diff --git a/README.md b/README.md
index 97fe5e8..e31a766 100644
--- a/README.md
+++ b/README.md
@@ -22,7 +22,7 @@ message meets a specified criterion.
 - **Automatic rules** – create rules that tag or move new messages based on AI classification.
 - **Rule ordering** – drag rules to prioritize them and optionally stop processing after a match.
 - **Context menu** – apply AI rules from the message list or the message display action button.
-- **Status icons** – toolbar icons indicate when messages are queued or being classified.
+- **Status icons** – toolbar icons show when classification is in progress and briefly display success or error states.
 - **Packaging script** – `build-xpi.ps1` builds an XPI ready for installation.
 
 ## Architecture Overview
diff --git a/background.js b/background.js
index 1463ee7..e47bf99 100644
--- a/background.js
+++ b/background.js
@@ -18,14 +18,9 @@ let aiRules = [];
 let queue = Promise.resolve();
 let queuedCount = 0;
 let processing = false;
+let iconTimer = null;
 
-function updateActionIcon() {
-    let path = "resources/img/logo32.png";
-    if (processing) {
-        path = "resources/img/status-classifying.png";
-    } else if (queuedCount > 0) {
-        path = "resources/img/status-queued.png";
-    }
+function setIcon(path) {
     if (browser.browserAction) {
         browser.browserAction.setIcon({ path });
     }
@@ -34,6 +29,20 @@ function updateActionIcon() {
     }
 }
 
+function updateActionIcon() {
+    let path = "resources/img/logo32.png";
+    if (processing || queuedCount > 0) {
+        path = "resources/img/busy.png";
+    }
+    setIcon(path);
+}
+
+function showTransientIcon(path, delay = 1500) {
+    clearTimeout(iconTimer);
+    setIcon(path);
+    iconTimer = setTimeout(updateActionIcon, delay);
+}
+
 async function sha256Hex(str) {
     const buf = await crypto.subtle.digest('SHA-256', new TextEncoder().encode(str));
     return Array.from(new Uint8Array(buf), b => b.toString(16).padStart(2, '0')).join('');
@@ -125,11 +134,12 @@ async function applyAiRules(idsInput) {
                         }
                     }
                 }
-            } catch (e) {
-                logger.aiLog("failed to apply AI rules", { level: 'error' }, e);
-            } finally {
                 processing = false;
-                updateActionIcon();
+                showTransientIcon("resources/img/done.png");
+            } catch (e) {
+                processing = false;
+                logger.aiLog("failed to apply AI rules", { level: 'error' }, e);
+                showTransientIcon("resources/img/error.png");
             }
         });
     }