation
 - Source/text editing supports a **Line #** header toggle to show or hide line numbers in the editor gutter
 - The line-number preference is saved per project and restored automatically when you switch projects
+- In editable files and markdown preview mode, highlighted text exposes **Add comment** so you can send the file path, selected snippet, best-effort line range, and your note to the **New Task** dialog without copy/paste
 
 ## Memory View
 
-Memory view provides a multi-file editor for project and daily memory files.
+Memory view provides a multi-file editor for project and daily memory files. Its file editors share the same highlighted-text **Add comment** affordance as the Files modal, so memory snippets can seed a New Task with file path, snippet, and comment context.
 
 > Available when the `experimentalFeatures.memoryView` toggle is enabled.
 
diff --git a/packages/dashboard/app/App.tsx b/packages/dashboard/app/App.tsx
index de4c0cc669..0f5baed30e 100644
--- a/packages/dashboard/app/App.tsx
+++ b/packages/dashboard/app/App.tsx
@@ -1696,6 +1696,7 @@ function AppInner() {
               projectId={currentProject?.id}
               addToast={addToast}
               onOpenDetail={openDetailTask}
+              onSendSelectionToTask={modalManager.openNewTaskWithDescription}
             />
           </Suspense>
         </PageErrorBoundary>
@@ -1786,7 +1787,11 @@ function AppInner() {
       return (
         <PageErrorBoundary>
           <Suspense fallback={null}>
-            <MemoryView addToast={addToast} projectId={currentProject?.id} />
+            <MemoryView
+              addToast={addToast}
+              projectId={currentProject?.id}
+              onSendSelectionToTask={modalManager.openNewTaskWithDescription}
+            />
           </Suspense>
         </PageErrorBoundary>
       );
diff --git a/packages/dashboard/app/components/AppModals.tsx b/packages/dashboard/app/components/AppModals.tsx
index c626cd2700..efc15e1098 100644
--- a/packages/dashboard/app/components/AppModals.tsx
+++ b/packages/dashboard/app/components/AppModals.tsx
@@ -404,6 +404,7 @@ export function AppModals({
           onClose={closeFilesWithNav}
           onWorkspaceChange={modalManager.setFileWorkspace}
           projectId={projectId}
+          onSendSelectionToTask={modalManager.openNewTaskWithDescription}
         />
       )}
 
@@ -446,6 +447,7 @@ export function AppModals({
           onCreateTask={handleModalCreateWithOnboardingTracking}
           addToast={addToast}
           projectId={projectId}
+          initialDescription={modalManager.newTaskInitialDescription ?? ""}
         />
       </ModalErrorBoundary>
 
diff --git a/packages/dashboard/app/components/DocumentsView.tsx b/packages/dashboard/app/components/DocumentsView.tsx
index 031834954b..ff38a3a8b3 100644
--- a/packages/dashboard/app/components/DocumentsView.tsx
+++ b/packages/dashboard/app/components/DocumentsView.tsx
@@ -9,6 +9,8 @@ import type { ToastType } from "../hooks/useToast";
 import { fetchTaskDetail, fetchWorkspaceFileContent, type MarkdownFileEntry } from "../api";
 import { useDocuments } from "../hooks/useDocuments";
 import { useProjectMarkdownFiles } from "../hooks/useProjectMarkdownFiles";
+import { useSelectionComment } from "../hooks/useSelectionComment";
+import { SelectionCommentPopover } from "./SelectionCommentPopover";
 
 const MOBILE_BREAKPOINT = 768;
 
@@ -18,6 +20,7 @@ export interface DocumentsViewProps {
   projectId?: string;
   addToast: (message: string, type?: ToastType) => void;
   onOpenDetail: (task: TaskDetail) => void;
+  onSendSelectionToTask?: (description: string) => void;
 }
 
 interface DocumentCardProps {
@@ -172,7 +175,7 @@ function TaskGroup({ taskId, taskTitle, documents, onOpenTask, renderMarkdownSta
   );
 }
 
-export function DocumentsView({ projectId, addToast, onOpenDetail }: DocumentsViewProps) {
+export function DocumentsView({ projectId, addToast, onOpenDetail, onSendSelectionToTask }: DocumentsViewProps) {
   const { t } = useTranslation("app");
   const [activeTab, setActiveTab] = useState<DocumentsTab>("project");
   const [searchQuery, setSearchQuery] = useState("");
@@ -184,10 +187,16 @@ export function DocumentsView({ projectId, addToast, onOpenDetail }: DocumentsVi
   const [isMobile, setIsMobile] = useState(false);
   const requestIdRef = useRef(0);
   const initialTabSetRef = useRef(false);
+  const markdownPreviewRef = useRef<HTMLDivElement>(null);
+  const plainPreviewRef = useRef<HTMLPreElement>(null);
   // Markdown render toggle for project file preview
   const [renderProjectMarkdown, setRenderProjectMarkdown] = useState(false);
   // Markdown render toggles per task document card (scoped by doc ID)
   const [taskDocMarkdownStates, setTaskDocMarkdownStates] = useState<Map<string, boolean>>(new Map());
+  const [selectionCommentOpen, setSelectionCommentOpen] = useState(false);
+  const markdownSelection = useSelectionComment(markdownPreviewRef, { locked: selectionCommentOpen });
+  const plainSelection = useSelectionComment(plainPreviewRef, { locked: selectionCommentOpen });
+  const activeProjectSelection = renderProjectMarkdown ? markdownSelection : plainSelection;
 
   const taskSearchQuery = activeTab === "tasks" ? searchQuery.trim() : "";
 
@@ -374,6 +383,15 @@ export function DocumentsView({ projectId, addToast, onOpenDetail }: DocumentsVi
   }, [activeTab, refreshProjectFiles, refreshDocuments]);
 
   const activeCount = activeTab === "project" ? filteredProjectFiles.length : documents.length;
+  const selectionPopover = selectedFile && onSendSelectionToTask && activeProjectSelection ? (
+    <SelectionCommentPopover
+      selectedText={activeProjectSelection.selectedText}
+      anchorRect={activeProjectSelection.anchorRect}
+      filePath={selectedFile.path}
+      onSubmit={onSendSelectionToTask}
+      onOpenChange={setSelectionCommentOpen}
+    />
+  ) : null;
 
   const searchPlaceholder = activeTab === "project"
     ? t("documents.searchProjectFiles", "Search project markdown files…")
@@ -541,14 +559,15 @@ export function DocumentsView({ projectId, addToast, onOpenDetail }: DocumentsVi
                       ) : fileError ? (
                         <p className="documents-content-state documents-content-state--error">{fileError}</p>
                       ) : renderProjectMarkdown ? (
-                        <div className="documents-content-markdown">
+                        <div ref={markdownPreviewRef} className="documents-content-markdown">
                           <div className="markdown-body">
                             <ReactMarkdown remarkPlugins={[remarkGfm]}>{fileContent ?? ""}</ReactMarkdown>
                           </div>
                         </div>
                       ) : (
-                        <pre className="document-card-content-text documents-content-viewer-text">{fileContent ?? ""}</pre>
+                        <pre ref={plainPreviewRef} className="document-card-content-text documents-content-viewer-text">{fileContent ?? ""}</pre>
                       )}
+                      {selectionPopover}
                     </div>
                   )}
                 </section>
diff --git a/packages/dashboard/app/components/FileBrowserModal.tsx b/packages/dashboard/app/components/FileBrowserModal.tsx
index ba6d10d256..b012c4fe0c 100644
--- a/packages/dashboard/app/components/FileBrowserModal.tsx
+++ b/packages/dashboard/app/components/FileBrowserModal.tsx
@@ -63,6 +63,7 @@ interface FileBrowserModalProps {
   onClose: () => void;
   onWorkspaceChange?: (workspace: string) => void;
   projectId?: string;
+  onSendSelectionToTask?: (description: string) => void;
 }
 
 /**
@@ -75,6 +76,7 @@ export function FileBrowserModal({
   onClose,
   onWorkspaceChange,
   projectId,
+  onSendSelectionToTask,
 }: FileBrowserModalProps) {
   const { t } = useTranslation("app");
   const { projectName, workspaces } = useWorkspaces(projectId);
@@ -451,6 +453,7 @@ export function FileBrowserModal({
                       canToggleLineNumbers={!isBinaryFile(selectedFile)}
                       toolbarExpanded={toolbarActionsExpanded}
                       toolbarActionsId={toolbarActionsId}
+                      onSendSelectionToTask={onSendSelectionToTask}
                     />
                   </div>
                 )}
diff --git a/packages/dashboard/app/components/FileEditor.tsx b/packages/dashboard/app/components/FileEditor.tsx
index 3c0cc851d6..060076455e 100644
--- a/packages/dashboard/app/components/FileEditor.tsx
+++ b/packages/dashboard/app/components/FileEditor.tsx
@@ -7,6 +7,8 @@ import { EditorView, lineNumbers } from "@codemirror/view";
 import { EditorState, Compartment, type Extension } from "@codemirror/state";
 import { syntaxHighlighting, defaultHighlightStyle } from "@codemirror/language";
 import { oneDark } from "@codemirror/theme-one-dark";
+import { useSelectionComment } from "../hooks/useSelectionComment";
+import { SelectionCommentPopover } from "./SelectionCommentPopover";
 import { resolveCodeMirrorLanguage } from "../utils/codemirror-language";
 
 interface FileEditorProps {
@@ -19,6 +21,7 @@ interface FileEditorProps {
   canToggleLineNumbers?: boolean;
   toolbarExpanded?: boolean;
   toolbarActionsId?: string;
+  onSendSelectionToTask?: (description: string) => void;
 }
 
 const FILE_EDITOR_MARKDOWN_PREVIEW_STORAGE_KEY = "fn-file-editor-markdown-preview";
@@ -67,6 +70,7 @@ export function FileEditor({
   canToggleLineNumbers = true,
   toolbarExpanded,
   toolbarActionsId: externalToolbarActionsId,
+  onSendSelectionToTask,
 }: FileEditorProps) {
   const { t } = useTranslation("app");
   /*
@@ -80,6 +84,7 @@ export function FileEditor({
   const expanded = isControlled ? toolbarExpanded : internalExpanded;
 
   const editorHostRef = useRef<HTMLDivElement>(null);
+  const previewRef = useRef<HTMLDivElement>(null);
   const editorViewRef = useRef<EditorView | null>(null);
   const syncingFromPropsRef = useRef(false);
   const onChangeRef = useRef(onChange);
@@ -111,6 +116,33 @@ export function FileEditor({
     }
   }, [isControlled]);
 
+  const [selectionCommentOpen, setSelectionCommentOpen] = useState(false);
+  const getCodeMirrorLineRange = useCallback(() => {
+    const view = editorViewRef.current;
+    if (!view) return undefined;
+    const range = view.state.selection.main;
+    if (range.empty) return undefined;
+    const fromLine = view.state.doc.lineAt(Math.min(range.from, range.to)).number;
+    const toLine = view.state.doc.lineAt(Math.max(range.from, range.to)).number;
+    return { start: fromLine, end: toLine };
+  }, []);
+  const editorSelection = useSelectionComment(editorHostRef, {
+    locked: selectionCommentOpen,
+    getLineRange: getCodeMirrorLineRange,
+  });
+  const previewSelection = useSelectionComment(previewRef, { locked: selectionCommentOpen });
+  const activeSelection = effectiveShowPreview ? previewSelection : editorSelection;
+  const selectionPopover = onSendSelectionToTask && activeSelection ? (
+    <SelectionCommentPopover
+      selectedText={activeSelection.selectedText}
+      anchorRect={activeSelection.anchorRect}
+      filePath={filePath}
+      lineRange={activeSelection.lineRange}
+      onSubmit={onSendSelectionToTask}
+      onOpenChange={setSelectionCommentOpen}
+    />
+  ) : null;
+
   useEffect(() => {
     writeBooleanPref(FILE_EDITOR_MARKDOWN_PREVIEW_STORAGE_KEY, showPreview);
   }, [showPreview]);
@@ -254,12 +286,13 @@ export function FileEditor({
       ) : null}
 
       {effectiveShowPreview ? (
-        <div className="file-editor-preview markdown-body">
+        <div ref={previewRef} className="file-editor-preview markdown-body">
           <ReactMarkdown remarkPlugins={[remarkGfm]}>{content}</ReactMarkdown>
         </div>
       ) : (
         <div className="file-editor-codemirror" ref={editorHostRef} aria-label={filePath ? t("fileEditor.editorFor", `Editor for ${filePath}`) : t("fileEditor.fileEditor", "File editor")} />
       )}
+      {selectionPopover}
     </div>
   );
 }
diff --git a/packages/dashboard/app/components/MemoryView.tsx b/packages/dashboard/app/components/MemoryView.tsx
index 1862739efe..7770ad5582 100644
--- a/packages/dashboard/app/components/MemoryView.tsx
+++ b/packages/dashboard/app/components/MemoryView.tsx
@@ -10,6 +10,7 @@ import { useMemoryData } from "../hooks/useMemoryData";
 interface MemoryViewProps {
   projectId?: string;
   addToast: (message: string, type: "success" | "error" | "info") => void;
+  onSendSelectionToTask?: (description: string) => void;
 }
 
 type Tab = "working" | "insights" | "engines";
@@ -98,7 +99,7 @@ function countTotalInsights(categories: ParsedInsightCategory[]): number {
   return categories.reduce((sum, cat) => sum + cat.items.length, 0);
 }
 
-export function MemoryView({ projectId, addToast }: MemoryViewProps) {
+export function MemoryView({ projectId, addToast, onSendSelectionToTask }: MemoryViewProps) {
   const { t } = useTranslation("app");
   const [activeTab, setActiveTab] = useState<Tab>("working");
   const [expandedCategories, setExpandedCategories] = useState<Set<string>>(new Set());
@@ -454,6 +455,7 @@ export function MemoryView({ projectId, addToast }: MemoryViewProps) {
                         onChange={setSelectedFileContent}
                         readOnly={!isWritable}
                         filePath={selectedFilePath}
+                        onSendSelectionToTask={onSendSelectionToTask}
                       />
                     </div>
                   </div>
@@ -671,6 +673,7 @@ export function MemoryView({ projectId, addToast }: MemoryViewProps) {
                     onChange={setInsightsEditorContent}
                     readOnly={false}
                     filePath=".fusion/memory/INSIGHTS.md"
+                    onSendSelectionToTask={onSendSelectionToTask}
                   />
                 </div>
                 <div className="memory-action-bar">
diff --git a/packages/dashboard/app/components/NewTaskModal.tsx b/packages/dashboard/app/components/NewTaskModal.tsx
index 8214096e37..7734233c15 100644
--- a/packages/dashboard/app/components/NewTaskModal.tsx
+++ b/packages/dashboard/app/components/NewTaskModal.tsx
@@ -24,9 +24,10 @@ interface NewTaskModalProps {
   tasks: Task[]; // for dependency selection
   onCreateTask: (input: TaskCreateInput) => Promise<Task>;
   addToast: (message: string, type?: ToastType) => void;
+  initialDescription?: string;
 }
 
-export function NewTaskModal({ isOpen, onClose, projectId, tasks, onCreateTask, addToast }: NewTaskModalProps) {
+export function NewTaskModal({ isOpen, onClose, projectId, tasks, onCreateTask, addToast, initialDescription = "" }: NewTaskModalProps) {
   const { t } = useTranslation("app");
   const { confirm } = useConfirm();
   const viewportMode = useViewportMode();
@@ -42,6 +43,7 @@ export function NewTaskModal({ isOpen, onClose, projectId, tasks, onCreateTask,
       } as React.CSSProperties)
     : {};
   const [description, setDescription] = useState("");
+  const wasOpenRef = useRef(false);
   const [dependencies, setDependencies] = useState<string[]>([]);
   const [branchMode, setBranchMode] = useState<BranchSelectionMode>("project-default");
   const [branch, setBranch] = useState("");
@@ -80,6 +82,17 @@ export function NewTaskModal({ isOpen, onClose, projectId, tasks, onCreateTask,
   const { hasAiProvider, hasGithub, loading: setupReadinessLoading } = useSetupReadiness(projectId);
   const { nodes } = useNodes();
 
+  /**
+   * FNXC:SelectionComment 2026-06-16-23:58:
+   * Selection comments open the normal New Task dialog with a prefilled description; seed only on the closed→open transition so rerenders do not overwrite user edits.
+   */
+  useEffect(() => {
+    if (isOpen && !wasOpenRef.current) {
+      setDescription(initialDescription);
+    }
+    wasOpenRef.current = isOpen;
+  }, [initialDescription, isOpen]);
+
   // Load agents for agent picker
   const loadAgents = useCallback(() => {
     setShowAgentPicker(true);
diff --git a/packages/dashboard/app/components/SelectionCommentPopover.css b/packages/dashboard/app/components/SelectionCommentPopover.css
new file mode 100644
index 0000000000..83c1609803
--- /dev/null
+++ b/packages/dashboard/app/components/SelectionCommentPopover.css
@@ -0,0 +1,73 @@
+.selection-comment-trigger,
+.selection-comment-panel {
+  position: fixed;
+  z-index: 10001;
+  left: var(--selection-comment-left);
+  top: var(--selection-comment-top);
+}
+
+.selection-comment-trigger {
+  transform: translate(-50%, calc(-1 * var(--space-xl)));
+  box-shadow: var(--shadow-md);
+  white-space: nowrap;
+}
+
+.selection-comment-panel {
+  width: min(var(--selection-comment-panel-width, calc(var(--space-2xl) * 12)), calc(100vw - (var(--space-lg) * 2)));
+  transform: translate(-50%, var(--space-xs));
+  padding: var(--space-md);
+  display: flex;
+  flex-direction: column;
+  gap: var(--space-sm);
+  box-shadow: var(--shadow-lg);
+}
+
+.selection-comment-title {
+  margin: 0;
+  font-weight: 600;
+  color: var(--text);
+}
+
+.selection-comment-snippet {
+  margin: 0;
+  max-height: calc(var(--space-2xl) * 3);
+  overflow: auto;
+  color: var(--text-muted);
+  background: var(--surface-subtle);
+  border: 1px solid var(--border);
+  border-radius: var(--radius-sm);
+  padding: var(--space-sm);
+  font-family: var(--font-mono);
+  white-space: pre-wrap;
+}
+
+.selection-comment-actions {
+  display: flex;
+  justify-content: flex-end;
+  gap: var(--space-sm);
+}
+
+.selection-comment-textarea {
+  min-height: calc(var(--space-2xl) * 2.5);
+  resize: vertical;
+}
+
+@media (max-width: 768px) {
+  .selection-comment-trigger,
+  .selection-comment-panel {
+    left: max(var(--space-lg), min(var(--selection-comment-left), calc(100vw - var(--space-lg))));
+  }
+
+  .selection-comment-trigger {
+    transform: translate(-50%, calc(-1 * var(--space-2xl)));
+  }
+
+  .selection-comment-actions {
+    flex-direction: column-reverse;
+  }
+
+  .selection-comment-actions .btn {
+    width: 100%;
+    justify-content: center;
+  }
+}
diff --git a/packages/dashboard/app/components/SelectionCommentPopover.tsx b/packages/dashboard/app/components/SelectionCommentPopover.tsx
new file mode 100644
index 0000000000..efd8d8045e
--- /dev/null
+++ b/packages/dashboard/app/components/SelectionCommentPopover.tsx
@@ -0,0 +1,181 @@
+import "./SelectionCommentPopover.css";
+import { useCallback, useEffect, useMemo, useRef, useState, type CSSProperties } from "react";
+import { useTranslation } from "react-i18next";
+import { MessageSquarePlus } from "lucide-react";
+import type { SelectionCommentLineRange } from "../hooks/useSelectionComment";
+
+interface SelectionCommentPopoverProps {
+  selectedText: string;
+  anchorRect: DOMRect | null;
+  filePath?: string;
+  lineRange?: SelectionCommentLineRange;
+  onSubmit: (description: string) => void;
+  onCancel?: () => void;
+  onOpenChange?: (open: boolean) => void;
+}
+
+function buildFence(text: string): string {
+  let fence = "```";
+  while (text.includes(fence)) {
+    fence += "`";
+  }
+  return fence;
+}
+
+export function composeSelectionCommentDescription({
+  filePath,
+  selectedText,
+  comment,
+  lineRange,
+}: {
+  filePath?: string;
+  selectedText: string;
+  comment: string;
+  lineRange?: SelectionCommentLineRange;
+}): string {
+  const normalizedSnippet = selectedText.trim();
+  const normalizedComment = comment.trim();
+  const fence = buildFence(normalizedSnippet);
+  const lines = lineRange ? [`Lines: ${lineRange.start === lineRange.end ? lineRange.start : `${lineRange.start}-${lineRange.end}`}`, ""] : [];
+
+  return [
+    `File: ${filePath?.trim() || "Unknown file"}`,
+    ...lines,
+    "Selected snippet:",
+    `${fence}text`,
+    normalizedSnippet,
+    fence,
+    "",
+    "Comment:",
+    normalizedComment,
+  ].join("\n");
+}
+
+/**
+ * FNXC:SelectionComment 2026-06-16-23:56:
+ * The selected text affordance is intentionally stateless beyond a short comment: it formats file path, optional line range, snippet, and user note into a New Task description instead of adding a persistent review/comment model.
+ */
+export function SelectionCommentPopover({
+  selectedText,
+  anchorRect,
+  filePath,
+  lineRange,
+  onSubmit,
+  onCancel,
+  onOpenChange,
+}: SelectionCommentPopoverProps) {
+  const { t } = useTranslation("app");
+  const [expanded, setExpanded] = useState(false);
+  const [comment, setComment] = useState("");
+  const rootRef = useRef<HTMLDivElement>(null);
+  const textareaRef = useRef<HTMLTextAreaElement>(null);
+
+  const trimmedSelectedText = selectedText.trim();
+  const style = useMemo(() => {
+    if (!anchorRect) return undefined;
+    return {
+      "--selection-comment-left": `${anchorRect.left + anchorRect.width / 2}px`,
+      "--selection-comment-top": `${anchorRect.bottom}px`,
+    } as CSSProperties;
+  }, [anchorRect]);
+
+  useEffect(() => {
+    setExpanded(false);
+    setComment("");
+    onOpenChange?.(false);
+  }, [onOpenChange, trimmedSelectedText]);
+
+  useEffect(() => {
+    if (!expanded) return;
+    textareaRef.current?.focus();
+  }, [expanded]);
+
+  const setPanelExpanded = useCallback((open: boolean) => {
+    setExpanded(open);
+    onOpenChange?.(open);
+  }, [onOpenChange]);
+
+  const handleCancel = useCallback(() => {
+    setPanelExpanded(false);
+    setComment("");
+    onCancel?.();
+  }, [onCancel, setPanelExpanded]);
+
+  useEffect(() => {
+    if (!expanded) return;
+
+    const handleKeyDown = (event: KeyboardEvent) => {
+      if (event.key === "Escape") {
+        handleCancel();
+      }
+    };
+
+    const handlePointerDown = (event: PointerEvent) => {
+      if (rootRef.current && !rootRef.current.contains(event.target as Node)) {
+        handleCancel();
+      }
+    };
+
+    document.addEventListener("keydown", handleKeyDown);
+    document.addEventListener("pointerdown", handlePointerDown);
+    return () => {
+      document.removeEventListener("keydown", handleKeyDown);
+      document.removeEventListener("pointerdown", handlePointerDown);
+    };
+  }, [expanded, handleCancel]);
+
+  const handleSubmit = useCallback(() => {
+    const description = composeSelectionCommentDescription({
+      filePath,
+      selectedText: trimmedSelectedText,
+      comment,
+      lineRange,
+    });
+    onSubmit(description);
+    setPanelExpanded(false);
+    setComment("");
+  }, [comment, filePath, lineRange, onSubmit, setPanelExpanded, trimmedSelectedText]);
+
+  if (!style || !trimmedSelectedText) {
+    return null;
+  }
+
+  if (!expanded) {
+    return (
+      <button
+        type="button"
+        className="btn btn-primary btn-sm selection-comment-trigger"
+        style={style}
+        onMouseDown={(event) => event.preventDefault()}
+        onClick={() => setPanelExpanded(true)}
+        aria-label={t("selectionComment.addCommentAria", "Add a comment to the selected text and send it to a new task")}
+      >
+        <MessageSquarePlus size={14} />
+        {t("selectionComment.addComment", "Add comment")}
+      </button>
+    );
+  }
+
+  return (
+    <div ref={rootRef} className="card selection-comment-panel" style={style} role="dialog" aria-label={t("selectionComment.dialogAria", "Comment on selected text")}> 
+      <p className="selection-comment-title">{t("selectionComment.title", "Comment on selection")}</p>
+      <pre className="selection-comment-snippet" aria-label={t("selectionComment.selectedSnippet", "Selected snippet")}>{trimmedSelectedText}</pre>
+      <textarea
+        ref={textareaRef}
+        className="input selection-comment-textarea"
+        value={comment}
+        onChange={(event) => setComment(event.target.value)}
+        placeholder={t("selectionComment.commentPlaceholder", "Describe the task this snippet should become…")}
+        aria-label={t("selectionComment.commentAria", "Comment for the new task")}
+      />
+      <div className="selection-comment-actions">
+        <button type="button" className="btn btn-sm" onClick={handleCancel}>
+          {t("selectionComment.cancel", "Cancel")}
+        </button>
+        <button type="button" className="btn btn-primary btn-sm" onClick={handleSubmit} disabled={!comment.trim()}>
+          {t("selectionComment.sendToNewTask", "Send to new task")}
+        </button>
+      </div>
+    </div>
+  );
+}
diff --git a/packages/dashboard/app/components/__tests__/DocumentsView.test.tsx b/packages/dashboard/app/components/__tests__/DocumentsView.test.tsx
index a7817f3ee0..b10b18d6b6 100644
--- a/packages/dashboard/app/components/__tests__/DocumentsView.test.tsx
+++ b/packages/dashboard/app/components/__tests__/DocumentsView.test.tsx
@@ -26,6 +26,27 @@ const mockUseProjectMarkdownFiles = vi.mocked(useProjectMarkdownFiles);
 const mockFetchWorkspaceFileContent = vi.mocked(fetchWorkspaceFileContent);
 const mockFetchTaskDetail = vi.mocked(fetchTaskDetail);
 
+function mockSelectionRect() {
+  const rect = new DOMRect(10, 20, 80, 12);
+  Object.defineProperty(Range.prototype, "getBoundingClientRect", {
+    configurable: true,
+    value: vi.fn(() => rect),
+  });
+  Object.defineProperty(Range.prototype, "getClientRects", {
+    configurable: true,
+    value: vi.fn(() => ({ 0: rect, length: 1, item: () => rect, [Symbol.iterator]: function* () { yield rect; } }) as DOMRectList),
+  });
+}
+
+function selectNodeText(node: Node) {
+  const range = document.createRange();
+  range.selectNodeContents(node);
+  const selection = document.getSelection();
+  selection?.removeAllRanges();
+  selection?.addRange(range);
+  document.dispatchEvent(new Event("selectionchange"));
+}
+
 const mockTaskDocuments: TaskDocumentWithTask[] = [
   {
     id: "doc-1",
@@ -186,6 +207,44 @@ describe("DocumentsView", () => {
     expect(await screen.findByText(/Hello docs/)).toBeInTheDocument();
   });
 
+  it("sends selected plain project file preview text to a new task description", async () => {
+    mockSelectionRect();
+    const onSendSelectionToTask = vi.fn();
+    render(<DocumentsView addToast={addToast} onOpenDetail={onOpenDetail} onSendSelectionToTask={onSendSelectionToTask} />);
+
+    fireEvent.click(screen.getByRole("button", { name: "Open README.md" }));
+    const plainPreview = await screen.findByText(/Hello docs/);
+    selectNodeText(plainPreview);
+
+    fireEvent.click(await screen.findByRole("button", { name: /add a comment/i }));
+    fireEvent.change(screen.getByLabelText(/comment for the new task/i), { target: { value: "Create a docs task." } });
+    fireEvent.click(screen.getByRole("button", { name: /send to new task/i }));
+
+    expect(onSendSelectionToTask).toHaveBeenCalledWith(expect.stringContaining("File: README.md"));
+    expect(onSendSelectionToTask).toHaveBeenCalledWith(expect.stringContaining("Hello docs"));
+    expect(onSendSelectionToTask).toHaveBeenCalledWith(expect.stringContaining("Create a docs task."));
+  });
+
+  it("sends selected markdown project file preview text to a new task description", async () => {
+    mockSelectionRect();
+    const onSendSelectionToTask = vi.fn();
+    render(<DocumentsView addToast={addToast} onOpenDetail={onOpenDetail} onSendSelectionToTask={onSendSelectionToTask} />);
+
+    fireEvent.click(screen.getByRole("button", { name: "Open README.md" }));
+    await screen.findByText(/Hello docs/);
+    fireEvent.click(screen.getByRole("button", { name: /switch to markdown/i }));
+    const markdownPreviewText = await screen.findByText("Hello docs");
+    selectNodeText(markdownPreviewText);
+
+    fireEvent.click(await screen.findByRole("button", { name: /add a comment/i }));
+    fireEvent.change(screen.getByLabelText(/comment for the new task/i), { target: { value: "Review this rendered content." } });
+    fireEvent.click(screen.getByRole("button", { name: /send to new task/i }));
+
+    expect(onSendSelectionToTask).toHaveBeenCalledWith(expect.stringContaining("File: README.md"));
+    expect(onSendSelectionToTask).toHaveBeenCalledWith(expect.stringContaining("Hello docs"));
+    expect(onSendSelectionToTask).toHaveBeenCalledWith(expect.stringContaining("Review this rendered content."));
+  });
+
   it("search filters task documents", async () => {
     mockUseProjectMarkdownFiles.mockReturnValue({
       files: [],
diff --git a/packages/dashboard/app/components/__tests__/FileBrowserModal.test.tsx b/packages/dashboard/app/components/__tests__/FileBrowserModal.test.tsx
index bf81ecdbe2..c581d89e22 100644
--- a/packages/dashboard/app/components/__tests__/FileBrowserModal.test.tsx
+++ b/packages/dashboard/app/components/__tests__/FileBrowserModal.test.tsx
@@ -23,6 +23,27 @@ const mockUseWorkspaceFileBrowser = vi.mocked(workspaceBrowserHook.useWorkspaceF
 const mockUseWorkspaceFileEditor = vi.mocked(workspaceEditorHook.useWorkspaceFileEditor);
 const mockUseWorkspaces = vi.mocked(workspacesHook.useWorkspaces);
 
+function mockSelectionRect() {
+  const rect = new DOMRect(10, 20, 80, 12);
+  Object.defineProperty(Range.prototype, "getBoundingClientRect", {
+    configurable: true,
+    value: vi.fn(() => rect),
+  });
+  Object.defineProperty(Range.prototype, "getClientRects", {
+    configurable: true,
+    value: vi.fn(() => ({ 0: rect, length: 1, item: () => rect, [Symbol.iterator]: function* () { yield rect; } }) as DOMRectList),
+  });
+}
+
+function selectNodeText(node: Node) {
+  const range = document.createRange();
+  range.selectNodeContents(node);
+  const selection = document.getSelection();
+  selection?.removeAllRanges();
+  selection?.addRange(range);
+  document.dispatchEvent(new Event("selectionchange"));
+}
+
 describe("FileBrowserModal", () => {
   const mockOnClose = vi.fn();
   const mockOnWorkspaceChange = vi.fn();
@@ -115,6 +136,64 @@ describe("FileBrowserModal", () => {
     expect(mockUseWorkspaceFileEditor).toHaveBeenLastCalledWith("project", "file1.ts", true, undefined);
   });
 
+  it("sends selected code text from the embedded editor to a new task description", async () => {
+    mockSelectionRect();
+    const onSendSelectionToTask = vi.fn();
+    render(
+      <FileBrowserModal
+        initialWorkspace="project"
+        isOpen={true}
+        onClose={mockOnClose}
+        onSendSelectionToTask={onSendSelectionToTask}
+      />,
+    );
+
+    fireEvent.click(screen.getByText("file1.ts"));
+    await waitFor(() => expect(screen.getByLabelText("Editor for file1.ts")).toBeInTheDocument());
+    selectNodeText(document.querySelector(".cm-content") as Node);
+
+    fireEvent.click(await screen.findByRole("button", { name: /add a comment/i }));
+    fireEvent.change(screen.getByLabelText(/comment for the new task/i), { target: { value: "Investigate this file." } });
+    fireEvent.click(screen.getByRole("button", { name: /send to new task/i }));
+
+    expect(onSendSelectionToTask).toHaveBeenCalledWith(expect.stringContaining("File: file1.ts"));
+    expect(onSendSelectionToTask).toHaveBeenCalledWith(expect.stringContaining("console.log"));
+    expect(onSendSelectionToTask).toHaveBeenCalledWith(expect.stringContaining("Investigate this file."));
+  });
+
+  it("sends selected markdown preview text from the embedded editor to a new task description", async () => {
+    mockSelectionRect();
+    const onSendSelectionToTask = vi.fn();
+    mockUseWorkspaceFileEditor.mockReturnValue({
+      ...defaultEditorState,
+      content: "# Heading\n\nPreview body",
+      originalContent: "# Heading\n\nPreview body",
+    });
+
+    render(
+      <FileBrowserModal
+        initialWorkspace="project"
+        initialFile="README.md"
+        isOpen={true}
+        onClose={mockOnClose}
+        onSendSelectionToTask={onSendSelectionToTask}
+      />,
+    );
+
+    await waitFor(() => expect(screen.getAllByText("README.md").length).toBeGreaterThan(0));
+    fireEvent.click(screen.getByRole("button", { name: /toggle editor options/i }));
+    fireEvent.click(screen.getByRole("button", { name: /preview mode/i }));
+    selectNodeText(await screen.findByText("Preview body"));
+
+    fireEvent.click(await screen.findByRole("button", { name: /add a comment/i }));
+    fireEvent.change(screen.getByLabelText(/comment for the new task/i), { target: { value: "Turn preview note into work." } });
+    fireEvent.click(screen.getByRole("button", { name: /send to new task/i }));
+
+    expect(onSendSelectionToTask).toHaveBeenCalledWith(expect.stringContaining("File: README.md"));
+    expect(onSendSelectionToTask).toHaveBeenCalledWith(expect.stringContaining("Preview body"));
+    expect(onSendSelectionToTask).toHaveBeenCalledWith(expect.stringContaining("Turn preview note into work."));
+  });
+
   it("opens with an initial file selected", async () => {
     render(
       <FileBrowserModal
diff --git a/packages/dashboard/app/components/__tests__/FileEditor.test.tsx b/packages/dashboard/app/components/__tests__/FileEditor.test.tsx
index 69f4598110..25e14c02fd 100644
--- a/packages/dashboard/app/components/__tests__/FileEditor.test.tsx
+++ b/packages/dashboard/app/components/__tests__/FileEditor.test.tsx
@@ -55,6 +55,27 @@ describe("FileEditor", () => {
     }));
   };
 
+  const mockSelectionRect = () => {
+    const rect = new DOMRect(10, 20, 80, 12);
+    Object.defineProperty(Range.prototype, "getBoundingClientRect", {
+      configurable: true,
+      value: vi.fn(() => rect),
+    });
+    Object.defineProperty(Range.prototype, "getClientRects", {
+      configurable: true,
+      value: vi.fn(() => ({ 0: rect, length: 1, item: () => rect, [Symbol.iterator]: function* () { yield rect; } }) as DOMRectList),
+    });
+  };
+
+  const selectNodeText = (node: Node) => {
+    const range = document.createRange();
+    range.selectNodeContents(node);
+    const selection = document.getSelection();
+    selection?.removeAllRanges();
+    selection?.addRange(range);
+    document.dispatchEvent(new Event("selectionchange"));
+  };
+
   it("renders CodeMirror editor with file-path aria-label", () => {
     document.documentElement.dataset.theme = "dark";
     render(<FileEditor content="" onChange={vi.fn()} filePath="a.ts" />);
@@ -136,6 +157,45 @@ describe("FileEditor", () => {
     fireEvent.click(screen.getByRole("button", { name: /edit mode/i }));
     expect(document.querySelector(".cm-editor")).toBeInTheDocument();
   });
+
+  it("sends selected CodeMirror text to a new task description", async () => {
+    document.documentElement.dataset.theme = "dark";
+    mockSelectionRect();
+    const onSendSelectionToTask = vi.fn();
+    render(<FileEditor content="alpha\nbeta" onChange={vi.fn()} filePath="src/example.ts" onSendSelectionToTask={onSendSelectionToTask} />);
+
+    act(() => {
+      getEditorView().dispatch({ selection: { anchor: 0, head: 5 } });
+    });
+    const content = document.querySelector(".cm-content") as HTMLElement;
+    selectNodeText(content);
+
+    fireEvent.click(await screen.findByRole("button", { name: /add a comment/i }));
+    fireEvent.change(screen.getByLabelText(/comment for the new task/i), { target: { value: "Extract this constant." } });
+    fireEvent.click(screen.getByRole("button", { name: /send to new task/i }));
+
+    expect(onSendSelectionToTask).toHaveBeenCalledWith(expect.stringContaining("File: src/example.ts"));
+    expect(onSendSelectionToTask).toHaveBeenCalledWith(expect.stringContaining("Lines: 1"));
+    expect(onSendSelectionToTask).toHaveBeenCalledWith(expect.stringContaining("alpha"));
+    expect(onSendSelectionToTask).toHaveBeenCalledWith(expect.stringContaining("Extract this constant."));
+  });
+
+  it("sends selected markdown preview text to a new task description", async () => {
+    mockSelectionRect();
+    const onSendSelectionToTask = vi.fn();
+    render(<FileEditor content="# Hello\n\nPreview text" onChange={vi.fn()} filePath="readme.md" onSendSelectionToTask={onSendSelectionToTask} readOnly />);
+
+    const preview = document.querySelector(".file-editor-preview .markdown-body") ?? document.querySelector(".file-editor-preview");
+    selectNodeText(preview as Node);
+
+    fireEvent.click(await screen.findByRole("button", { name: /add a comment/i }));
+    fireEvent.change(screen.getByLabelText(/comment for the new task/i), { target: { value: "Document this follow-up." } });
+    fireEvent.click(screen.getByRole("button", { name: /send to new task/i }));
+
+    expect(onSendSelectionToTask).toHaveBeenCalledWith(expect.stringContaining("File: readme.md"));
+    expect(onSendSelectionToTask).toHaveBeenCalledWith(expect.stringContaining("Preview text"));
+    expect(onSendSelectionToTask).toHaveBeenCalledWith(expect.stringContaining("Document this follow-up."));
+  });
   it("line-number toggle still flips state and gutter visibility", () => {
     document.documentElement.dataset.theme = "dark";
     const onToggle = vi.fn();
diff --git a/packages/dashboard/app/components/__tests__/MemoryView.test.tsx b/packages/dashboard/app/components/__tests__/MemoryView.test.tsx
index 8724a69fe7..c67b566a8d 100644
--- a/packages/dashboard/app/components/__tests__/MemoryView.test.tsx
+++ b/packages/dashboard/app/components/__tests__/MemoryView.test.tsx
@@ -4,6 +4,10 @@ import userEvent from "@testing-library/user-event";
 import { MemoryView } from "../MemoryView";
 import { loadAllAppCssBaseOnly } from "../../test/cssFixture";
 
+const { capturedFileEditorProps } = vi.hoisted(() => ({
+  capturedFileEditorProps: [] as Array<{ filePath: string; onSendSelectionToTask?: (description: string) => void }>,
+}));
+
 const mockUseMemoryData = vi.fn();
 
 vi.mock("../../hooks/useMemoryData", () => ({
@@ -11,7 +15,10 @@ vi.mock("../../hooks/useMemoryData", () => ({
 }));
 
 vi.mock("../FileEditor", () => ({
-  FileEditor: ({ filePath }: { filePath: string }) => <div aria-label={`Editor for ${filePath}`} />,
+  FileEditor: (props: { filePath: string; onSendSelectionToTask?: (description: string) => void }) => {
+    capturedFileEditorProps.push(props);
+    return <div aria-label={`Editor for ${props.filePath}`} />;
+  },
 }));
 
 vi.mock("lucide-react", () => ({
@@ -94,6 +101,7 @@ function createMemoryData(overrides: Record<string, unknown> = {}) {
 describe("MemoryView", () => {
   beforeEach(() => {
     vi.clearAllMocks();
+    capturedFileEditorProps.length = 0;
     mockUseMemoryData.mockReturnValue(createMemoryData());
   });
 
@@ -110,6 +118,44 @@ describe("MemoryView", () => {
     expect(screen.queryByText("This memory backend is read-only. Changes cannot be saved.")).not.toBeInTheDocument();
   });
 
+  it("passes selection-to-task callback to the memory file editor", () => {
+    const onSendSelectionToTask = vi.fn();
+
+    render(<MemoryView addToast={vi.fn()} onSendSelectionToTask={onSendSelectionToTask} />);
+
+    expect(capturedFileEditorProps).toEqual(
+      expect.arrayContaining([
+        expect.objectContaining({
+          filePath: ".fusion/memory/MEMORY.md",
+          onSendSelectionToTask,
+        }),
+      ]),
+    );
+  });
+
+  it("passes selection-to-task callback to the raw insights editor", async () => {
+    const onSendSelectionToTask = vi.fn();
+    mockUseMemoryData.mockReturnValue(
+      createMemoryData({
+        insightsExists: true,
+        insightsContent: "## Patterns\n- Keep useful notes",
+      }),
+    );
+
+    render(<MemoryView addToast={vi.fn()} onSendSelectionToTask={onSendSelectionToTask} />);
+    await userEvent.click(screen.getByRole("tab", { name: "Insights" }));
+    await userEvent.click(screen.getByRole("button", { name: "Edit Raw" }));
+
+    expect(capturedFileEditorProps).toEqual(
+      expect.arrayContaining([
+        expect.objectContaining({
+          filePath: ".fusion/memory/INSIGHTS.md",
+          onSendSelectionToTask,
+        }),
+      ]),
+    );
+  });
+
   it("shows read-only warning after backend resolves as non-writable", () => {
     mockUseMemoryData.mockReturnValue(
       createMemoryData({
diff --git a/packages/dashboard/app/components/__tests__/NewTaskModal.test.tsx b/packages/dashboard/app/components/__tests__/NewTaskModal.test.tsx
index 47bf14cc4b..9622b2cc40 100644
--- a/packages/dashboard/app/components/__tests__/NewTaskModal.test.tsx
+++ b/packages/dashboard/app/components/__tests__/NewTaskModal.test.tsx
@@ -205,6 +205,23 @@ describe("NewTaskModal", () => {
     });
   });
 
+  it("seeds the description when opened with an initial description", () => {
+    renderNewTaskModal({ initialDescription: "File: README.md\n\nComment:\nFollow up" });
+
+    expect(screen.getByRole("textbox")).toHaveValue("File: README.md\n\nComment:\nFollow up");
+    expect(screen.getByRole("button", { name: "Create Task" })).not.toBeDisabled();
+  });
+
+  it("does not clobber user edits when initialDescription changes while open", () => {
+    const { rerender, props } = renderNewTaskModal({ initialDescription: "Seeded description" });
+    const descTextarea = screen.getByRole("textbox");
+
+    fireEvent.change(descTextarea, { target: { value: "User edited text" } });
+    rerender(<NewTaskModal {...props} initialDescription="Different seed" />);
+
+    expect(screen.getByRole("textbox")).toHaveValue("User edited text");
+  });
+
   it("creates task with description when submitted", async () => {
     const { props } = renderNewTaskModal();
     
diff --git a/packages/dashboard/app/components/__tests__/SelectionCommentPopover.test.tsx b/packages/dashboard/app/components/__tests__/SelectionCommentPopover.test.tsx
new file mode 100644
index 0000000000..8689e7938e
--- /dev/null
+++ b/packages/dashboard/app/components/__tests__/SelectionCommentPopover.test.tsx
@@ -0,0 +1,75 @@
+import { fireEvent, render, screen } from "@testing-library/react";
+import { describe, expect, it, vi } from "vitest";
+import { SelectionCommentPopover, composeSelectionCommentDescription } from "../SelectionCommentPopover";
+
+vi.mock("lucide-react", () => ({
+  MessageSquarePlus: () => null,
+}));
+
+describe("SelectionCommentPopover", () => {
+  it("renders a trigger for a selection and submits a composed task description", () => {
+    const onSubmit = vi.fn();
+    render(
+      <SelectionCommentPopover
+        selectedText="const answer = 42;"
+        anchorRect={new DOMRect(20, 30, 100, 16)}
+        filePath="src/example.ts"
+        lineRange={{ start: 4, end: 4 }}
+        onSubmit={onSubmit}
+      />,
+    );
+
+    fireEvent.click(screen.getByRole("button", { name: /add a comment/i }));
+    fireEvent.change(screen.getByLabelText(/comment for the new task/i), {
+      target: { value: "Turn this into a configurable value." },
+    });
+    fireEvent.click(screen.getByRole("button", { name: /send to new task/i }));
+
+    expect(onSubmit).toHaveBeenCalledWith([
+      "File: src/example.ts",
+      "Lines: 4",
+      "",
+      "Selected snippet:",
+      "```text",
+      "const answer = 42;",
+      "```",
+      "",
+      "Comment:",
+      "Turn this into a configurable value.",
+    ].join("\n"));
+  });
+
+  it("cancels cleanly without submitting", () => {
+    const onSubmit = vi.fn();
+    const onCancel = vi.fn();
+    const onOpenChange = vi.fn();
+    render(
+      <SelectionCommentPopover
+        selectedText="snippet"
+        anchorRect={new DOMRect(20, 30, 100, 16)}
+        filePath="README.md"
+        onSubmit={onSubmit}
+        onCancel={onCancel}
+        onOpenChange={onOpenChange}
+      />,
+    );
+
+    fireEvent.click(screen.getByRole("button", { name: /add a comment/i }));
+    fireEvent.change(screen.getByLabelText(/comment for the new task/i), { target: { value: "A note" } });
+    fireEvent.click(screen.getByRole("button", { name: /cancel/i }));
+
+    expect(onSubmit).not.toHaveBeenCalled();
+    expect(onCancel).toHaveBeenCalledTimes(1);
+    expect(onOpenChange).toHaveBeenCalledWith(true);
+    expect(onOpenChange).toHaveBeenLastCalledWith(false);
+    expect(screen.getByRole("button", { name: /add a comment/i })).toBeInTheDocument();
+  });
+
+  it("uses a longer markdown fence when the snippet contains backticks", () => {
+    expect(composeSelectionCommentDescription({
+      filePath: "README.md",
+      selectedText: "```js\ncode\n```",
+      comment: "Move this example.",
+    })).toContain("````text\n```js\ncode\n```\n````");
+  });
+});
diff --git a/packages/dashboard/app/hooks/__tests__/useModalManager.test.ts b/packages/dashboard/app/hooks/__tests__/useModalManager.test.ts
index e2b90a31a2..517af47b45 100644
--- a/packages/dashboard/app/hooks/__tests__/useModalManager.test.ts
+++ b/packages/dashboard/app/hooks/__tests__/useModalManager.test.ts
@@ -55,6 +55,7 @@ describe("useModalManager", () => {
     );
 
     expect(result.current.newTaskModalOpen).toBe(false);
+    expect(result.current.newTaskInitialDescription).toBeNull();
     expect(result.current.anyModalOpen).toBe(false);
 
     act(() => {
@@ -62,6 +63,7 @@ describe("useModalManager", () => {
     });
 
     expect(result.current.newTaskModalOpen).toBe(true);
+    expect(result.current.newTaskInitialDescription).toBeNull();
     expect(result.current.anyModalOpen).toBe(true);
 
     act(() => {
@@ -69,9 +71,36 @@ describe("useModalManager", () => {
     });
 
     expect(result.current.newTaskModalOpen).toBe(false);
+    expect(result.current.newTaskInitialDescription).toBeNull();
     expect(result.current.anyModalOpen).toBe(false);
   });
 
+  it("opens the new task modal with a seeded description and resets it on close", () => {
+    const { result } = renderHook(() =>
+      useModalManager({ projectId: "proj_1", planningSessions: [] }),
+    );
+
+    act(() => {
+      result.current.openNewTaskWithDescription("File: README.md\n\nComment:\nCreate a task");
+    });
+
+    expect(result.current.newTaskModalOpen).toBe(true);
+    expect(result.current.newTaskInitialDescription).toContain("README.md");
+
+    act(() => {
+      result.current.closeNewTask();
+    });
+
+    expect(result.current.newTaskModalOpen).toBe(false);
+    expect(result.current.newTaskInitialDescription).toBeNull();
+
+    act(() => {
+      result.current.openNewTask();
+    });
+
+    expect(result.current.newTaskInitialDescription).toBeNull();
+  });
+
   it("handles planning open, resume, and close lifecycle", () => {
     const { result } = renderHook(() =>
       useModalManager({ projectId: "proj_1", planningSessions: [{ id: "plan-1" }] }),
diff --git a/packages/dashboard/app/hooks/__tests__/useSelectionComment.test.ts b/packages/dashboard/app/hooks/__tests__/useSelectionComment.test.ts
new file mode 100644
index 0000000000..a534c1865b
--- /dev/null
+++ b/packages/dashboard/app/hooks/__tests__/useSelectionComment.test.ts
@@ -0,0 +1,140 @@
+import { act, renderHook, waitFor } from "@testing-library/react";
+import { createRef } from "react";
+import { beforeEach, describe, expect, it, vi } from "vitest";
+import { useSelectionComment } from "../useSelectionComment";
+
+function mockRangeRect() {
+  const rect = new DOMRect(10, 20, 80, 12);
+  Object.defineProperty(Range.prototype, "getBoundingClientRect", {
+    configurable: true,
+    value: vi.fn(() => rect),
+  });
+  Object.defineProperty(Range.prototype, "getClientRects", {
+    configurable: true,
+    value: vi.fn(() => ({ 0: rect, length: 1, item: () => rect, [Symbol.iterator]: function* () { yield rect; } }) as DOMRectList),
+  });
+}
+
+function selectText(node: Node) {
+  const range = document.createRange();
+  range.selectNodeContents(node);
+  const selection = document.getSelection();
+  selection?.removeAllRanges();
+  selection?.addRange(range);
+  document.dispatchEvent(new Event("selectionchange"));
+}
+
+describe("useSelectionComment", () => {
+  beforeEach(() => {
+    document.body.innerHTML = "";
+    vi.restoreAllMocks();
+    mockRangeRect();
+  });
+
+  it("reports selected text and anchor rect inside the container", async () => {
+    const container = document.createElement("div");
+    const text = document.createTextNode("selected snippet");
+    container.append(text);
+    document.body.append(container);
+    const ref = createRef<HTMLElement>();
+    ref.current = container;
+
+    const { result } = renderHook(() => useSelectionComment(ref));
+
+    act(() => selectText(text));
+
+    await waitFor(() => expect(result.current?.selectedText).toBe("selected snippet"));
+    expect(result.current?.anchorRect.left).toBe(10);
+  });
+
+  it("clears selection state when the selection is outside the container", async () => {
+    const container = document.createElement("div");
+    container.textContent = "inside";
+    const outside = document.createElement("div");
+    outside.textContent = "outside";
+    document.body.append(container, outside);
+    const ref = createRef<HTMLElement>();
+    ref.current = container;
+
+    const { result } = renderHook(() => useSelectionComment(ref));
+
+    act(() => selectText(outside.firstChild as Node));
+
+    await waitFor(() => expect(result.current).toBeNull());
+  });
+
+  it("clears selection state when the selection is collapsed", async () => {
+    const container = document.createElement("div");
+    const text = document.createTextNode("selected snippet");
+    container.append(text);
+    document.body.append(container);
+    const ref = createRef<HTMLElement>();
+    ref.current = container;
+
+    const { result } = renderHook(() => useSelectionComment(ref));
+    act(() => selectText(text));
+    await waitFor(() => expect(result.current?.selectedText).toBe("selected snippet"));
+
+    act(() => {
+      const selection = document.getSelection();
+      selection?.collapse(text, 0);
+      document.dispatchEvent(new Event("selectionchange"));
+    });
+
+    await waitFor(() => expect(result.current).toBeNull());
+  });
+
+  it("keeps the existing selection state while locked", async () => {
+    const container = document.createElement("div");
+    const text = document.createTextNode("selected snippet");
+    container.append(text);
+    document.body.append(container);
+    const ref = createRef<HTMLElement>();
+    ref.current = container;
+
+    let locked = false;
+    const { result, rerender } = renderHook(() => useSelectionComment(ref, { locked }));
+    act(() => selectText(text));
+    await waitFor(() => expect(result.current?.selectedText).toBe("selected snippet"));
+
+    locked = true;
+    rerender();
+    act(() => {
+      const selection = document.getSelection();
+      selection?.collapse(text, 0);
+      document.dispatchEvent(new Event("selectionchange"));
+    });
+
+    expect(result.current?.selectedText).toBe("selected snippet");
+  });
+
+  it("propagates a line range from the optional mapper", async () => {
+    const container = document.createElement("div");
+    const text = document.createTextNode("selected snippet");
+    container.append(text);
+    document.body.append(container);
+    const ref = createRef<HTMLElement>();
+    ref.current = container;
+
+    const { result } = renderHook(() => useSelectionComment(ref, { getLineRange: () => ({ start: 2, end: 5 }) }));
+
+    act(() => selectText(text));
+
+    await waitFor(() => expect(result.current?.lineRange).toEqual({ start: 2, end: 5 }));
+  });
+
+  it("ignores whitespace-only selections", async () => {
+    const container = document.createElement("div");
+    const text = document.createTextNode("   ");
+    container.append(text);
+    document.body.append(container);
+    const ref = createRef<HTMLElement>();
+    ref.current = container;
+
+    const { result } = renderHook(() => useSelectionComment(ref));
+
+    act(() => selectText(text));
+
+    await waitFor(() => expect(result.current).toBeNull());
+  });
+});
diff --git a/packages/dashboard/app/hooks/useModalManager.ts b/packages/dashboard/app/hooks/useModalManager.ts
index 28a4d1f754..e4cbaf825b 100644
--- a/packages/dashboard/app/hooks/useModalManager.ts
+++ b/packages/dashboard/app/hooks/useModalManager.ts
@@ -28,6 +28,7 @@ interface UseModalManagerOptions {
 export interface ModalManager {
   // State
   newTaskModalOpen: boolean;
+  newTaskInitialDescription: string | null;
   isPlanningOpen: boolean;
   planningInitialPlan: string | null;
   planningResumeSessionId: string | undefined;
@@ -69,6 +70,7 @@ export interface ModalManager {
 
   // Handlers
   openNewTask: () => void;
+  openNewTaskWithDescription: (description: string) => void;
   closeNewTask: () => void;
 
   openPlanning: () => void;
@@ -155,6 +157,7 @@ export function useModalManager(options: UseModalManagerOptions): ModalManager {
   const { planningSessions } = options;
 
   const [newTaskModalOpen, setNewTaskModalOpen] = useState(false);
+  const [newTaskInitialDescription, setNewTaskInitialDescription] = useState<string | null>(null);
   const [isPlanningOpen, setIsPlanningOpen] = useState(false);
   const [planningInitialPlan, setPlanningInitialPlan] = useState<string | null>(null);
   const [planningResumeSessionId, setPlanningResumeSessionId] = useState<string | undefined>(undefined);
@@ -217,8 +220,18 @@ export function useModalManager(options: UseModalManagerOptions): ModalManager {
       modelOnboardingOpen,
   );
 
-  const openNewTask = useCallback(() => setNewTaskModalOpen(true), []);
-  const closeNewTask = useCallback(() => setNewTaskModalOpen(false), []);
+  const openNewTask = useCallback(() => {
+    setNewTaskInitialDescription(null);
+    setNewTaskModalOpen(true);
+  }, []);
+  const openNewTaskWithDescription = useCallback((description: string) => {
+    setNewTaskInitialDescription(description);
+    setNewTaskModalOpen(true);
+  }, []);
+  const closeNewTask = useCallback(() => {
+    setNewTaskModalOpen(false);
+    setNewTaskInitialDescription(null);
+  }, []);
 
   const openPlanning = useCallback(() => setIsPlanningOpen(true), []);
   const openPlanningWithInitialPlan = useCallback((initialPlan: string) => {
@@ -412,6 +425,7 @@ export function useModalManager(options: UseModalManagerOptions): ModalManager {
 
   return {
     newTaskModalOpen,
+    newTaskInitialDescription,
     isPlanningOpen,
     planningInitialPlan,
     planningResumeSessionId,
@@ -447,6 +461,7 @@ export function useModalManager(options: UseModalManagerOptions): ModalManager {
     modelOnboardingOpen,
     anyModalOpen,
     openNewTask,
+    openNewTaskWithDescription,
     closeNewTask,
     openPlanning,
     openPlanningWithInitialPlan,
diff --git a/packages/dashboard/app/hooks/useSelectionComment.ts b/packages/dashboard/app/hooks/useSelectionComment.ts
new file mode 100644
index 0000000000..ee617ac30e
--- /dev/null
+++ b/packages/dashboard/app/hooks/useSelectionComment.ts
@@ -0,0 +1,95 @@
+import { useCallback, useEffect, useState, type RefObject } from "react";
+
+export interface SelectionCommentLineRange {
+  start: number;
+  end: number;
+}
+
+export interface SelectionCommentState {
+  selectedText: string;
+  anchorRect: DOMRect;
+  lineRange?: SelectionCommentLineRange;
+}
+
+interface UseSelectionCommentOptions {
+  getLineRange?: (selection: Selection) => SelectionCommentLineRange | undefined;
+  locked?: boolean;
+}
+
+function isNodeInside(container: HTMLElement, node: Node | null): boolean {
+  if (!node) return false;
+  return container === node || container.contains(node);
+}
+
+function getRangeAnchorRect(range: Range): DOMRect | null {
+  const rect = range.getBoundingClientRect();
+  if (rect.width > 0 || rect.height > 0) {
+    return rect;
+  }
+  const firstRect = range.getClientRects()[0];
+  return firstRect ?? null;
+}
+
+/**
+ * FNXC:SelectionComment 2026-06-16-23:49:
+ * File content surfaces need a shared selection detector so editor, markdown preview, and read-only preview containers can offer the same comment-to-New-Task affordance without mutating the file or disrupting copy selection.
+ */
+export function useSelectionComment(
+  containerRef: RefObject<HTMLElement | null>,
+  options: UseSelectionCommentOptions = {},
+): SelectionCommentState | null {
+  const { getLineRange, locked = false } = options;
+  const [selectionState, setSelectionState] = useState<SelectionCommentState | null>(null);
+
+  const refreshSelection = useCallback(() => {
+    if (locked) {
+      return;
+    }
+
+    const container = containerRef.current;
+    const selection = document.getSelection();
+    if (!container || !selection || selection.rangeCount === 0 || selection.isCollapsed) {
+      setSelectionState(null);
+      return;
+    }
+
+    const range = selection.getRangeAt(0);
+    const selectedText = selection.toString().trim();
+    if (!selectedText) {
+      setSelectionState(null);
+      return;
+    }
+
+    if (!isNodeInside(container, range.commonAncestorContainer) || !isNodeInside(container, selection.anchorNode) || !isNodeInside(container, selection.focusNode)) {
+      setSelectionState(null);
+      return;
+    }
+
+    const anchorRect = getRangeAnchorRect(range);
+    if (!anchorRect) {
+      setSelectionState(null);
+      return;
+    }
+
+    setSelectionState({
+      selectedText,
+      anchorRect,
+      lineRange: getLineRange?.(selection),
+    });
+  }, [containerRef, getLineRange, locked]);
+
+  useEffect(() => {
+    document.addEventListener("selectionchange", refreshSelection);
+    document.addEventListener("mouseup", refreshSelection);
+    document.addEventListener("touchend", refreshSelection);
+    document.addEventListener("keyup", refreshSelection);
+    return () => {
+      document.removeEventListener("selectionchange", refreshSelection);
+      document.removeEventListener("mouseup", refreshSelection);
+      document.removeEventListener("touchend", refreshSelection);
+      document.removeEventListener("keyup", refreshSelection);
+    };
+  }, [refreshSelection]);
+
+  return selectionState;
+}
diff --git a/packages/i18n/locales/en/app.json b/packages/i18n/locales/en/app.json
index f7ef1e68db..eca22776b0 100644
--- a/packages/i18n/locales/en/app.json
+++ b/packages/i18n/locales/en/app.json
@@ -1948,6 +1948,17 @@
     "toggleWordWrap": "Toggle word wrap",
     "wrap": "Wrap"
   },
+  "selectionComment": {
+    "addComment": "Add comment",
+    "addCommentAria": "Add a comment to the selected text and send it to a new task",
+    "cancel": "Cancel",
+    "commentAria": "Comment for the new task",
+    "commentPlaceholder": "Describe the task this snippet should become…",
+    "dialogAria": "Comment on selected text",
+    "selectedSnippet": "Selected snippet",
+    "sendToNewTask": "Send to new task",
+    "title": "Comment on selection"
+  },
   "fileMention": {
     "empty": "No tasks or files found",
     "fileHeader": "Files",