feat: add planning step before visualization generation

apps/agent/main.py

@@ -18,12 +18,13 @@
 from src.query import query_data
 from src.todos import AgentState, todo_tools
 from src.form import generate_form
+from src.plan import plan_visualization
 
 load_dotenv()
 
 agent = create_deep_agent(
     model=ChatOpenAI(model=os.environ.get("LLM_MODEL", "gpt-5.4-2026-03-05")),
-    tools=[query_data, *todo_tools, generate_form],
+    tools=[query_data, plan_visualization, *todo_tools, generate_form],
     middleware=[CopilotKitMiddleware()],
     context_schema=AgentState,
     skills=[str(Path(__file__).parent / "skills")],
@@ -52,6 +53,23 @@
         - Pre-styled form elements (buttons, inputs, sliders look native automatically)
         - Pre-built SVG CSS classes for color ramps (.c-purple, .c-teal, .c-blue, etc.)
 
+        ## Visualization Workflow (MANDATORY)
+
+        When producing ANY visual response (widgetRenderer, pieChart, barChart), you MUST
+        follow this exact sequence:
+
+        1. **Acknowledge** — Reply with 1-2 sentences of plain text acknowledging the
+           request and setting context for what the visualization will show.
+        2. **Plan** — Call `plan_visualization` with your approach, technology choice,
+           and 2-4 key elements. Keep it concise.
+        3. **Build** — Call the appropriate visualization tool (widgetRenderer, pieChart,
+           or barChart).
+        4. **Narrate** — After the visualization, add 2-3 sentences walking through
+           what was built and offering to go deeper.
+
+        NEVER skip the plan_visualization step. NEVER call widgetRenderer, pieChart, or
+        barChart without calling plan_visualization first.
+
         ## Visualization Quality Standards
 
         The iframe has an import map with these ES module libraries — use `<script type="module">` and bare import specifiers:

apps/agent/src/plan.py

@@ -0,0 +1,21 @@
+"""Planning tool for visualization generation."""
+
+from langchain.tools import tool
+
+
+@tool
+def plan_visualization(
+    approach: str, technology: str, key_elements: list[str]
+) -> str:
+    """Plan a visualization before building it. MUST be called before
+    widgetRenderer, pieChart, or barChart. Outlines the approach, technology
+    choice, and key elements.
+
+    Args:
+        approach: One sentence describing the visualization strategy.
+        technology: The primary technology (e.g. "inline SVG", "Chart.js",
+            "HTML + Canvas", "Three.js", "Mermaid", "D3.js").
+        key_elements: 2-4 concise bullet points describing what will be built.
+    """
+    elements = "\n".join(f"  - {e}" for e in key_elements)
+    return f"Plan: {approach}\nTech: {technology}\n{elements}"

apps/app/src/app/page.tsx

@@ -1,27 +1,15 @@
 "use client";
 
-import { useEffect, useState } from "react";
+import { useEffect } from "react";
 import { ExampleLayout } from "@/components/example-layout";
 import { useGenerativeUIExamples, useExampleSuggestions } from "@/hooks";
 import { ExplainerCardsPortal } from "@/components/explainer-cards";
-import { DemoGallery, type DemoItem } from "@/components/demo-gallery";
-
 import { CopilotChat } from "@copilotkit/react-core/v2";
-import { useCopilotChat } from "@copilotkit/react-core";
 
 export default function HomePage() {
   useGenerativeUIExamples();
   useExampleSuggestions();
 
-  const [demoDrawerOpen, setDemoDrawerOpen] = useState(false);
-  const { appendMessage } = useCopilotChat();
-
-  const handleTryDemo = (demo: DemoItem) => {
-    setDemoDrawerOpen(false);
-    // eslint-disable-next-line @typescript-eslint/no-explicit-any
-    appendMessage({ content: demo.prompt, role: "user" } as any);
-  };
-
   // Widget bridge: handle messages from widget iframes
   useEffect(() => {
     const handler = (e: MessageEvent) => {
@@ -67,25 +55,6 @@ export default function HomePage() {
                 </p>
               </div>
               <div className="flex items-center gap-2">
-                <button
-                  onClick={() => setDemoDrawerOpen(true)}
-                  className="inline-flex items-center gap-1.5 px-3 py-2 rounded-full text-sm font-medium no-underline whitespace-nowrap transition-all duration-150 hover:-translate-y-px cursor-pointer"
-                  style={{
-                    color: "var(--text-secondary)",
-                    border: "1px solid var(--color-border-glass, rgba(0,0,0,0.1))",
-                    background: "var(--surface-primary, rgba(255,255,255,0.6))",
-                    fontFamily: "var(--font-family)",
-                  }}
-                  title="Open Demo Gallery"
-                >
-                  <svg width="15" height="15" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2" strokeLinecap="round" strokeLinejoin="round">
-                    <rect width="7" height="7" x="3" y="3" rx="1" />
-                    <rect width="7" height="7" x="14" y="3" rx="1" />
-                    <rect width="7" height="7" x="14" y="14" rx="1" />
-                    <rect width="7" height="7" x="3" y="14" rx="1" />
-                  </svg>
-                  Demos
-                </button>
                 <a
                   href="https://github.com/CopilotKit/OpenGenerativeUI"
                   target="_blank"
@@ -114,11 +83,6 @@ export default function HomePage() {
         </div>
       </div>
 
-      <DemoGallery
-        open={demoDrawerOpen}
-        onClose={() => setDemoDrawerOpen(false)}
-        onTryDemo={handleTryDemo}
-      />
     </>
   );
 }

apps/app/src/components/generative-ui/plan-card.tsx

@@ -0,0 +1,56 @@
+"use client";
+
+import { useEffect, useRef } from "react";
+
+interface PlanCardProps {
+  status: "executing" | "inProgress" | "complete";
+  approach?: string;
+  technology?: string;
+  key_elements?: string[];
+}
+
+export function PlanCard({ status, approach, technology, key_elements }: PlanCardProps) {
+  const detailsRef = useRef<HTMLDetailsElement>(null);
+  const isRunning = status === "executing" || status === "inProgress";
+
+  useEffect(() => {
+    if (!detailsRef.current) return;
+    detailsRef.current.open = isRunning;
+  }, [isRunning]);
+
+  const spinner = (
+    <span className="inline-block h-3 w-3 rounded-full border-2 border-gray-400 border-t-transparent animate-spin" />
+  );
+  const checkmark = <span className="text-green-500 text-xs">✓</span>;
+
+  return (
+    <div className="my-2 text-sm">
+      <details ref={detailsRef} open>
+        <summary className="flex items-center gap-2 text-gray-600 dark:text-gray-400 cursor-pointer list-none">
+          {isRunning ? spinner : checkmark}
+          <span className="font-medium">
+            {isRunning ? "Planning visualization…" : `Plan: ${technology || "visualization"}`}
+          </span>
+          <span className="text-[10px]">▼</span>
+        </summary>
+        {approach && (
+          <div className="pl-5 mt-1.5 space-y-1.5 text-xs text-gray-500 dark:text-zinc-400">
+            {technology && (
+              <span className="inline-block px-1.5 py-0.5 rounded bg-gray-100 dark:bg-zinc-700 text-gray-600 dark:text-zinc-300 font-medium text-[11px]">
+                {technology}
+              </span>
+            )}
+            <p className="text-gray-600 dark:text-gray-400">{approach}</p>
+            {key_elements && key_elements.length > 0 && (
+              <ul className="list-disc pl-4 space-y-0.5">
+                {key_elements.map((el, i) => (
+                  <li key={i}>{el}</li>
+                ))}
+              </ul>
+            )}
+          </div>
+        )}
+      </details>
+    </div>
+  );
+}

apps/app/src/components/generative-ui/widget-renderer.tsx

@@ -455,10 +455,17 @@ window.addEventListener('message', function(e) {
   }
 });
 
-// Auto-resize: report content height to host
+// Auto-resize: report content height to host.
+// Temporarily collapse the container so viewport-relative children (100vh, 100%)
+// don't inflate the measurement — this gives us intrinsic content height only.
 function reportHeight() {
   var content = document.getElementById('content');
-  var h = content ? content.offsetHeight : document.documentElement.scrollHeight;
+  if (!content) return;
+  content.style.height = '0';
+  content.style.overflow = 'hidden';
+  var h = content.scrollHeight;
+  content.style.height = '';
+  content.style.overflow = '';
   window.parent.postMessage({ type: 'widget-resize', height: h }, '*');
 }
 var ro = new ResizeObserver(reportHeight);
@@ -573,7 +580,7 @@ export function WidgetRenderer({ title, html }: WidgetRendererProps) {
       e.data?.type === "widget-resize" &&
       typeof e.data.height === "number"
     ) {
-      setHeight(Math.max(50, Math.min(e.data.height + 8, 4000)));
+      setHeight(Math.max(50, Math.min(e.data.height, 4000)));
     }
   }, []);
 

apps/app/src/hooks/use-example-suggestions.tsx

@@ -3,7 +3,7 @@ import { useConfigureSuggestions } from "@copilotkit/react-core/v2";
 export const useExampleSuggestions = () => {
   useConfigureSuggestions({
     suggestions: [
-      { title: "Visualize a binary search", message: "Visualize how binary search works on a sorted list. Step by step." },
+      { title: "Visualize a car axle", message: "Visualize how a car axle works" },
       { title: "3D Plane Controls", message: "Create a 3D plane in Three.js to explain how pitch, roll, and yaw work with buttons that animate on hover." },
       { title: "Cool 3D sphere", message: "Create a 3D animation of a sphere turning into an icosahedron when the mouse is on it and back to a sphere when it's not on the icosahedron, make it cool." },
     ],

apps/app/src/hooks/use-generative-ui-examples.tsx

@@ -7,6 +7,7 @@ import {
   useFrontendTool,
   useHumanInTheLoop,
   useDefaultRenderTool,
+  useRenderTool,
 } from "@copilotkit/react-core/v2";
 
 // Generative UI imports
@@ -15,6 +16,7 @@ import { BarChart, BarChartProps } from "@/components/generative-ui/charts/bar-c
 import { WidgetRenderer, WidgetRendererProps } from "@/components/generative-ui/widget-renderer";
 import { MeetingTimePicker } from "@/components/generative-ui/meeting-time-picker";
 import { ToolReasoning } from "@/components/tool-rendering";
+import { PlanCard } from "@/components/generative-ui/plan-card";
 
 export const useGenerativeUIExamples = () => {
   const { theme, setTheme } = useTheme();
@@ -61,6 +63,22 @@ export const useGenerativeUIExamples = () => {
     render: WidgetRenderer,
   });
 
+  // --------------------------
+  // 🪁 Plan Visualization: Custom rendering for the planning step
+  // --------------------------
+  const PlanVisualizationParams = z.object({
+    approach: z.string(),
+    technology: z.string(),
+    key_elements: z.array(z.string()),
+  });
+  useRenderTool({
+    name: "plan_visualization",
+    parameters: PlanVisualizationParams,
+    render: ({ status, parameters }) => (
+      <PlanCard status={status} {...parameters} />
+    ),
+  });
+
   // --------------------------
   // 🪁 Default Tool Rendering: https://docs.copilotkit.ai/langgraph/generative-ui/backend-tools
   // --------------------------