diff --git a/ui-electrobun/src/mainview/App.svelte b/ui-electrobun/src/mainview/App.svelte
index a1a6c6f..4147e94 100644
--- a/ui-electrobun/src/mainview/App.svelte
+++ b/ui-electrobun/src/mainview/App.svelte
@@ -9,6 +9,7 @@
   import SearchOverlay from "./SearchOverlay.svelte";
   import SplashScreen from "./SplashScreen.svelte";
   import ProjectWizard from "./ProjectWizard.svelte";
+  import GroupStatusDots from "./GroupStatusDots.svelte";
   import { themeStore } from "./theme-store.svelte.ts";
   import { fontStore } from "./font-store.svelte.ts";
   import { keybindingStore } from "./keybinding-store.svelte.ts";
@@ -381,10 +382,11 @@
           aria-label="{group.name} (Ctrl+{i + 1})"
           title="{group.name} (Ctrl+{i + 1})"
         >
-          <span class="group-circle" aria-hidden="true">{i + 1}</span>
-          {#if group.hasNew}
-            <span class="group-badge" aria-label="New activity"></span>
-          {/if}
+          <GroupStatusDots
+            projects={group.projects ?? []}
+            groupNumber={i + 1}
+            isActive={getActiveGroupId() === group.id}
+          />
         </button>
       {/each}
 
diff --git a/ui-electrobun/src/mainview/GroupStatusDots.svelte b/ui-electrobun/src/mainview/GroupStatusDots.svelte
new file mode 100644
index 0000000..cdc1d9d
--- /dev/null
+++ b/ui-electrobun/src/mainview/GroupStatusDots.svelte
@@ -0,0 +1,62 @@
+<script lang="ts">
+  import { getProjectAgentStatus } from './project-status';
+  import { statusToColor } from './status-colors';
+
+  interface Props {
+    projects: Array<{ id: string }>;
+    groupNumber: number;
+    isActive: boolean;
+    size?: number;
+  }
+
+  let { projects, groupNumber, isActive, size = 32 }: Props = $props();
+
+  function dotColor(projectId: string): string {
+    return statusToColor(getProjectAgentStatus(projectId));
+  }
+</script>
+
+<svg
+  viewBox="0 0 32 32"
+  class="group-dots"
+  width={size}
+  height={size}
+  role="img"
+  aria-label="Group {groupNumber} with {projects.length} projects"
+>
+  <!-- Border circle -->
+  <circle
+    cx="16"
+    cy="16"
+    r="15"
+    fill="none"
+    stroke={isActive ? 'var(--accent, var(--ctp-blue))' : 'var(--ctp-surface1)'}
+    stroke-width="1"
+  />
+
+  <!-- Number text -->
+  <text
+    x="16"
+    y="16"
+    text-anchor="middle"
+    dominant-baseline="central"
+    font-size="11"
+    font-weight="700"
+    fill={isActive ? 'var(--ctp-text)' : 'var(--ctp-subtext0)'}
+  >{groupNumber}</text>
+
+  <!-- Status dots -->
+  {#each projects as project, i}
+    {@const angle = (i / projects.length) * Math.PI * 2 - Math.PI / 2}
+    {@const cx = 16 + 12 * Math.cos(angle)}
+    {@const cy = 16 + 12 * Math.sin(angle)}
+    <circle cx={cx} cy={cy} r="2.5" fill={dotColor(project.id)} />
+  {/each}
+</svg>
+
+<style>
+  .group-dots {
+    display: block;
+    flex-shrink: 0;
+  }
+</style>
diff --git a/ui-electrobun/src/mainview/project-status.ts b/ui-electrobun/src/mainview/project-status.ts
new file mode 100644
index 0000000..76d4da8
--- /dev/null
+++ b/ui-electrobun/src/mainview/project-status.ts
@@ -0,0 +1,24 @@
+/**
+ * Reads agent status for a project from the global agent store.
+ * Returns a ProjectStatus suitable for status dot coloring.
+ *
+ * Reading getSession() touches the _v version counter inside agent-store,
+ * so Svelte 5 will re-evaluate any reactive context that calls this function
+ * when sessions change.
+ */
+
+import { getSession } from './agent-store.svelte';
+import type { ProjectStatus } from './status-colors';
+
+export function getProjectAgentStatus(projectId: string): ProjectStatus {
+  const session = getSession(projectId);
+  if (!session) return 'inactive';
+
+  switch (session.status) {
+    case 'running': return 'running';
+    case 'done':    return 'done';
+    case 'error':   return 'error';
+    case 'idle':    return 'inactive';
+    default:        return 'inactive';
+  }
+}
diff --git a/ui-electrobun/src/mainview/status-colors.ts b/ui-electrobun/src/mainview/status-colors.ts
new file mode 100644
index 0000000..062e833
--- /dev/null
+++ b/ui-electrobun/src/mainview/status-colors.ts
@@ -0,0 +1,14 @@
+/**
+ * Pure function mapping project status to a CSS custom property color.
+ */
+
+export type ProjectStatus = 'inactive' | 'running' | 'done' | 'error';
+
+export function statusToColor(status: ProjectStatus): string {
+  switch (status) {
+    case 'running': return 'var(--ctp-green)';
+    case 'done':    return 'var(--ctp-peach)';
+    case 'error':   return 'var(--ctp-red)';
+    default:        return 'var(--ctp-overlay0)';
+  }
+}