diff --git a/apps/mcp/src/widget/hooks/useApp.ts b/apps/mcp/src/widget/hooks/useApp.ts
index 2c5ff25a..816b0987 100644
--- a/apps/mcp/src/widget/hooks/useApp.ts
+++ b/apps/mcp/src/widget/hooks/useApp.ts
@@ -48,19 +48,19 @@ export function useApp() {
 			},
 
 			/** Inject a user message into the conversation. Triggers a new agent turn. */
-			sendMessage(content: string) {
-				return app.sendMessage({
-					role: "user",
-					content: [{ type: "text", text: content }],
-				})
-			},
-
-			/** Update ambient model context. Model sees on next user message. */
-			updateContext(text: string, structuredContent?: Record<string, unknown>) {
-				return app.updateModelContext({
-					content: [{ type: "text", text }],
-					structuredContent,
-				})
+			async sendMessage(content: string): Promise<ToolCallResult> {
+				try {
+					const result = await app.sendMessage({
+						role: "user",
+						content: [{ type: "text", text: content }],
+					})
+					if (result.isError) {
+						return { ok: false, error: "Host rejected the message" }
+					}
+					return { ok: true }
+				} catch (err) {
+					return { ok: false, error: String(err) }
+				}
 			},
 
 			/** Send a structured log line to the host. */
diff --git a/apps/mcp/src/widget/views/Picker.tsx b/apps/mcp/src/widget/views/Picker.tsx
index 48eae948..16cfb964 100644
--- a/apps/mcp/src/widget/views/Picker.tsx
+++ b/apps/mcp/src/widget/views/Picker.tsx
@@ -28,7 +28,7 @@ export function Picker({
 	onAdvance,
 	onError,
 }: Props) {
-	const { callTool, updateContext } = useApp()
+	const { callTool, sendMessage } = useApp()
 	const log = useLog()
 	const [pending, setPending] = useState<string | null>(null)
 	const [query, setQuery] = useState("")
@@ -55,20 +55,13 @@ export function Picker({
 			onError(result.error ?? "Failed to set active workspace")
 			return
 		}
-		try {
-			await updateContext(
-				`The user selected the Supermemory workspace "${containerTag}". Use this as the active workspace for future Supermemory actions unless the user selects another workspace.`,
-				{
-					supermemory: {
-						activeWorkspace: containerTag,
-						lastAction: "workspace-selected",
-					},
-				},
-			)
-		} catch (error) {
-			log("warning", `[picker] model context update failed: ${error}`)
-		}
 		onAdvance(result.data)
+		const notification = await sendMessage(
+			`I selected "${containerTag}" as my active Supermemory workspace. Use this workspace for future Supermemory actions until I select another one.`,
+		)
+		if (!notification.ok) {
+			log("warning", `[picker] agent notification failed: ${notification.error}`)
+		}
 	}
 
 	const count = containerTags.length
diff --git a/apps/mcp/src/widget/views/Save.tsx b/apps/mcp/src/widget/views/Save.tsx
index 2ba5c7e6..50e15813 100644
--- a/apps/mcp/src/widget/views/Save.tsx
+++ b/apps/mcp/src/widget/views/Save.tsx
@@ -27,7 +27,7 @@ export function Save({
 	onAdvance,
 	onError,
 }: Props) {
-	const { callTool, updateContext } = useApp()
+	const { callTool, sendMessage } = useApp()
 	const log = useLog()
 	const [content, setContent] = useState(prefill ?? "")
 	const [selectedTag, setSelectedTag] = useState<string | null>(
@@ -63,20 +63,15 @@ export function Save({
 			onError(result.error ?? "Failed to save memory")
 			return
 		}
-		try {
-			await updateContext(
-				`The user saved a memory to the Supermemory workspace "${selectedTag}" from the interactive widget.`,
-				{
-					supermemory: {
-						activeWorkspace: selectedTag,
-						lastAction: "memory-saved",
-					},
-				},
-			)
-		} catch (error) {
-			log("warning", `[save] model context update failed: ${error}`)
-		}
+		const memoryId =
+			result.data.view === "save-success" ? result.data.id : undefined
 		onAdvance(result.data)
+		const notification = await sendMessage(
+			`I used the Supermemory widget to save a memory to workspace "${selectedTag}"${memoryId ? ` (memory ID: ${memoryId})` : ""}. The memory is already saved; do not save it again.`,
+		)
+		if (!notification.ok) {
+			log("warning", `[save] agent notification failed: ${notification.error}`)
+		}
 	}
 
 	return (
diff --git a/apps/mcp/src/widget/views/Upload.tsx b/apps/mcp/src/widget/views/Upload.tsx
index 6b0af03c..d05921fb 100644
--- a/apps/mcp/src/widget/views/Upload.tsx
+++ b/apps/mcp/src/widget/views/Upload.tsx
@@ -30,7 +30,7 @@ function formatFileSize(bytes: number): string {
 const ACCEPT = ".txt,.pdf,.png,.jpg,.jpeg,.mp4"
 
 export function Upload({ activeTag, writableTags, onAdvance, onError }: Props) {
-	const { callTool, updateContext } = useApp()
+	const { callTool, sendMessage } = useApp()
 	const log = useLog()
 	const [file, setFile] = useState<File | null>(null)
 	const [selectedTag, setSelectedTag] = useState<string | null>(
@@ -62,21 +62,18 @@ export function Upload({ activeTag, writableTags, onAdvance, onError }: Props) {
 				onError(result.error ?? "Upload failed")
 				return
 			}
-			try {
-				await updateContext(
-					`The user uploaded "${file.name}" to the Supermemory workspace "${selectedTag}" from the interactive widget.`,
-					{
-						supermemory: {
-							activeWorkspace: selectedTag,
-							lastAction: "file-uploaded",
-							fileName: file.name,
-						},
-					},
-				)
-			} catch (error) {
-				log("warning", `[upload] model context update failed: ${error}`)
-			}
+			const documentId =
+				result.data.view === "upload-success" ? result.data.id : undefined
 			onAdvance(result.data)
+			const notification = await sendMessage(
+				`I used the Supermemory widget to upload "${file.name}" to workspace "${selectedTag}"${documentId ? ` (document ID: ${documentId})` : ""}. The file is already uploaded; do not upload it again.`,
+			)
+			if (!notification.ok) {
+				log(
+					"warning",
+					`[upload] agent notification failed: ${notification.error}`,
+				)
+			}
 		} catch (err) {
 			log("error", `[upload] threw: ${err}`)
 			onError(String(err))