diff --git a/ui/src/ui/chat/grouped-render.test.ts b/ui/src/ui/chat/grouped-render.test.ts
index aa801b79613..72115dbb524 100644
--- a/ui/src/ui/chat/grouped-render.test.ts
+++ b/ui/src/ui/chat/grouped-render.test.ts
@@ -4,7 +4,6 @@ import { html, render } from "lit";
 import { afterEach, describe, expect, it, vi } from "vitest";
 import { getSafeLocalStorage } from "../../local-storage.ts";
 import type { MessageGroup } from "../types/chat-types.ts";
-import { buildChatItems, type BuildChatItemsProps } from "./build-chat-items.ts";
 import {
   renderMessageGroup,
   resetAssistantAttachmentAvailabilityCacheForTest,
@@ -104,6 +103,44 @@ function createMessageGroup(message: unknown, role: string): MessageGroup {
   };
 }
 
+function createAssistantCanvasBlock(params: {
+  suffix: string;
+  title?: string;
+  url?: string;
+  preferredHeight?: number;
+  presentationTarget?: "assistant_message" | "tool_card";
+}) {
+  const viewId = `cv_inline_${params.suffix}`;
+  const url = params.url ?? `/__openclaw__/canvas/documents/${viewId}/index.html`;
+  const title = params.title ?? "Inline demo";
+  const preferredHeight = params.preferredHeight ?? 360;
+  return {
+    type: "canvas",
+    preview: {
+      kind: "canvas",
+      surface: "assistant_message",
+      render: "url",
+      viewId,
+      title,
+      url,
+      preferredHeight,
+    },
+    rawText: JSON.stringify({
+      kind: "canvas",
+      view: {
+        backend: "canvas",
+        id: viewId,
+        url,
+        title,
+        preferred_height: preferredHeight,
+      },
+      presentation: {
+        target: params.presentationTarget ?? "assistant_message",
+      },
+    }),
+  };
+}
+
 function renderMessageGroups(
   container: HTMLElement,
   groups: MessageGroup[],
@@ -123,24 +160,6 @@ function renderMessageGroups(
   );
 }
 
-function renderBuiltMessageGroups(
-  container: HTMLElement,
-  props: Partial<BuildChatItemsProps>,
-  opts: Partial<RenderMessageGroupOptions> = {},
-) {
-  const groups = buildChatItems({
-    sessionKey: "main",
-    messages: [],
-    toolMessages: [],
-    streamSegments: [],
-    stream: null,
-    streamStartedAt: null,
-    showToolCalls: true,
-    ...props,
-  }).filter((item) => item.kind === "group");
-  renderMessageGroups(container, groups, opts);
-}
-
 function clearDeleteConfirmSkip() {
   try {
     getSafeLocalStorage()?.removeItem("openclaw:skipDeleteConfirm");
@@ -1110,41 +1129,22 @@ describe("grouped chat rendering", () => {
   it("renders hidden assistant_message canvas results with the configured sandbox", () => {
     const container = document.createElement("div");
     const renderCanvas = (params: { embedSandboxMode?: "trusted"; suffix: string }) =>
-      renderBuiltMessageGroups(
+      renderMessageGroups(
         container,
-        {
-          showToolCalls: false,
-          messages: [
+        [
+          createMessageGroup(
             {
               id: `assistant-canvas-inline-${params.suffix}`,
               role: "assistant",
-              content: [{ type: "text", text: "Inline canvas result." }],
+              content: [
+                { type: "text", text: "Inline canvas result." },
+                createAssistantCanvasBlock({ suffix: params.suffix }),
+              ],
               timestamp: Date.now(),
             },
-          ],
-          toolMessages: [
-            {
-              id: `tool-artifact-inline-${params.suffix}`,
-              role: "tool",
-              toolCallId: `call-artifact-inline-${params.suffix}`,
-              toolName: "canvas_render",
-              content: JSON.stringify({
-                kind: "canvas",
-                view: {
-                  backend: "canvas",
-                  id: `cv_inline_${params.suffix}`,
-                  url: `/__openclaw__/canvas/documents/cv_inline_${params.suffix}/index.html`,
-                  title: "Inline demo",
-                  preferred_height: 360,
-                },
-                presentation: {
-                  target: "assistant_message",
-                },
-              }),
-              timestamp: Date.now() + 1,
-            },
-          ],
-        },
+            "assistant",
+          ),
+        ],
         {
           embedSandboxMode: params.embedSandboxMode ?? "scripts",
         },
@@ -1169,19 +1169,22 @@ describe("grouped chat rendering", () => {
 
   it("renders assistant_message canvas results in the assistant bubble even when tool rows are visible", () => {
     const container = document.createElement("div");
-    renderBuiltMessageGroups(
+    renderMessageGroups(
       container,
-      {
-        showToolCalls: true,
-        messages: [
+      [
+        createMessageGroup(
           {
             id: "assistant-canvas-inline-visible",
             role: "assistant",
-            content: [{ type: "text", text: "Inline canvas result." }],
+            content: [
+              { type: "text", text: "Inline canvas result." },
+              createAssistantCanvasBlock({ suffix: "visible" }),
+            ],
             timestamp: Date.now(),
           },
-        ],
-        toolMessages: [
+          "assistant",
+        ),
+        createMessageGroup(
           {
             id: "tool-artifact-inline-visible",
             role: "tool",
@@ -1202,8 +1205,9 @@ describe("grouped chat rendering", () => {
             }),
             timestamp: Date.now() + 1,
           },
-        ],
-      },
+          "tool",
+        ),
+      ],
       {
         isToolMessageExpanded: () => true,
       },
@@ -1222,19 +1226,19 @@ describe("grouped chat rendering", () => {
   it("opens generic tool details instead of a canvas preview from tool rows", () => {
     const container = document.createElement("div");
     const onOpenSidebar = vi.fn();
-    renderBuiltMessageGroups(
+    renderMessageGroups(
       container,
-      {
-        showToolCalls: true,
-        messages: [
+      [
+        createMessageGroup(
           {
             id: "assistant-canvas-sidebar",
             role: "assistant",
             content: [{ type: "text", text: "Sidebar canvas result." }],
             timestamp: Date.now(),
           },
-        ],
-        toolMessages: [
+          "assistant",
+        ),
+        createMessageGroup(
           {
             id: "tool-artifact-sidebar",
             role: "tool",
@@ -1255,8 +1259,9 @@ describe("grouped chat rendering", () => {
             }),
             timestamp: Date.now() + 1,
           },
-        ],
-      },
+          "tool",
+        ),
+      ],
       {
         isToolExpanded: () => true,
         isToolMessageExpanded: () => true,