diff --git a/.changeset/fix-agent-cancel.md b/.changeset/fix-agent-cancel.md
new file mode 100644
index 00000000000..a100fb297a0
--- /dev/null
+++ b/.changeset/fix-agent-cancel.md
@@ -0,0 +1,5 @@
+---
+"kilo-code": patch
+---
+
+Fix blank messages and UI not updating when canceling a task in Agent Manager
diff --git a/src/core/kilocode/agent-manager/AgentManagerProvider.ts b/src/core/kilocode/agent-manager/AgentManagerProvider.ts
index ee57c2b088c..93d0bc4825c 100644
--- a/src/core/kilocode/agent-manager/AgentManagerProvider.ts
+++ b/src/core/kilocode/agent-manager/AgentManagerProvider.ts
@@ -1550,6 +1550,7 @@ export class AgentManagerProvider implements vscode.Disposable {
 		try {
 			await this.safeWriteToStdin(sessionId, message, "cancel")
 			this.log(sessionId, "Cancel request sent via stdin")
+			this.stopAgentSession(sessionId)
 		} catch (error) {
 			// Fallback to SIGTERM if stdin write fails
 			this.outputChannel.appendLine(`Failed to send cancel via stdin, falling back to SIGTERM: ${error}`)