diff --git a/components/apps/calendar.tsx b/components/apps/calendar.tsx
index 136b655..d5519b3 100644
--- a/components/apps/calendar.tsx
+++ b/components/apps/calendar.tsx
@@ -260,6 +260,13 @@ Keep each section brief (1-2 sentences max). Be helpful and conversational.`,
         }),
       })
 
+      if (!response.ok) {
+        const errorBody = await response.json().catch(() => null)
+        throw new Error(
+          errorBody?.message || errorBody?.error || `Request failed (${response.status})`,
+        )
+      }
+
       const { text } = await response.json()
       setChatHistory((prev) => [...prev, { role: "assistant", content: text, isStructured: true }])
 
@@ -283,7 +290,10 @@ Keep each section brief (1-2 sentences max). Be helpful and conversational.`,
         ...prev,
         {
           role: "assistant",
-          content: "I encountered an error processing your request. Please try again.",
+          content:
+            error instanceof Error
+              ? error.message
+              : "I encountered an error processing your request. Please try again.",
           isStructured: false,
         },
       ])
diff --git a/components/apps/notes.tsx b/components/apps/notes.tsx
index e34f9e4..624f29b 100644
--- a/components/apps/notes.tsx
+++ b/components/apps/notes.tsx
@@ -59,6 +59,7 @@ export function Notes() {
   const [searchQuery, setSearchQuery] = useState("")
   const [isAnalyzing, setIsAnalyzing] = useState(false)
   const [analyzingNoteId, setAnalyzingNoteId] = useState<number | null>(null)
+  const [aiError, setAiError] = useState<string | null>(null)
 
   const currentNote = notes.find((n) => n.id === selectedNote)
 
@@ -97,6 +98,7 @@ export function Notes() {
 
     setIsAnalyzing(true)
     setAnalyzingNoteId(noteId)
+    setAiError(null)
     setIsProcessing(true)
     setCurrentThinking(`Analyzing "${note.title}"...`)
 
@@ -121,6 +123,13 @@ Respond with a JSON object (no markdown):
         }),
       })
 
+      if (!response.ok) {
+        const errorBody = await response.json().catch(() => null)
+        throw new Error(
+          errorBody?.message || errorBody?.error || `Request failed (${response.status})`,
+        )
+      }
+
       const { text } = await response.json()
 
       // Parse the AI response
@@ -148,8 +157,10 @@ Respond with a JSON object (no markdown):
       } catch {
         // Silently handle parse errors - AI response format may vary
       }
-    } catch {
-      // Silently handle categorization errors
+    } catch (error) {
+      setAiError(
+        error instanceof Error ? error.message : "Categorization failed. Please try again.",
+      )
     } finally {
       setIsAnalyzing(false)
       setAnalyzingNoteId(null)
@@ -357,6 +368,14 @@ Respond with a JSON object (no markdown):
               </div>
             )}
 
+            {aiError && (
+              <div className="px-8 pb-4">
+                <p className="text-sm text-destructive bg-destructive/10 p-3 rounded-lg">
+                  <span className="font-medium">Categorization failed:</span> {aiError}
+                </p>
+              </div>
+            )}
+
             <div className="flex-1 px-8 pb-8 overflow-auto">
               <textarea
                 className="w-full h-full resize-none focus:outline-none text-notes-foreground bg-transparent text-lg leading-relaxed"
diff --git a/components/apps/terminal.tsx b/components/apps/terminal.tsx
index 0518dfc..302f7e1 100644
--- a/components/apps/terminal.tsx
+++ b/components/apps/terminal.tsx
@@ -444,6 +444,13 @@ OUTPUT: [simulated output]`,
         }),
       })
 
+      if (!response.ok) {
+        const errorBody = await response.json().catch(() => null)
+        throw new Error(
+          errorBody?.message || errorBody?.error || `Request failed (${response.status})`,
+        )
+      }
+
       const { text } = await response.json()
 
       setHistory((prev) => {
@@ -465,7 +472,12 @@ OUTPUT: [simulated output]`,
         const filtered = prev.filter((h) => h.type !== "thinking")
         return [
           ...filtered,
-          { type: "output", content: "Agent error: Unable to analyze command. Falling back to direct execution." },
+          {
+            type: "output",
+            content: `Agent error: ${
+              error instanceof Error ? error.message : "Unable to analyze command."
+            } Falling back to direct execution.`,
+          },
         ]
       })