diff --git a/internal/gateway/methods/chat.go b/internal/gateway/methods/chat.go
index 6cda9c1d..7c0bab22 100644
--- a/internal/gateway/methods/chat.go
+++ b/internal/gateway/methods/chat.go
@@ -122,8 +122,11 @@ func (m *ChatMethods) handleSend(ctx context.Context, client *gateway.Client, re
 		sessionKey = sessions.SessionKey(params.AgentID, "ws-"+client.ID())
 	}
 
-	// Inject user_id into context for downstream stores/tools
-	runCtxBase := ctx
+	// Detach from HTTP request context so agent runs survive page navigation/reconnect.
+	// WithoutCancel preserves all context values (locale, user ID, etc.)
+	// but HTTP request cancellation no longer propagates.
+	// Explicit abort via chat.abort still works through the per-run cancel().
+	runCtxBase := context.WithoutCancel(ctx)
 	if userID != "" {
 		runCtxBase = store.WithUserID(runCtxBase, userID)
 	}