diff --git a/src/renderer/src/assets/main.css b/src/renderer/src/assets/main.css
index c5450cdd7..c1bc72aaa 100644
--- a/src/renderer/src/assets/main.css
+++ b/src/renderer/src/assets/main.css
@@ -1426,6 +1426,29 @@
   opacity: 0.42;
 }
 
+/* Why: while a card drag previews the board, pulse the toolbar trigger with the
+   same ring the drawer uses so it reads as another way to open the board. */
+@keyframes workspace-board-trigger-preview-pulse {
+  0% {
+    box-shadow: 0 0 0 0 color-mix(in srgb, var(--sidebar-ring) 55%, transparent);
+  }
+
+  70%,
+  100% {
+    box-shadow: 0 0 0 5px color-mix(in srgb, var(--sidebar-ring) 0%, transparent);
+  }
+}
+
+[data-workspace-board-trigger][data-workspace-board-preview='true'] {
+  animation: workspace-board-trigger-preview-pulse 1.4s ease-out infinite;
+}
+
+@media (prefers-reduced-motion: reduce) {
+  [data-workspace-board-trigger][data-workspace-board-preview='true'] {
+    animation: none;
+  }
+}
+
 @keyframes workspace-kanban-sheet-in {
   from {
     clip-path: inset(0 100% 0 0);
diff --git a/src/renderer/src/components/sidebar/SidebarToolbar.tsx b/src/renderer/src/components/sidebar/SidebarToolbar.tsx
index fff9177bc..9ea74af8d 100644
--- a/src/renderer/src/components/sidebar/SidebarToolbar.tsx
+++ b/src/renderer/src/components/sidebar/SidebarToolbar.tsx
@@ -13,11 +13,13 @@ const WORKSPACE_BOARD_MOVED_HINT_DURATION_MS = 12000
 
 type SidebarToolbarProps = {
   workspaceBoardOpen: boolean
+  workspaceBoardDragPreviewOpen?: boolean
   onWorkspaceBoardToggle: () => void
 }
 
 const SidebarToolbar = React.memo(function SidebarToolbar({
   workspaceBoardOpen,
+  workspaceBoardDragPreviewOpen = false,
   onWorkspaceBoardToggle
 }: SidebarToolbarProps) {
   const [workspaceBoardMovedHintOpen, setWorkspaceBoardMovedHintOpen] = React.useState(false)
@@ -69,7 +71,11 @@ const SidebarToolbar = React.memo(function SidebarToolbar({
           <Tooltip open={workspaceBoardMovedHintOpen ? true : undefined}>
             <TooltipTrigger asChild>
               <Button
-                variant={workspaceBoardOpen ? 'secondary' : 'ghost'}
+                // Why: previewing the board from a card drag lights up the
+                // trigger so it's clear the drag is another way to open it.
+                variant={
+                  workspaceBoardOpen || workspaceBoardDragPreviewOpen ? 'secondary' : 'ghost'
+                }
                 size="icon-xs"
                 type="button"
                 aria-label={translate(
@@ -78,6 +84,7 @@ const SidebarToolbar = React.memo(function SidebarToolbar({
                 )}
                 aria-pressed={workspaceBoardOpen}
                 data-workspace-board-trigger=""
+                data-workspace-board-preview={workspaceBoardDragPreviewOpen ? 'true' : undefined}
                 onClick={handleWorkspaceBoardClick}
                 className="text-muted-foreground"
               >
diff --git a/src/renderer/src/components/sidebar/WorktreeList.tsx b/src/renderer/src/components/sidebar/WorktreeList.tsx
index c4978c19f..93ad04256 100644
--- a/src/renderer/src/components/sidebar/WorktreeList.tsx
+++ b/src/renderer/src/components/sidebar/WorktreeList.tsx
@@ -159,7 +159,6 @@ import {
   setSidebarPointerDragDocumentStyles,
   updateSidebarDragPreviewPosition
 } from './worktree-sidebar-pointer-drag-dom'
-import { shouldStartWorkspaceBoardDragPreview } from './workspace-board-drag-preview-intent'
 import {
   getWorktreeSidebarDragAutoscroll,
   getWorktreeSidebarDragRectsForGroup,
@@ -2180,24 +2179,16 @@ const VirtualizedWorktreeViewport = React.memo(function VirtualizedWorktreeViewp
       clearWorktreeDrag()
       return
     }
-    const previewSidebarContainer = scrollRef.current
+    // Why: reveal the companion board preview the moment a card drag begins so the
+    // user sees the drop target on the right and can choose whether to aim for it,
+    // rather than discovering it only after dragging into the sidebar edge.
     if (
       !drag.workspaceBoardDragPreviewRequested &&
       !workspaceBoardOpen &&
-      previewSidebarContainer
+      !hasWorkspaceKanbanSidebarDropBoard()
     ) {
-      const sidebarRect = previewSidebarContainer.getBoundingClientRect()
-      if (
-        shouldStartWorkspaceBoardDragPreview({
-          pointerX: drag.currentX,
-          startX: drag.startX,
-          sidebarRight: sidebarRect.right
-        }) &&
-        !hasWorkspaceKanbanSidebarDropBoard()
-      ) {
-        drag.workspaceBoardDragPreviewRequested = true
-        onWorkspaceBoardDragPreviewStart()
-      }
+      drag.workspaceBoardDragPreviewRequested = true
+      onWorkspaceBoardDragPreviewStart()
     }
     const boardTarget = updateWorkspaceKanbanSidebarDropTargetVisual({
       x: drag.currentX,
diff --git a/src/renderer/src/components/sidebar/index.tsx b/src/renderer/src/components/sidebar/index.tsx
index ff6ebda13..fd6801d27 100644
--- a/src/renderer/src/components/sidebar/index.tsx
+++ b/src/renderer/src/components/sidebar/index.tsx
@@ -153,6 +153,7 @@ function Sidebar({
             {/* Fixed bottom toolbar */}
             <SidebarToolbar
               workspaceBoardOpen={workspaceBoardOpen}
+              workspaceBoardDragPreviewOpen={workspaceBoardDragPreviewOpen}
               onWorkspaceBoardToggle={toggleWorkspaceBoard}
             />
           </>
diff --git a/src/renderer/src/components/sidebar/workspace-board-drag-preview-intent.test.ts b/src/renderer/src/components/sidebar/workspace-board-drag-preview-intent.test.ts
deleted file mode 100644
index 9299240ce..000000000
--- a/src/renderer/src/components/sidebar/workspace-board-drag-preview-intent.test.ts
+++ /dev/null
@@ -1,34 +0,0 @@
-import { describe, expect, it } from 'vitest'
-import { shouldStartWorkspaceBoardDragPreview } from './workspace-board-drag-preview-intent'
-
-describe('workspace board drag preview intent', () => {
-  it('does not start the expensive board preview for small sidebar reorder drags', () => {
-    expect(
-      shouldStartWorkspaceBoardDragPreview({
-        pointerX: 132,
-        startX: 96,
-        sidebarRight: 285
-      })
-    ).toBe(false)
-  })
-
-  it('starts the board preview after a rightward drag reaches the sidebar edge zone', () => {
-    expect(
-      shouldStartWorkspaceBoardDragPreview({
-        pointerX: 252,
-        startX: 96,
-        sidebarRight: 285
-      })
-    ).toBe(true)
-  })
-
-  it('ignores edge-zone drags that did not move right enough to signal board intent', () => {
-    expect(
-      shouldStartWorkspaceBoardDragPreview({
-        pointerX: 252,
-        startX: 242,
-        sidebarRight: 285
-      })
-    ).toBe(false)
-  })
-})
diff --git a/src/renderer/src/components/sidebar/workspace-board-drag-preview-intent.ts b/src/renderer/src/components/sidebar/workspace-board-drag-preview-intent.ts
deleted file mode 100644
index 1494b95bc..000000000
--- a/src/renderer/src/components/sidebar/workspace-board-drag-preview-intent.ts
+++ /dev/null
@@ -1,13 +0,0 @@
-const WORKSPACE_BOARD_DRAG_PREVIEW_EDGE_ZONE_PX = 48
-const WORKSPACE_BOARD_DRAG_PREVIEW_MIN_RIGHTWARD_PX = 16
-
-export function shouldStartWorkspaceBoardDragPreview(args: {
-  pointerX: number
-  startX: number
-  sidebarRight: number
-}): boolean {
-  return (
-    args.pointerX >= args.sidebarRight - WORKSPACE_BOARD_DRAG_PREVIEW_EDGE_ZONE_PX &&
-    args.pointerX - args.startX >= WORKSPACE_BOARD_DRAG_PREVIEW_MIN_RIGHTWARD_PX
-  )
-}