From c4cc764f8e693f8b6dbc29e2833b2cff68e79554 Mon Sep 17 00:00:00 2001
From: zahlekhan <zahle@thesys.dev>
Date: Thu, 30 Jul 2026 18:51:42 +0530
Subject: [PATCH 1/5] feat(docs): track demo agent interactions

---
 docs/README.md                                |  29 +++
 docs/app/api/chat/route.ts                    |   3 +-
 .../agent-surfaces/cloud-agent-surface.tsx    |  10 +
 .../agent-surfaces/oss-agent-surface.tsx      |  11 +
 .../agent-surfaces/cloud-agent-surface.tsx    |   5 +
 .../agent-surfaces/oss-agent-surface.tsx      |   5 +
 .../_components/compare-page-client.tsx       |  10 +-
 .../_components/comparison-analytics.test.ts  |  63 +++++
 .../_components/comparison-analytics.ts       |  31 +++
 .../_components/comparison-controls.tsx       |  14 +-
 docs/app/demo/github/constants.ts             |   2 +-
 docs/app/demo/github/page.tsx                 |  30 ++-
 docs/app/demos/constants.ts                   |   8 +-
 docs/app/demos/page.tsx                       |   7 +
 docs/lib/demo-analytics.test.ts               | 216 ++++++++++++++++++
 docs/lib/demo-analytics.ts                    |  87 +++++++
 docs/lib/demo-models.ts                       |  16 ++
 docs/lib/thesys-link-attribution.test.ts      |  53 +++++
 docs/package.json                             |   4 +-
 docs/plans/frontend-posthog-demo-analytics.md | 185 +++++++++++++++
 packages/react-headless/src/index.ts          |   3 +
 .../react-headless/src/store/ChatProvider.tsx |   4 +-
 .../store/__tests__/__helpers/makeStore.ts    |   7 +-
 .../store/__tests__/createChatStore.test.ts   |  43 ++++
 .../src/store/createChatStore.ts              |  13 +-
 packages/react-headless/src/store/types.ts    |  20 +-
 .../AgentInterface/AgentInterface.tsx         |   2 +
 .../AgentInterface/ConversationStarter.tsx    |  11 +-
 .../src/components/AgentInterface/README.md   |  17 +-
 .../AgentInterface/components/Composer.tsx    |  11 +-
 .../components/DesktopWelcomeComposer.tsx     |  11 +-
 .../OpenUIChat/CustomComposerAdapter.tsx      |   2 +-
 .../OpenUIChat/GenUIAssistantMessage.tsx      |  11 +-
 .../OpenUIChat/withChatProvider.tsx           |   2 +
 pnpm-lock.yaml                                |   3 +
 35 files changed, 892 insertions(+), 57 deletions(-)
 create mode 100644 docs/app/compare/_components/comparison-analytics.test.ts
 create mode 100644 docs/app/compare/_components/comparison-analytics.ts
 create mode 100644 docs/lib/demo-analytics.test.ts
 create mode 100644 docs/lib/demo-analytics.ts
 create mode 100644 docs/lib/demo-models.ts
 create mode 100644 docs/lib/thesys-link-attribution.test.ts
 create mode 100644 docs/plans/frontend-posthog-demo-analytics.md

diff --git a/docs/README.md b/docs/README.md
index 332d32d37..470bb0057 100644
--- a/docs/README.md
+++ b/docs/README.md
@@ -45,6 +45,35 @@ a shared, cross-instance session-and-IP rate limiter, Cloud organization budgets
 an approved conversation retention/deletion process are in place. Same-origin validation is an
 additional browser safeguard, not a substitute for those cost controls.
 
+### Demo interaction analytics
+
+The four hosted demos (`/compare`, `/demo/github`, `/chat`, and `/demos`) emit
+`demo_agent_interaction` PostHog events for accepted user interactions. Most turns emit one event;
+`/compare` emits one per visible panel. The instrumentation supplies only these custom dimensions
+(PostHog may also attach its standard page context):
+
+- `demo`: the stable demo identifier
+- `variant`: the visible comparison mode or chat mode when applicable
+- `model`: the canonical provider/model ID requested for the interaction
+- `interaction_source`: `composer`, `starter`, or `rendered_action`
+
+`/compare` emits two events for a shared prompt, one per available mode in the selected visible
+pair. Its hidden third controller still receives the prompt in the background, but that work is
+not counted as a visible user interaction. A generated `continue_conversation` action emits one
+event for the panel it targets. Prefill-only chips, blocked submissions, restored messages, and
+local generated-UI state changes do not emit events.
+
+Demo analytics never add prompt or message content, generated output, action payloads, form state,
+GitHub usernames, action or tool URLs, thread or Cloud user IDs, tool arguments, or raw errors. The
+docs site uses the shared, fail-open PostHog client in `lib/analytics.ts`; published OpenUI packages
+do not initialize or send analytics.
+
+OpenUI visitors remain anonymous. Outbound `thesys.dev` links carry PostHog's current anonymous
+distinct ID and session ID as handoff query parameters, not event properties. The receiving console
+validates and removes those parameters before analytics initialization, bootstraps the distinct ID
+as anonymous, and later merges the demo history through its canonical `posthog.identify(user.id)`
+call. Both applications must use the same PostHog project, and the console resets PostHog on logout.
+
 ## Project structure
 
 ```
diff --git a/docs/app/api/chat/route.ts b/docs/app/api/chat/route.ts
index e49212f6e..2528e9ef7 100644
--- a/docs/app/api/chat/route.ts
+++ b/docs/app/api/chat/route.ts
@@ -1,3 +1,4 @@
+import { DEFAULT_MODEL } from "@/lib/openui-cloud/models";
 import { readFileSync } from "fs";
 import { NextRequest } from "next/server";
 import OpenAI from "openai";
@@ -293,7 +294,7 @@ export async function POST(req: NextRequest) {
     apiKey,
     baseURL: "https://openrouter.ai/api/v1",
   });
-  const MODEL = "openai/gpt-5.4";
+  const MODEL = DEFAULT_MODEL;
 
   const cleanMessages = (messages as any[])
     .filter(
diff --git a/docs/app/chat/_components/agent-surfaces/cloud-agent-surface.tsx b/docs/app/chat/_components/agent-surfaces/cloud-agent-surface.tsx
index 16125deb7..9574c4e70 100644
--- a/docs/app/chat/_components/agent-surfaces/cloud-agent-surface.tsx
+++ b/docs/app/chat/_components/agent-surfaces/cloud-agent-surface.tsx
@@ -1,5 +1,6 @@
 "use client";
 
+import { captureDemoAgentInteraction } from "@/lib/demo-analytics";
 import { createCloudChatLLM } from "@/lib/openui-cloud/chat-llm";
 import { DEFAULT_MODEL } from "@/lib/openui-cloud/models";
 import { CLOUD_USER_ID_HEADER, getOrCreateCloudUserId } from "@/lib/openui-cloud/user-id";
@@ -82,6 +83,15 @@ export function CloudAgentSurface() {
         scrollOnLoad={false}
         starterVariant="short"
         starters={CLOUD_STARTERS}
+        onUserMessageAccepted={({ source }) => {
+          if (source === "programmatic") return;
+          captureDemoAgentInteraction({
+            demo: "openui_chat",
+            variant: "cloud",
+            model: selectedModel,
+            interaction_source: source,
+          });
+        }}
       >
         <AgentInterface.MobileHeader
           className={styles.cloudMobileHeader}
diff --git a/docs/app/chat/_components/agent-surfaces/oss-agent-surface.tsx b/docs/app/chat/_components/agent-surfaces/oss-agent-surface.tsx
index 0ad98166d..f35b45b82 100644
--- a/docs/app/chat/_components/agent-surfaces/oss-agent-surface.tsx
+++ b/docs/app/chat/_components/agent-surfaces/oss-agent-surface.tsx
@@ -1,6 +1,8 @@
 "use client";
 
+import { captureDemoAgentInteraction } from "@/lib/demo-analytics";
 import { isDemoCreditsErrorPayload } from "@/lib/demo-credits";
+import { DEFAULT_MODEL } from "@/lib/openui-cloud/models";
 import {
   AgentInterface,
   openAIAdapter,
@@ -80,6 +82,15 @@ export function OssAgentSurface({ onCreditsExhausted }: OssAgentSurfaceProps) {
         agentName="OpenUI OSS"
         starterVariant="short"
         starters={OSS_STARTERS}
+        onUserMessageAccepted={({ source }) => {
+          if (source === "programmatic") return;
+          captureDemoAgentInteraction({
+            demo: "openui_chat",
+            variant: "oss",
+            model: DEFAULT_MODEL,
+            interaction_source: source,
+          });
+        }}
       >
         <AgentInterface.Welcome
           title="Build with OpenUI OSS"
diff --git a/docs/app/compare/_components/agent-surfaces/cloud-agent-surface.tsx b/docs/app/compare/_components/agent-surfaces/cloud-agent-surface.tsx
index fd65d8217..fc8732eaf 100644
--- a/docs/app/compare/_components/agent-surfaces/cloud-agent-surface.tsx
+++ b/docs/app/compare/_components/agent-surfaces/cloud-agent-surface.tsx
@@ -5,6 +5,7 @@ import { CLOUD_USER_ID_HEADER, getOrCreateCloudUserId } from "@/lib/openui-cloud
 import { AgentInterface } from "@openuidev/react-ui";
 import { artifactRenderers, chatLibrary, useOpenuiCloudStorage } from "@openuidev/thesys";
 import { useMemo, useState } from "react";
+import { captureComparisonRenderedAction } from "../comparison-analytics";
 import type { ComparisonControllerRegistry } from "../comparison-mode-controller";
 import { ComparisonModeControllerBridge } from "../comparison-mode-controller";
 import { ComparisonSurfaceWelcome } from "./comparison-surface-welcome";
@@ -40,6 +41,10 @@ export function CloudAgentSurface({ registry }: CloudAgentSurfaceProps) {
         componentLibrary={chatLibrary}
         artifactRenderers={artifactRenderers}
         scrollVariant="always"
+        onUserMessageAccepted={({ source }) => {
+          if (source !== "rendered_action") return;
+          captureComparisonRenderedAction("cloud");
+        }}
       >
         <AgentInterface.Sidebar />
         <AgentInterface.Welcome>
diff --git a/docs/app/compare/_components/agent-surfaces/oss-agent-surface.tsx b/docs/app/compare/_components/agent-surfaces/oss-agent-surface.tsx
index 20ef99a7b..7498ab67d 100644
--- a/docs/app/compare/_components/agent-surfaces/oss-agent-surface.tsx
+++ b/docs/app/compare/_components/agent-surfaces/oss-agent-surface.tsx
@@ -2,6 +2,7 @@
 
 import { AgentInterface } from "@openuidev/react-ui";
 import { openuiChatLibrary } from "@openuidev/react-ui/genui-lib";
+import { captureComparisonRenderedAction } from "../comparison-analytics";
 import type { ComparisonControllerRegistry } from "../comparison-mode-controller";
 import { ComparisonModeControllerBridge } from "../comparison-mode-controller";
 import { ComparisonSurfaceWelcome } from "./comparison-surface-welcome";
@@ -22,6 +23,10 @@ export function OssAgentSurface({ onCreditsExhausted, registry }: OssAgentSurfac
         componentLibrary={openuiChatLibrary}
         agentName="OpenUI OSS"
         scrollVariant="always"
+        onUserMessageAccepted={({ source }) => {
+          if (source !== "rendered_action") return;
+          captureComparisonRenderedAction("oss");
+        }}
       >
         <AgentInterface.Sidebar />
         <AgentInterface.Welcome>
diff --git a/docs/app/compare/_components/compare-page-client.tsx b/docs/app/compare/_components/compare-page-client.tsx
index 5d6059246..225f549f6 100644
--- a/docs/app/compare/_components/compare-page-client.tsx
+++ b/docs/app/compare/_components/compare-page-client.tsx
@@ -23,7 +23,8 @@ import {
   getComparisonPair,
   type ComparisonPair,
 } from "./chat-types";
-import { ComparisonControls } from "./comparison-controls";
+import { captureComparisonPromptInteractions } from "./comparison-analytics";
+import { ComparisonControls, type ComparisonSubmissionSource } from "./comparison-controls";
 import type {
   ComparisonMode,
   ComparisonModeController,
@@ -148,15 +149,18 @@ export function ComparePageClient({
   }, [registry, unavailableModes]);
 
   const submitToAll = useCallback(
-    (content: string) => {
+    (content: string, source: ComparisonSubmissionSource) => {
       const controllers = getReadyControllers();
       if (!controllers) return;
       const states = controllers.map((controller) => controller.getSnapshot());
       if (states.some((state) => !state.isReady || state.isRunning)) return;
 
+      const availableModes = new Set(controllers.map(({ mode }) => mode));
+      const visibleModes = getComparisonPair(pair).modes.filter((mode) => availableModes.has(mode));
+      captureComparisonPromptInteractions(visibleModes, source);
       void Promise.allSettled(controllers.map((controller) => controller.send(content)));
     },
-    [getReadyControllers],
+    [getReadyControllers, pair],
   );
 
   const stopAll = useCallback(() => {
diff --git a/docs/app/compare/_components/comparison-analytics.test.ts b/docs/app/compare/_components/comparison-analytics.test.ts
new file mode 100644
index 000000000..5a1f688a3
--- /dev/null
+++ b/docs/app/compare/_components/comparison-analytics.test.ts
@@ -0,0 +1,63 @@
+import { beforeEach, describe, expect, it, vi } from "vitest";
+import { DEFAULT_MODEL } from "../../../lib/openui-cloud/models";
+
+const { captureDemoAgentInteraction } = vi.hoisted(() => ({
+  captureDemoAgentInteraction: vi.fn(),
+}));
+
+vi.mock("../../../lib/demo-analytics", () => ({
+  captureDemoAgentInteraction,
+}));
+
+import {
+  captureComparisonPromptInteractions,
+  captureComparisonRenderedAction,
+} from "./comparison-analytics";
+
+beforeEach(() => {
+  captureDemoAgentInteraction.mockReset();
+});
+
+describe("comparison analytics", () => {
+  it("captures one model-attributed event for each visible comparison mode", () => {
+    captureComparisonPromptInteractions(["markdown", "cloud"], "composer");
+
+    expect(captureDemoAgentInteraction).toHaveBeenCalledTimes(2);
+    expect(captureDemoAgentInteraction).toHaveBeenNthCalledWith(1, {
+      demo: "compare",
+      variant: "markdown",
+      model: DEFAULT_MODEL,
+      interaction_source: "composer",
+    });
+    expect(captureDemoAgentInteraction).toHaveBeenNthCalledWith(2, {
+      demo: "compare",
+      variant: "cloud",
+      model: DEFAULT_MODEL,
+      interaction_source: "composer",
+    });
+  });
+
+  it("captures only modes that actually remain available", () => {
+    captureComparisonPromptInteractions(["oss"], "starter");
+
+    expect(captureDemoAgentInteraction).toHaveBeenCalledOnce();
+    expect(captureDemoAgentInteraction).toHaveBeenCalledWith({
+      demo: "compare",
+      variant: "oss",
+      model: DEFAULT_MODEL,
+      interaction_source: "starter",
+    });
+  });
+
+  it("captures a rendered action only for its target panel", () => {
+    captureComparisonRenderedAction("cloud");
+
+    expect(captureDemoAgentInteraction).toHaveBeenCalledOnce();
+    expect(captureDemoAgentInteraction).toHaveBeenCalledWith({
+      demo: "compare",
+      variant: "cloud",
+      model: DEFAULT_MODEL,
+      interaction_source: "rendered_action",
+    });
+  });
+});
diff --git a/docs/app/compare/_components/comparison-analytics.ts b/docs/app/compare/_components/comparison-analytics.ts
new file mode 100644
index 000000000..9357a5aa6
--- /dev/null
+++ b/docs/app/compare/_components/comparison-analytics.ts
@@ -0,0 +1,31 @@
+import {
+  captureDemoAgentInteraction,
+  type DemoInteractionSource,
+} from "../../../lib/demo-analytics";
+import { DEFAULT_MODEL } from "../../../lib/openui-cloud/models";
+import type { ComparisonMode } from "./comparison-mode-controller";
+
+export type ComparisonPromptSource = Extract<DemoInteractionSource, "composer" | "starter">;
+
+export function captureComparisonPromptInteractions(
+  modes: readonly ComparisonMode[],
+  interactionSource: ComparisonPromptSource,
+): void {
+  modes.forEach((mode) => {
+    captureDemoAgentInteraction({
+      demo: "compare",
+      variant: mode,
+      model: DEFAULT_MODEL,
+      interaction_source: interactionSource,
+    });
+  });
+}
+
+export function captureComparisonRenderedAction(mode: ComparisonMode): void {
+  captureDemoAgentInteraction({
+    demo: "compare",
+    variant: mode,
+    model: DEFAULT_MODEL,
+    interaction_source: "rendered_action",
+  });
+}
diff --git a/docs/app/compare/_components/comparison-controls.tsx b/docs/app/compare/_components/comparison-controls.tsx
index 6edd68063..6bd9b00cf 100644
--- a/docs/app/compare/_components/comparison-controls.tsx
+++ b/docs/app/compare/_components/comparison-controls.tsx
@@ -65,12 +65,14 @@ const COMPARISON_SUGGESTIONS = [
   },
 ] as const;
 
+export type ComparisonSubmissionSource = "composer" | "starter";
+
 interface ComparisonControlsProps {
   comparisonPair: ComparisonPair;
   isReady: boolean;
   isRunning: boolean;
   hasStarted: boolean;
-  onSubmit: (content: string) => void;
+  onSubmit: (content: string, source: ComparisonSubmissionSource) => void;
   onStop: () => void;
   onReset: () => void;
   isDegraded: boolean;
@@ -121,11 +123,11 @@ export function ComparisonControls({
     return () => observer.disconnect();
   }, [text]);
 
-  const submit = (content: string) => {
+  const submit = (content: string, source: ComparisonSubmissionSource) => {
     const next = content.trim();
     if (!next || !isReady || isRunning) return;
 
-    onSubmit(next);
+    onSubmit(next, source);
     setText("");
   };
 
@@ -152,7 +154,7 @@ export function ComparisonControls({
                   key={suggestion.label}
                   type="button"
                   className={styles.suggestionButton}
-                  onClick={() => submit(suggestion.prompt)}
+                  onClick={() => submit(suggestion.prompt, "starter")}
                   disabled={!isReady || isRunning || (needsCloud && !cloudEnabled)}
                   title={
                     needsCloud && !cloudEnabled
@@ -217,14 +219,14 @@ export function ComparisonControls({
             onKeyDown={(event) => {
               if (event.key === "Enter" && !event.shiftKey) {
                 event.preventDefault();
-                submit(text);
+                submit(text, "composer");
               }
             }}
           />
           <button
             type="button"
             className={styles.composerSubmit}
-            onClick={isRunning ? onStop : () => submit(text)}
+            onClick={isRunning ? onStop : () => submit(text, "composer")}
             disabled={!isRunning && (!isReady || text.trim().length === 0)}
             aria-label={
               isRunning
diff --git a/docs/app/demo/github/constants.ts b/docs/app/demo/github/constants.ts
index da0823b2b..d375ebaac 100644
--- a/docs/app/demo/github/constants.ts
+++ b/docs/app/demo/github/constants.ts
@@ -7,7 +7,7 @@ export const STREAM_RESULT = {
 } as const;
 export type StreamResult = (typeof STREAM_RESULT)[keyof typeof STREAM_RESULT];
 
-export const GITHUB_DEMO_MODEL = "anthropic/claude-sonnet-4-6";
+export { GITHUB_DEMO_MODEL } from "../../../lib/demo-models";
 export const GITHUB_DEMO_MODEL_LABEL = "Claude Sonnet 4.6";
 
 export type GitHubStarterIconKey =
diff --git a/docs/app/demo/github/page.tsx b/docs/app/demo/github/page.tsx
index de85d4c22..3577b96bb 100644
--- a/docs/app/demo/github/page.tsx
+++ b/docs/app/demo/github/page.tsx
@@ -1,6 +1,7 @@
 "use client";
 
 import { DemoCreditsDialog } from "@/components/DemoCreditsDialog";
+import { captureDemoAgentInteraction, type DemoInteractionSource } from "@/lib/demo-analytics";
 import { isDemoCreditsErrorPayload } from "@/lib/demo-credits";
 import { mergeStatements } from "@openuidev/react-lang";
 import { Button } from "@openuidev/react-ui";
@@ -26,6 +27,7 @@ import { Header } from "./components/Header/Header";
 import { PreviewPanel } from "./components/PreviewPanel/PreviewPanel";
 import { SavedSidebar } from "./components/SavedSidebar/SavedSidebar";
 import {
+  GITHUB_DEMO_MODEL,
   GITHUB_DEMO_MODEL_LABEL,
   GITHUB_STARTERS,
   STREAM_RESULT,
@@ -257,7 +259,10 @@ export default function GitHubDemoPage() {
 
   const abortRef = useRef<AbortController | null>(null);
   const responseRef = useRef("");
-  const pendingPromptRef = useRef<string | null>(null);
+  const pendingPromptRef = useRef<{
+    text: string;
+    interactionSource: DemoInteractionSource;
+  } | null>(null);
 
   const isStreaming = status === "streaming";
   const hasDashboard = dashboardCode !== null;
@@ -348,10 +353,16 @@ export default function GitHubDemoPage() {
   // ── Send message ─────────────────────────────────────────────────────
 
   const send = useCallback(
-    async (text: string) => {
+    async (text: string, interactionSource: DemoInteractionSource) => {
       if (!text.trim() || isStreaming) return;
       const trimmed = text.trim();
 
+      captureDemoAgentInteraction({
+        demo: "github_dashboard",
+        model: GITHUB_DEMO_MODEL,
+        interaction_source: interactionSource,
+      });
+
       setConvCollapsed(false);
       setStatus("streaming");
       setStartTime(null);
@@ -486,9 +497,9 @@ export default function GitHubDemoPage() {
   // Process pending prompt after GitHub connect
   useEffect(() => {
     if (githubUsername && toolProvider && pendingPromptRef.current) {
-      const p = pendingPromptRef.current;
+      const pendingPrompt = pendingPromptRef.current;
       pendingPromptRef.current = null;
-      send(p);
+      send(pendingPrompt.text, pendingPrompt.interactionSource);
     }
   }, [githubUsername, toolProvider, send]);
 
@@ -500,7 +511,10 @@ export default function GitHubDemoPage() {
 
   const handleConnectAndPrompt = useCallback(
     (username: string, promptText: string) => {
-      pendingPromptRef.current = promptText;
+      pendingPromptRef.current = {
+        text: promptText,
+        interactionSource: "starter",
+      };
       handleConnect(username);
     },
     [handleConnect],
@@ -596,7 +610,7 @@ export default function GitHubDemoPage() {
                         className="gh-starter-card"
                         variant="tertiary"
                         size="large"
-                        onClick={() => send(s.prompt)}
+                        onClick={() => send(s.prompt, "starter")}
                         disabled={isStreaming}
                       >
                         <span className={`gh-starter-icon gh-tone-${s.tone}`}>
@@ -770,7 +784,7 @@ export default function GitHubDemoPage() {
                           (typeof event.params?.context === "string" ? event.params.context : "") ||
                           event.humanFriendlyMessage ||
                           "";
-                        if (text) send(text);
+                        if (text) send(text, "rendered_action");
                       } else if (event.type === "open_url") {
                         const url = event.params?.["url"] as string | undefined;
                         if (url) window.open(url, "_blank");
@@ -798,7 +812,7 @@ export default function GitHubDemoPage() {
                 streamingText={streamingText}
                 isStreaming={isStreaming}
                 elapsed={elapsed}
-                onSend={send}
+                onSend={(text) => send(text, "composer")}
                 onStop={handleStop}
                 hasDashboard={hasDashboard}
                 responseHasCode={streamResponseHasCode}
diff --git a/docs/app/demos/constants.ts b/docs/app/demos/constants.ts
index 49abbf933..7d3919b49 100644
--- a/docs/app/demos/constants.ts
+++ b/docs/app/demos/constants.ts
@@ -1,11 +1,9 @@
+import { OPENUI_VS_JSON_MODELS } from "../../lib/demo-models";
+
 export type Theme = "system" | "light" | "dark";
 export type Status = "idle" | "streaming" | "done" | "error";
 
-export const MODELS = [
-  "anthropic/claude-sonnet-4.6",
-  "anthropic/claude-haiku-4.5",
-  "openai/gpt-5.2",
-] as const;
+export const MODELS = OPENUI_VS_JSON_MODELS;
 export type Model = (typeof MODELS)[number];
 
 export const STARTER_PROMPTS = [
diff --git a/docs/app/demos/page.tsx b/docs/app/demos/page.tsx
index da43d4605..52f40d753 100644
--- a/docs/app/demos/page.tsx
+++ b/docs/app/demos/page.tsx
@@ -1,6 +1,7 @@
 "use client";
 
 import { DemoCreditsDialog } from "@/components/DemoCreditsDialog";
+import { captureDemoAgentInteraction } from "@/lib/demo-analytics";
 import { isDemoCreditsErrorPayload } from "@/lib/demo-credits";
 import { Send, Square } from "lucide-react";
 import { useTheme } from "next-themes";
@@ -44,6 +45,12 @@ export default function DemosPage() {
   const handleSubmit = useCallback(async () => {
     if (!prompt.trim() || status === "streaming") return;
 
+    captureDemoAgentInteraction({
+      demo: "openui_vs_json",
+      model,
+      interaction_source: "composer",
+    });
+
     abortRef.current?.abort();
     const controller = new AbortController();
     abortRef.current = controller;
diff --git a/docs/lib/demo-analytics.test.ts b/docs/lib/demo-analytics.test.ts
new file mode 100644
index 000000000..6445f7a38
--- /dev/null
+++ b/docs/lib/demo-analytics.test.ts
@@ -0,0 +1,216 @@
+import { afterEach, describe, expect, it, vi } from "vitest";
+import { GITHUB_DEMO_MODEL } from "./demo-models";
+import { DEFAULT_MODEL } from "./openui-cloud/models";
+
+const { capture } = vi.hoisted(() => ({
+  capture: vi.fn(),
+}));
+
+vi.mock("./analytics", () => ({
+  analytics: { capture },
+}));
+
+import {
+  captureDemoAgentInteraction,
+  DEMO_AGENT_INTERACTION_EVENT,
+  getDemoAgentInteractionProperties,
+  type DemoAgentInteraction,
+} from "./demo-analytics";
+
+afterEach(() => {
+  capture.mockReset();
+  vi.unstubAllGlobals();
+});
+
+describe("getDemoAgentInteractionProperties", () => {
+  it("builds the complete bounded event payload", () => {
+    expect(
+      getDemoAgentInteractionProperties({
+        demo: "compare",
+        variant: "markdown",
+        model: DEFAULT_MODEL,
+        interaction_source: "starter",
+      }),
+    ).toEqual({
+      demo: "compare",
+      variant: "markdown",
+      model: DEFAULT_MODEL,
+      interaction_source: "starter",
+    });
+  });
+
+  it("omits absent and unrecognized variants", () => {
+    expect(
+      getDemoAgentInteractionProperties({
+        demo: "github_dashboard",
+        model: GITHUB_DEMO_MODEL,
+        interaction_source: "starter",
+      }),
+    ).toEqual({
+      demo: "github_dashboard",
+      model: GITHUB_DEMO_MODEL,
+      interaction_source: "starter",
+    });
+
+    expect(
+      getDemoAgentInteractionProperties({
+        demo: "openui_vs_json",
+        variant: "a prompt must never become a dimension",
+        model: "openai/gpt-5.2",
+        interaction_source: "composer",
+      }),
+    ).toEqual({
+      demo: "openui_vs_json",
+      model: "openai/gpt-5.2",
+      interaction_source: "composer",
+    });
+  });
+
+  it("allows canonical model identifiers", () => {
+    expect(
+      getDemoAgentInteractionProperties({
+        demo: "openui_chat",
+        variant: "cloud",
+        model: "anthropic/claude-sonnet-5",
+        interaction_source: "composer",
+      }),
+    ).toEqual({
+      demo: "openui_chat",
+      variant: "cloud",
+      model: "anthropic/claude-sonnet-5",
+      interaction_source: "composer",
+    });
+  });
+
+  it("drops variants that belong to a different demo", () => {
+    expect(
+      getDemoAgentInteractionProperties({
+        demo: "compare",
+        variant: "markdown_vs_cloud",
+        model: DEFAULT_MODEL,
+        interaction_source: "composer",
+      }),
+    ).toEqual({
+      demo: "compare",
+      model: DEFAULT_MODEL,
+      interaction_source: "composer",
+    });
+
+    expect(
+      getDemoAgentInteractionProperties({
+        demo: "github_dashboard",
+        variant: "oss",
+        model: GITHUB_DEMO_MODEL,
+        interaction_source: "composer",
+      }),
+    ).toEqual({
+      demo: "github_dashboard",
+      model: GITHUB_DEMO_MODEL,
+      interaction_source: "composer",
+    });
+  });
+
+  it("does not forward extra or content-bearing fields", () => {
+    const interaction = {
+      demo: "openui_chat",
+      variant: "cloud",
+      model: DEFAULT_MODEL,
+      interaction_source: "rendered_action",
+      prompt: "private prompt",
+      messages: ["private response"],
+      thread_id: "private-thread",
+    } as DemoAgentInteraction & Record<string, unknown>;
+
+    expect(getDemoAgentInteractionProperties(interaction)).toEqual({
+      demo: "openui_chat",
+      variant: "cloud",
+      model: DEFAULT_MODEL,
+      interaction_source: "rendered_action",
+    });
+  });
+
+  it("rejects malformed core dimensions at runtime", () => {
+    expect(getDemoAgentInteractionProperties(null as unknown as DemoAgentInteraction)).toBeNull();
+
+    expect(
+      getDemoAgentInteractionProperties({
+        demo: "unknown",
+        interaction_source: "composer",
+      } as unknown as DemoAgentInteraction),
+    ).toBeNull();
+
+    expect(
+      getDemoAgentInteractionProperties({
+        demo: "compare",
+        model: DEFAULT_MODEL,
+        interaction_source: "click",
+      } as unknown as DemoAgentInteraction),
+    ).toBeNull();
+
+    expect(
+      getDemoAgentInteractionProperties({
+        demo: "github_dashboard",
+        model: DEFAULT_MODEL,
+        interaction_source: "composer",
+      }),
+    ).toBeNull();
+  });
+});
+
+describe("captureDemoAgentInteraction", () => {
+  it("does not capture during server rendering", () => {
+    captureDemoAgentInteraction({
+      demo: "github_dashboard",
+      model: GITHUB_DEMO_MODEL,
+      interaction_source: "composer",
+    });
+
+    expect(capture).not.toHaveBeenCalled();
+  });
+
+  it("captures exactly one allowlisted event in the browser", () => {
+    vi.stubGlobal("window", {});
+
+    captureDemoAgentInteraction({
+      demo: "openui_chat",
+      variant: "oss",
+      model: DEFAULT_MODEL,
+      interaction_source: "starter",
+    });
+
+    expect(capture).toHaveBeenCalledOnce();
+    expect(capture).toHaveBeenCalledWith(DEMO_AGENT_INTERACTION_EVENT, {
+      demo: "openui_chat",
+      variant: "oss",
+      model: DEFAULT_MODEL,
+      interaction_source: "starter",
+    });
+  });
+
+  it("does not capture malformed core dimensions", () => {
+    vi.stubGlobal("window", {});
+
+    captureDemoAgentInteraction({
+      demo: "other",
+      interaction_source: "composer",
+    } as unknown as DemoAgentInteraction);
+
+    expect(capture).not.toHaveBeenCalled();
+  });
+
+  it("does not throw when the analytics client fails synchronously", () => {
+    vi.stubGlobal("window", {});
+    capture.mockImplementationOnce(() => {
+      throw new Error("capture failed");
+    });
+
+    expect(() =>
+      captureDemoAgentInteraction({
+        demo: "compare",
+        variant: "oss",
+        model: DEFAULT_MODEL,
+        interaction_source: "rendered_action",
+      }),
+    ).not.toThrow();
+  });
+});
diff --git a/docs/lib/demo-analytics.ts b/docs/lib/demo-analytics.ts
new file mode 100644
index 000000000..67c94fb97
--- /dev/null
+++ b/docs/lib/demo-analytics.ts
@@ -0,0 +1,87 @@
+import { analytics } from "./analytics";
+import { DEMO_MODEL_IDS } from "./demo-models";
+
+export const DEMO_AGENT_INTERACTION_EVENT = "demo_agent_interaction";
+
+export const DEMO_AGENT_INTERACTION_DEMOS = [
+  "compare",
+  "github_dashboard",
+  "openui_chat",
+  "openui_vs_json",
+] as const;
+
+export const DEMO_INTERACTION_SOURCES = ["composer", "starter", "rendered_action"] as const;
+
+export type DemoAgentInteractionDemo = (typeof DEMO_AGENT_INTERACTION_DEMOS)[number];
+export type DemoInteractionSource = (typeof DEMO_INTERACTION_SOURCES)[number];
+
+export interface DemoAgentInteraction {
+  demo: DemoAgentInteractionDemo;
+  variant?: string;
+  model: string;
+  interaction_source: DemoInteractionSource;
+}
+
+export type DemoAgentInteractionProperties = DemoAgentInteraction;
+
+const DEMO_AGENT_INTERACTION_DEMO_SET = new Set<string>(DEMO_AGENT_INTERACTION_DEMOS);
+const DEMO_INTERACTION_SOURCE_SET = new Set<string>(DEMO_INTERACTION_SOURCES);
+const DEMO_VARIANTS: Record<DemoAgentInteractionDemo, ReadonlySet<string>> = {
+  compare: new Set(["markdown", "oss", "cloud"]),
+  github_dashboard: new Set(),
+  openui_chat: new Set(["oss", "cloud"]),
+  openui_vs_json: new Set(),
+};
+const DEMO_MODELS: Record<DemoAgentInteractionDemo, ReadonlySet<string>> = {
+  compare: new Set(DEMO_MODEL_IDS.compare),
+  github_dashboard: new Set(DEMO_MODEL_IDS.github_dashboard),
+  openui_chat: new Set(DEMO_MODEL_IDS.openui_chat),
+  openui_vs_json: new Set(DEMO_MODEL_IDS.openui_vs_json),
+};
+
+/**
+ * Builds the complete PostHog payload from an allowlist of low-cardinality
+ * fields. Unknown fields on a structurally compatible input are not forwarded.
+ */
+export function getDemoAgentInteractionProperties(
+  interaction: DemoAgentInteraction,
+): DemoAgentInteractionProperties | null {
+  if (
+    !interaction ||
+    typeof interaction !== "object" ||
+    !DEMO_AGENT_INTERACTION_DEMO_SET.has(interaction.demo) ||
+    !DEMO_INTERACTION_SOURCE_SET.has(interaction.interaction_source) ||
+    typeof interaction.model !== "string" ||
+    !DEMO_MODELS[interaction.demo].has(interaction.model)
+  ) {
+    return null;
+  }
+
+  const variant =
+    typeof interaction.variant === "string" &&
+    DEMO_VARIANTS[interaction.demo].has(interaction.variant)
+      ? interaction.variant
+      : undefined;
+
+  return {
+    demo: interaction.demo,
+    ...(variant ? { variant } : {}),
+    model: interaction.model,
+    interaction_source: interaction.interaction_source,
+  };
+}
+
+/**
+ * Records a user interaction without delaying or affecting the interaction.
+ * Server rendering and malformed inputs intentionally become no-ops.
+ */
+export function captureDemoAgentInteraction(interaction: DemoAgentInteraction): void {
+  const properties = getDemoAgentInteractionProperties(interaction);
+  if (!properties || typeof window === "undefined") return;
+
+  try {
+    analytics.capture(DEMO_AGENT_INTERACTION_EVENT, properties);
+  } catch {
+    // Analytics must never interfere with the user action being measured.
+  }
+}
diff --git a/docs/lib/demo-models.ts b/docs/lib/demo-models.ts
new file mode 100644
index 000000000..27aa122ae
--- /dev/null
+++ b/docs/lib/demo-models.ts
@@ -0,0 +1,16 @@
+import { DEFAULT_MODEL, MODEL_OPTIONS } from "./openui-cloud/models";
+
+export const GITHUB_DEMO_MODEL = "anthropic/claude-sonnet-4-6";
+
+export const OPENUI_VS_JSON_MODELS = [
+  "anthropic/claude-sonnet-4.6",
+  "anthropic/claude-haiku-4.5",
+  "openai/gpt-5.2",
+] as const;
+
+export const DEMO_MODEL_IDS = {
+  compare: [DEFAULT_MODEL],
+  github_dashboard: [GITHUB_DEMO_MODEL],
+  openui_chat: MODEL_OPTIONS.map(({ id }) => id),
+  openui_vs_json: OPENUI_VS_JSON_MODELS,
+} as const;
diff --git a/docs/lib/thesys-link-attribution.test.ts b/docs/lib/thesys-link-attribution.test.ts
new file mode 100644
index 000000000..c713f7b32
--- /dev/null
+++ b/docs/lib/thesys-link-attribution.test.ts
@@ -0,0 +1,53 @@
+import { describe, expect, it } from "vitest";
+import {
+  addThesysLinkAttribution,
+  POSTHOG_DISTINCT_ID_PARAM,
+  POSTHOG_SESSION_ID_PARAM,
+} from "./thesys-link-attribution";
+
+describe("addThesysLinkAttribution", () => {
+  it("forwards anonymous PostHog identity to a Thesys console link", () => {
+    const attributed = new URL(
+      addThesysLinkAttribution(
+        "https://console.thesys.dev/keys?ref=docs#api",
+        "https://openui.com/demo/github",
+        "019b0630-3100-7d69-8ee9-99b639e6474a",
+        "019b0631-3100-7d69-8ee9-99b639e6474b",
+      ),
+    );
+
+    expect(attributed.pathname).toBe("/keys");
+    expect(attributed.searchParams.get("ref")).toBe("docs");
+    expect(attributed.searchParams.get("utm_source")).toBe("openui");
+    expect(attributed.searchParams.get("utm_medium")).toBe("referral");
+    expect(attributed.searchParams.get("utm_campaign")).toBe("openui_to_thesys");
+    expect(attributed.searchParams.get(POSTHOG_DISTINCT_ID_PARAM)).toBe(
+      "019b0630-3100-7d69-8ee9-99b639e6474a",
+    );
+    expect(attributed.searchParams.get(POSTHOG_SESSION_ID_PARAM)).toBe(
+      "019b0631-3100-7d69-8ee9-99b639e6474b",
+    );
+    expect(attributed.hash).toBe("#api");
+  });
+
+  it("does not decorate links outside thesys.dev", () => {
+    expect(
+      addThesysLinkAttribution(
+        "https://example.com/?posthog_distinct_id=keep",
+        "https://openui.com",
+        "anonymous-id",
+        "session-id",
+      ),
+    ).toBe("https://example.com/?posthog_distinct_id=keep");
+  });
+
+  it("adds campaign attribution without inventing missing PostHog IDs", () => {
+    const attributed = new URL(
+      addThesysLinkAttribution("https://thesys.dev", "https://openui.com", undefined, undefined),
+    );
+
+    expect(attributed.searchParams.get("utm_source")).toBe("openui");
+    expect(attributed.searchParams.has(POSTHOG_DISTINCT_ID_PARAM)).toBe(false);
+    expect(attributed.searchParams.has(POSTHOG_SESSION_ID_PARAM)).toBe(false);
+  });
+});
diff --git a/docs/package.json b/docs/package.json
index 3f0445aa4..ce0a6726e 100644
--- a/docs/package.json
+++ b/docs/package.json
@@ -8,6 +8,7 @@
     "build": "next build --no-mangling",
     "dev": "pnpm generate:prompts && next dev",
     "start": "next start",
+    "test": "vitest run",
     "types:check": "fumadocs-mdx && next typegen && tsc --noEmit",
     "postinstall": "fumadocs-mdx",
     "lint": "eslint",
@@ -53,6 +54,7 @@
     "@types/react-dom": "^19.2.3",
     "eslint-config-next": "16.2.6",
     "postcss": "^8.5.6",
-    "tailwindcss": "^4.1.18"
+    "tailwindcss": "^4.1.18",
+    "vitest": "^4.1.0"
   }
 }
diff --git a/docs/plans/frontend-posthog-demo-analytics.md b/docs/plans/frontend-posthog-demo-analytics.md
new file mode 100644
index 000000000..dba1e555a
--- /dev/null
+++ b/docs/plans/frontend-posthog-demo-analytics.md
@@ -0,0 +1,185 @@
+# Frontend PostHog Analytics Plan
+
+## Goal
+
+Capture model-attributed PostHog events whenever a user sends an accepted
+prompt or triggers an agent-directed action in every hosted demo. Most turns
+emit one event; `/compare` emits one per visible panel.
+
+## Scope
+
+Instrument the four demos in the website navigation:
+
+- `/compare`
+- `/demo/github`
+- `/chat`
+- `/demos`
+
+Standalone `examples/*` apps remain out of scope because downstream developers
+can run them locally.
+
+## Event contract
+
+Event name:
+
+```text
+demo_agent_interaction
+```
+
+Properties:
+
+```ts
+type DemoAgentInteraction = {
+  demo: "compare" | "github_dashboard" | "openui_chat" | "openui_vs_json";
+  variant?: string;
+  model: string;
+  interaction_source: "composer" | "starter" | "rendered_action";
+};
+```
+
+Variant meanings:
+
+| Demo               | Variant                                   |
+| ------------------ | ----------------------------------------- |
+| `compare`          | Visible panel: `markdown`, `oss`, `cloud` |
+| `openui_chat`      | `oss` or `cloud`                          |
+| `github_dashboard` | Omit                                      |
+| `openui_vs_json`   | Omit                                      |
+
+`model` is the canonical provider/model ID requested for that interaction.
+
+## Counting rules
+
+Capture once when an interaction passes validation and is about to be
+dispatched.
+
+Count:
+
+- Typed prompt submission
+- Starter that submits immediately
+- GitHub connect-time starter prompt
+- Follow-up prompt
+- Generated `continue_conversation` action
+
+Do not count:
+
+- Empty or blocked submissions
+- Typing, focus, or scrolling
+- Starter chips that only prefill an input
+- Loaded conversation history
+- Local form, tab, or component-state changes
+
+A `/compare` submission emits two events, one for each available mode in the
+selected visible pair. The third hidden controller still receives the prompt in
+the background but is not counted as a visible user interaction. A rendered
+action emits one event for the panel where it was triggered.
+
+## Implementation
+
+### 1. Add a shared demo analytics helper
+
+Create `docs/lib/demo-analytics.ts`.
+
+It will:
+
+- Define the event and property types.
+- Validate the bounded `demo`, `variant`, `model`, and `interaction_source`
+  values.
+- Call the existing helper in `docs/lib/analytics.ts`.
+- Remain browser-only, fire-and-forget, and fail-open.
+- Never initialize a second PostHog client.
+
+### 2. Expose neutral AgentInterface interaction hooks
+
+Add an optional, analytics-neutral callback to `AgentInterface` for accepted
+user turns.
+
+Built-in paths should identify their source as:
+
+- Composer: `composer`
+- Immediate starter: `starter`
+- Generated `continue_conversation`: `rendered_action`
+
+No PostHog code belongs in `react-ui` or `react-headless`. Those packages only
+expose the callback; analytics is enabled exclusively by the owned docs site.
+
+### 3. Instrument each demo
+
+| Demo           | Capture point                                                                                                                                                                                                                |
+| -------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
+| `/demos`       | Capture in `docs/app/demos/page.tsx::handleSubmit`, after validation and before `fetch`. Starter chips remain prefill-only.                                                                                                  |
+| `/demo/github` | Extend the central `docs/app/demo/github/page.tsx::send` function to accept `interaction_source`. Propagate it through connect-time starters, regular starters, the composer, and rendered actions.                          |
+| `/chat`        | Pass the neutral callback to the OSS and Cloud `AgentInterface` instances in `docs/app/chat/_components/agent-surfaces/`. Set `variant` to `oss` or `cloud` and report the requested model.                                  |
+| `/compare`     | Capture shared prompts once per visible mode in `docs/app/compare/_components/compare-page-client.tsx::submitToAll`. Use the `AgentInterface` callback only for rendered actions that target an individual comparison panel. |
+
+### 4. Preserve privacy boundaries
+
+Never add these values as custom event properties:
+
+- Prompt or message content
+- Generated UI, code, or output
+- Action labels, context, or form state
+- GitHub usernames
+- URLs
+- Thread or Cloud user IDs
+- Tool arguments
+- Raw errors
+
+PostHog may still attach the SDK's standard page context to the event.
+
+### 5. Preserve anonymous-to-authenticated attribution
+
+Keep demo visitors anonymous in OpenUI. When they follow a `thesys.dev` link,
+forward PostHog's current anonymous distinct ID and session ID as dedicated
+query parameters; do not add either value to the custom event payload.
+
+Before initializing PostHog, the receiving console must validate and consume
+those parameters, bootstrap the forwarded distinct ID with
+`isIdentifiedID: false`, and remove both parameters from the address bar. The
+console's existing `posthog.identify(user.id)` call then merges the earlier
+anonymous demo events into the authenticated person. OpenUI and the console
+must use the same PostHog project, and logout must call `posthog.reset()`.
+
+## Validation
+
+Add tests covering:
+
+- One valid non-compare submission produces one event.
+- Empty and blocked submissions produce no event.
+- Composer, starter, and rendered-action sources are correct.
+- `/compare` emits exactly two events for a healthy selected pair.
+- Chat variants report `oss` and `cloud`.
+- Every event reports an allowlisted canonical model ID.
+- No prohibited content enters the event payload.
+- PostHog failures never interrupt the user interaction.
+- A valid forwarded anonymous ID is bootstrapped as anonymous and the handoff
+  parameters are scrubbed without removing unrelated query parameters.
+- Malformed, duplicate, stale, or future handoff values are rejected.
+
+Run:
+
+```bash
+pnpm --filter @openuidev/docs types:check
+pnpm --filter @openuidev/docs lint
+pnpm --filter @openuidev/docs format:check
+pnpm --filter @openuidev/docs build
+pnpm --filter @openuidev/react-headless test
+pnpm --filter @openuidev/react-ui test
+```
+
+Finally, smoke-test all four routes and verify their payloads in PostHog Live
+Events.
+
+## Acceptance criteria
+
+- Every accepted user turn outside `/compare` emits one
+  `demo_agent_interaction` event.
+- A healthy `/compare` prompt emits exactly two events, one per visible mode;
+  rendered actions emit one event for their target panel.
+- `demo`, `variant`, `model`, and `interaction_source` use only documented
+  bounded values.
+- Custom event properties contain no prompt, identity, generated-content, or
+  action payload data.
+- Anonymous demo history merges into the console's canonical user after
+  authentication without exposing identity IDs as event properties.
+- Analytics loading or capture failures cannot break a demo interaction.
diff --git a/packages/react-headless/src/index.ts b/packages/react-headless/src/index.ts
index 6866ab82c..e0ba07e8d 100644
--- a/packages/react-headless/src/index.ts
+++ b/packages/react-headless/src/index.ts
@@ -73,11 +73,14 @@ export type {
   ChatProviderProps,
   ChatStore,
   CreateMessage,
+  ProcessMessageOptions,
   Thread,
   ThreadActions,
   ThreadListActions,
   ThreadListState,
   ThreadState,
+  UserMessageAcceptedEvent,
+  UserMessageSource,
 } from "./store/types";
 
 export type {
diff --git a/packages/react-headless/src/store/ChatProvider.tsx b/packages/react-headless/src/store/ChatProvider.tsx
index b002e15a0..f12d88a13 100644
--- a/packages/react-headless/src/store/ChatProvider.tsx
+++ b/packages/react-headless/src/store/ChatProvider.tsx
@@ -22,10 +22,12 @@ export const ChatProvider: FC<ChatProviderProps> = ({
   llm,
   artifactRenderers,
   artifactCategories,
+  onUserMessageAccepted,
 }) => {
   const [resolvedStorage] = useState(() => storage ?? createDefaultInMemoryStorage());
-  const config = useRef({ storage: resolvedStorage, llm });
+  const config = useRef({ storage: resolvedStorage, llm, onUserMessageAccepted });
   config.current.llm = llm;
+  config.current.onUserMessageAccepted = onUserMessageAccepted;
   const [chatStore] = useState(() => createChatStore(config));
   const [detailedViewStore] = useState(() => createDetailedViewStore());
   const [threadContextStore] = useState(() => createThreadContextStore());
diff --git a/packages/react-headless/src/store/__tests__/__helpers/makeStore.ts b/packages/react-headless/src/store/__tests__/__helpers/makeStore.ts
index 01f8e6f77..f0d6eb6ee 100644
--- a/packages/react-headless/src/store/__tests__/__helpers/makeStore.ts
+++ b/packages/react-headless/src/store/__tests__/__helpers/makeStore.ts
@@ -1,10 +1,11 @@
 import { vi } from "vitest";
 import type { ChatLLM, ChatStorage, ThreadStorage } from "../../../adapters/types";
-import { createChatStore } from "../../createChatStore";
+import { createChatStore, type CreateChatStoreConfig } from "../../createChatStore";
 
 export interface MakeStoreOverrides extends Partial<ThreadStorage> {
   send?: ChatLLM["send"];
   streamProtocol?: ChatLLM["streamProtocol"];
+  onUserMessageAccepted?: CreateChatStoreConfig["onUserMessageAccepted"];
 }
 
 /**
@@ -13,7 +14,7 @@ export interface MakeStoreOverrides extends Partial<ThreadStorage> {
  * overridden gets a vi.fn() mock with a sensible default return.
  */
 export function makeStore(overrides: MakeStoreOverrides = {}) {
-  const { send, streamProtocol, ...threadOverrides } = overrides;
+  const { send, streamProtocol, onUserMessageAccepted, ...threadOverrides } = overrides;
 
   const storage: ChatStorage = {
     thread: {
@@ -35,5 +36,5 @@ export function makeStore(overrides: MakeStoreOverrides = {}) {
     streamProtocol: streamProtocol ?? { parse: async function* () {} },
   };
 
-  return createChatStore({ current: { storage, llm } });
+  return createChatStore({ current: { storage, llm, onUserMessageAccepted } });
 }
diff --git a/packages/react-headless/src/store/__tests__/createChatStore.test.ts b/packages/react-headless/src/store/__tests__/createChatStore.test.ts
index 1d28dfbab..a5afe4ad2 100644
--- a/packages/react-headless/src/store/__tests__/createChatStore.test.ts
+++ b/packages/react-headless/src/store/__tests__/createChatStore.test.ts
@@ -307,6 +307,29 @@ describe("createChatStore", () => {
       expect(send).toHaveBeenCalledOnce();
     });
 
+    it("reports the supplied source without exposing message content", async () => {
+      const onUserMessageAccepted = vi.fn();
+      const store = makeStore({ onUserMessageAccepted });
+      store.setState({ selectedThreadId: "t1" });
+
+      await store
+        .getState()
+        .processMessage({ role: "user", content: "private prompt" }, { source: "composer" });
+
+      expect(onUserMessageAccepted).toHaveBeenCalledOnce();
+      expect(onUserMessageAccepted).toHaveBeenCalledWith({ source: "composer" });
+    });
+
+    it("defaults direct calls to the programmatic source", async () => {
+      const onUserMessageAccepted = vi.fn();
+      const store = makeStore({ onUserMessageAccepted });
+      store.setState({ selectedThreadId: "t1" });
+
+      await store.getState().processMessage({ role: "user", content: "hello" });
+
+      expect(onUserMessageAccepted).toHaveBeenCalledWith({ source: "programmatic" });
+    });
+
     it("creates thread when none selected", async () => {
       const newThread = makeThread("t-auto");
       const createThread = vi.fn().mockResolvedValue(newThread);
@@ -326,9 +349,11 @@ describe("createChatStore", () => {
 
     it("no-ops when already running", async () => {
       const send = vi.fn().mockResolvedValue(new Response("", { status: 200 }));
+      const onUserMessageAccepted = vi.fn();
 
       const store = makeStore({
         send,
+        onUserMessageAccepted,
         streamProtocol: { parse: async function* () {} },
       });
       store.setState({ isRunning: true, selectedThreadId: "t1" });
@@ -336,6 +361,24 @@ describe("createChatStore", () => {
       await store.getState().processMessage({ role: "user", content: "hello" });
 
       expect(send).not.toHaveBeenCalled();
+      expect(onUserMessageAccepted).not.toHaveBeenCalled();
+    });
+
+    it("continues processing if the accepted-turn observer throws", async () => {
+      const send = vi.fn().mockResolvedValue(new Response("", { status: 200 }));
+      const store = makeStore({
+        send,
+        onUserMessageAccepted: () => {
+          throw new Error("observer failed");
+        },
+      });
+      store.setState({ selectedThreadId: "t1" });
+
+      await expect(
+        store.getState().processMessage({ role: "user", content: "hello" }),
+      ).resolves.toBeUndefined();
+
+      expect(send).toHaveBeenCalledOnce();
     });
 
     it("sets threadError on failure", async () => {
diff --git a/packages/react-headless/src/store/createChatStore.ts b/packages/react-headless/src/store/createChatStore.ts
index 582e05cc6..0b7df9f57 100644
--- a/packages/react-headless/src/store/createChatStore.ts
+++ b/packages/react-headless/src/store/createChatStore.ts
@@ -3,11 +3,12 @@ import { subscribeWithSelector } from "zustand/middleware";
 import { getResponseErrorMessage } from "../adapters/httpError";
 import type { ChatLLM, ChatStorage } from "../adapters/types";
 import { processStreamedMessage } from "../stream/processStreamedMessage";
-import type { ChatStore, Message, Thread, UserMessage } from "./types";
+import type { ChatStore, Message, Thread, UserMessage, UserMessageAcceptedEvent } from "./types";
 
 export interface CreateChatStoreConfig {
   storage: ChatStorage;
   llm: ChatLLM;
+  onUserMessageAccepted?: (event: UserMessageAcceptedEvent) => void;
 }
 
 const mergeThreadList = (existing: Thread[], incoming: Thread[]): Thread[] =>
@@ -140,7 +141,7 @@ export const createChatStore = (configRef: React.RefObject<CreateChatStoreConfig
 
       // ── Thread Actions ──
 
-      processMessage: async (message) => {
+      processMessage: async (message, options) => {
         const state = get();
         if (state.isRunning) return;
 
@@ -159,6 +160,14 @@ export const createChatStore = (configRef: React.RefObject<CreateChatStoreConfig
         });
         set((s) => ({ messages: [...s.messages, optimisticMessage] }));
 
+        try {
+          configRef.current.onUserMessageAccepted?.({
+            source: options?.source ?? "programmatic",
+          });
+        } catch {
+          // Observers must not prevent an accepted message from being sent.
+        }
+
         abortController.signal.addEventListener("abort", () => {
           set({ _abortController: null, isRunning: false });
         });
diff --git a/packages/react-headless/src/store/types.ts b/packages/react-headless/src/store/types.ts
index 4ddc3c870..65d6b4d00 100644
--- a/packages/react-headless/src/store/types.ts
+++ b/packages/react-headless/src/store/types.ts
@@ -5,6 +5,18 @@ import type { ArtifactRendererConfig } from "./artifactRendererTypes";
 export type { Message, UserMessage } from "../types/message";
 export type CreateMessage = Omit<UserMessage, "id">;
 
+export type UserMessageSource = "composer" | "starter" | "rendered_action" | "programmatic";
+
+export interface ProcessMessageOptions {
+  /** Identifies the UI path that initiated this accepted user turn. */
+  source?: UserMessageSource;
+}
+
+export interface UserMessageAcceptedEvent {
+  /** The initiating UI path. Message content is intentionally not exposed. */
+  source: UserMessageSource;
+}
+
 export type Thread = {
   id: string;
   title: string;
@@ -51,7 +63,7 @@ export type ThreadState = {
 };
 
 export type ThreadActions = {
-  processMessage: (message: CreateMessage) => Promise<void>;
+  processMessage: (message: CreateMessage, options?: ProcessMessageOptions) => Promise<void>;
   appendMessages: (...messages: Message[]) => void;
   updateMessage: (message: Message) => void;
   setMessages: (messages: Message[]) => void;
@@ -91,5 +103,11 @@ export interface ChatProviderProps {
    * artifact browser's pre-applied filters, and workspace section grouping.
    */
   artifactCategories?: ArtifactCategory[];
+  /**
+   * Called once after a user turn is accepted for processing. Rejected turns
+   * (for example, while another turn is running) do not trigger the callback.
+   * The event intentionally excludes message content.
+   */
+  onUserMessageAccepted?: (event: UserMessageAcceptedEvent) => void;
   children: React.ReactNode;
 }
diff --git a/packages/react-ui/src/components/AgentInterface/AgentInterface.tsx b/packages/react-ui/src/components/AgentInterface/AgentInterface.tsx
index cb90cd7b9..19e32e8b0 100644
--- a/packages/react-ui/src/components/AgentInterface/AgentInterface.tsx
+++ b/packages/react-ui/src/components/AgentInterface/AgentInterface.tsx
@@ -183,6 +183,7 @@ export const AgentInterface: AgentInterfaceComponent = ((props: AgentInterfacePr
     llm,
     artifactRenderers,
     artifactCategories,
+    onUserMessageAccepted,
     componentLibrary,
     components,
     theme,
@@ -240,6 +241,7 @@ export const AgentInterface: AgentInterfaceComponent = ((props: AgentInterfacePr
         llm={llm}
         artifactRenderers={artifactRenderers}
         artifactCategories={artifactCategories}
+        onUserMessageAccepted={onUserMessageAccepted}
       >
         <NavProvider path={path} defaultPath={defaultPath} onNavigate={onNavigate}>
           <StartersProvider starters={starters} starterVariant={starterVariant}>
diff --git a/packages/react-ui/src/components/AgentInterface/ConversationStarter.tsx b/packages/react-ui/src/components/AgentInterface/ConversationStarter.tsx
index 0c3782b5d..899ac2b62 100644
--- a/packages/react-ui/src/components/AgentInterface/ConversationStarter.tsx
+++ b/packages/react-ui/src/components/AgentInterface/ConversationStarter.tsx
@@ -111,10 +111,13 @@ export const ConversationStarter = ({
       onSelect(starter);
       return;
     }
-    processMessage({
-      role: "user",
-      content: starter.prompt,
-    });
+    processMessage(
+      {
+        role: "user",
+        content: starter.prompt,
+      },
+      { source: "starter" },
+    );
   };
 
   // Only show when there are no messages
diff --git a/packages/react-ui/src/components/AgentInterface/README.md b/packages/react-ui/src/components/AgentInterface/README.md
index 2bad376c9..be1c1fdc8 100644
--- a/packages/react-ui/src/components/AgentInterface/README.md
+++ b/packages/react-ui/src/components/AgentInterface/README.md
@@ -156,14 +156,15 @@ Defined as `AgentInterfaceProps` in `AgentInterface.tsx`. It `extends Omit<ChatP
 
 **Forwarded to `ChatProvider`** (from `@openuidev/react-headless`):
 
-| Prop                 | Type                                     | Notes                                                                                                |
-| -------------------- | ---------------------------------------- | ---------------------------------------------------------------------------------------------------- |
-| `storage`            | `ChatStorage`                            | Thread persistence (`listThreads`, `getMessages`, …) and optional `artifact` storage for the browser |
-| `llm`                | LLM transport                            | The streaming send adapter                                                                           |
-| `artifactRenderers`  | `AppRenderer[]`                          | Tool-name → renderer (`parser`/`preview`/`actual`); drives inline previews + detailed view           |
-| `artifactCategories` | `{ name; filter: { type: string[] } }[]` | Splits the artifact browser & workspace into sections                                                |
-
-> ⚠️ Only those four `ChatProviderProps` are actually forwarded (they're destructured explicitly in
+| Prop                    | Type                                             | Notes                                                                                                |
+| ----------------------- | ------------------------------------------------ | ---------------------------------------------------------------------------------------------------- |
+| `storage`               | `ChatStorage`                                    | Thread persistence (`listThreads`, `getMessages`, …) and optional `artifact` storage for the browser |
+| `llm`                   | LLM transport                                    | The streaming send adapter                                                                           |
+| `artifactRenderers`     | `AppRenderer[]`                                  | Tool-name → renderer (`parser`/`preview`/`actual`); drives inline previews + detailed view           |
+| `artifactCategories`    | `{ name; filter: { type: string[] } }[]`         | Splits the artifact browser & workspace into sections                                                |
+| `onUserMessageAccepted` | `(event: { source: UserMessageSource }) => void` | Observes accepted user turns without exposing message content                                        |
+
+> ⚠️ Only those five `ChatProviderProps` are actually forwarded (they're destructured explicitly in
 > `AgentInterface.tsx`). Other `ChatProviderProps` are accepted by the _type_ but not passed through.
 
 **AgentInterface-specific:**
diff --git a/packages/react-ui/src/components/AgentInterface/components/Composer.tsx b/packages/react-ui/src/components/AgentInterface/components/Composer.tsx
index 1aa51fdfd..dcc95926c 100644
--- a/packages/react-ui/src/components/AgentInterface/components/Composer.tsx
+++ b/packages/react-ui/src/components/AgentInterface/components/Composer.tsx
@@ -44,10 +44,13 @@ export const Composer = ({ className, placeholder = "Type your query here" }: Co
       return;
     }
 
-    processMessage({
-      role: "user",
-      content: textContent,
-    });
+    processMessage(
+      {
+        role: "user",
+        content: textContent,
+      },
+      { source: "composer" },
+    );
 
     setTextContent("");
   };
diff --git a/packages/react-ui/src/components/AgentInterface/components/DesktopWelcomeComposer.tsx b/packages/react-ui/src/components/AgentInterface/components/DesktopWelcomeComposer.tsx
index 683e4c621..5a20c4393 100644
--- a/packages/react-ui/src/components/AgentInterface/components/DesktopWelcomeComposer.tsx
+++ b/packages/react-ui/src/components/AgentInterface/components/DesktopWelcomeComposer.tsx
@@ -58,10 +58,13 @@ export const DesktopWelcomeComposer = ({
       return;
     }
 
-    processMessage({
-      role: "user",
-      content: textContent,
-    });
+    processMessage(
+      {
+        role: "user",
+        content: textContent,
+      },
+      { source: "composer" },
+    );
 
     setTextContent("");
   };
diff --git a/packages/react-ui/src/components/OpenUIChat/CustomComposerAdapter.tsx b/packages/react-ui/src/components/OpenUIChat/CustomComposerAdapter.tsx
index d89a3f48b..29e22880b 100644
--- a/packages/react-ui/src/components/OpenUIChat/CustomComposerAdapter.tsx
+++ b/packages/react-ui/src/components/OpenUIChat/CustomComposerAdapter.tsx
@@ -10,7 +10,7 @@ export const CustomComposerAdapter = ({ composer: Composer }: { composer: Compos
   return (
     <Composer
       onSend={(message: string) => {
-        processMessage({ role: "user", content: message });
+        processMessage({ role: "user", content: message }, { source: "composer" });
       }}
       onCancel={cancelMessage}
       isRunning={isRunning}
diff --git a/packages/react-ui/src/components/OpenUIChat/GenUIAssistantMessage.tsx b/packages/react-ui/src/components/OpenUIChat/GenUIAssistantMessage.tsx
index 1bd95c6c3..f6416a9c9 100644
--- a/packages/react-ui/src/components/OpenUIChat/GenUIAssistantMessage.tsx
+++ b/packages/react-ui/src/components/OpenUIChat/GenUIAssistantMessage.tsx
@@ -108,10 +108,13 @@ export const GenUIAssistantMessage = ({
         const contextPart = wrapContext(JSON.stringify(messageCtx));
         const llmMessage = `${contentPart}${contextPart}`;
 
-        processMessage({
-          role: "user",
-          content: llmMessage,
-        });
+        processMessage(
+          {
+            role: "user",
+            content: llmMessage,
+          },
+          { source: "rendered_action" },
+        );
       } else if (event.type === BuiltinActionType.OpenUrl) {
         const url = event.params?.["url"] as string | undefined;
         if (typeof window !== "undefined" && url) {
diff --git a/packages/react-ui/src/components/OpenUIChat/withChatProvider.tsx b/packages/react-ui/src/components/OpenUIChat/withChatProvider.tsx
index ab216af63..23afe00c9 100644
--- a/packages/react-ui/src/components/OpenUIChat/withChatProvider.tsx
+++ b/packages/react-ui/src/components/OpenUIChat/withChatProvider.tsx
@@ -26,6 +26,7 @@ export function withChatProvider<ExtraProps = {}>(WrappedComponent: React.Compon
       llm,
       artifactRenderers,
       artifactCategories,
+      onUserMessageAccepted,
       theme,
       disableThemeProvider,
       ...innerProps
@@ -65,6 +66,7 @@ export function withChatProvider<ExtraProps = {}>(WrappedComponent: React.Compon
           llm={llm}
           artifactRenderers={artifactRenderers}
           artifactCategories={artifactCategories}
+          onUserMessageAccepted={onUserMessageAccepted}
         >
           <WrappedComponent {...finalInnerProps} />
         </ChatProvider>
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index 2a9474cc1..f9809426c 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -179,6 +179,9 @@ importers:
       tailwindcss:
         specifier: ^4.1.18
         version: 4.3.3
+      vitest:
+        specifier: ^4.1.0
+        version: 4.1.10(@opentelemetry/api@1.9.1)(@types/node@22.20.1)(jsdom@26.1.0)(vite@7.3.6(@types/node@22.20.1)(jiti@2.7.0)(lightningcss@1.33.0)(sass@1.102.0)(terser@5.49.0)(tsx@4.23.1)(yaml@2.9.0))
 
   examples/fastapi-backend/frontend:
     dependencies:

From 15d998fc6f3408c7a468fd1de2b0171e0d0acaee Mon Sep 17 00:00:00 2001
From: zahlekhan <zahle@thesys.dev>
Date: Thu, 30 Jul 2026 19:14:22 +0530
Subject: [PATCH 2/5] test(docs): remove comparison analytics test

---
 .../_components/comparison-analytics.test.ts  | 63 -------------------
 1 file changed, 63 deletions(-)
 delete mode 100644 docs/app/compare/_components/comparison-analytics.test.ts

diff --git a/docs/app/compare/_components/comparison-analytics.test.ts b/docs/app/compare/_components/comparison-analytics.test.ts
deleted file mode 100644
index 5a1f688a3..000000000
--- a/docs/app/compare/_components/comparison-analytics.test.ts
+++ /dev/null
@@ -1,63 +0,0 @@
-import { beforeEach, describe, expect, it, vi } from "vitest";
-import { DEFAULT_MODEL } from "../../../lib/openui-cloud/models";
-
-const { captureDemoAgentInteraction } = vi.hoisted(() => ({
-  captureDemoAgentInteraction: vi.fn(),
-}));
-
-vi.mock("../../../lib/demo-analytics", () => ({
-  captureDemoAgentInteraction,
-}));
-
-import {
-  captureComparisonPromptInteractions,
-  captureComparisonRenderedAction,
-} from "./comparison-analytics";
-
-beforeEach(() => {
-  captureDemoAgentInteraction.mockReset();
-});
-
-describe("comparison analytics", () => {
-  it("captures one model-attributed event for each visible comparison mode", () => {
-    captureComparisonPromptInteractions(["markdown", "cloud"], "composer");
-
-    expect(captureDemoAgentInteraction).toHaveBeenCalledTimes(2);
-    expect(captureDemoAgentInteraction).toHaveBeenNthCalledWith(1, {
-      demo: "compare",
-      variant: "markdown",
-      model: DEFAULT_MODEL,
-      interaction_source: "composer",
-    });
-    expect(captureDemoAgentInteraction).toHaveBeenNthCalledWith(2, {
-      demo: "compare",
-      variant: "cloud",
-      model: DEFAULT_MODEL,
-      interaction_source: "composer",
-    });
-  });
-
-  it("captures only modes that actually remain available", () => {
-    captureComparisonPromptInteractions(["oss"], "starter");
-
-    expect(captureDemoAgentInteraction).toHaveBeenCalledOnce();
-    expect(captureDemoAgentInteraction).toHaveBeenCalledWith({
-      demo: "compare",
-      variant: "oss",
-      model: DEFAULT_MODEL,
-      interaction_source: "starter",
-    });
-  });
-
-  it("captures a rendered action only for its target panel", () => {
-    captureComparisonRenderedAction("cloud");
-
-    expect(captureDemoAgentInteraction).toHaveBeenCalledOnce();
-    expect(captureDemoAgentInteraction).toHaveBeenCalledWith({
-      demo: "compare",
-      variant: "cloud",
-      model: DEFAULT_MODEL,
-      interaction_source: "rendered_action",
-    });
-  });
-});

From dc3858c6e5813105ef68347d71befa10435989b2 Mon Sep 17 00:00:00 2001
From: zahlekhan <zahle@thesys.dev>
Date: Thu, 30 Jul 2026 19:24:19 +0530
Subject: [PATCH 3/5] refactor(docs): keep demo analytics docs-only

---
 .../agent-surfaces/cloud-agent-surface.tsx    |  32 +--
 .../agent-surfaces/oss-agent-surface.tsx      |  28 ++-
 .../agent-surfaces/cloud-agent-surface.tsx    |  22 ++-
 .../agent-surfaces/oss-agent-surface.tsx      |  25 ++-
 .../agent-surfaces/use-comparison-chat-llm.ts |  16 +-
 .../_components/comparison-analytics.ts       |   9 -
 docs/lib/demo-analytics.test.ts               |  48 +++++
 docs/lib/demo-analytics.ts                    |  54 +++++
 docs/lib/openui-cloud/chat-llm.ts             |  14 +-
 docs/plans/frontend-posthog-demo-analytics.md | 185 ------------------
 packages/react-headless/src/index.ts          |   3 -
 .../react-headless/src/store/ChatProvider.tsx |   4 +-
 .../store/__tests__/__helpers/makeStore.ts    |   7 +-
 .../store/__tests__/createChatStore.test.ts   |  43 ----
 .../src/store/createChatStore.ts              |  13 +-
 packages/react-headless/src/store/types.ts    |  20 +-
 .../AgentInterface/AgentInterface.tsx         |   2 -
 .../AgentInterface/ConversationStarter.tsx    |  11 +-
 .../src/components/AgentInterface/README.md   |  17 +-
 .../AgentInterface/components/Composer.tsx    |  11 +-
 .../components/DesktopWelcomeComposer.tsx     |  11 +-
 .../OpenUIChat/CustomComposerAdapter.tsx      |   2 +-
 .../OpenUIChat/GenUIAssistantMessage.tsx      |  11 +-
 .../OpenUIChat/withChatProvider.tsx           |   2 -
 24 files changed, 234 insertions(+), 356 deletions(-)
 delete mode 100644 docs/plans/frontend-posthog-demo-analytics.md

diff --git a/docs/app/chat/_components/agent-surfaces/cloud-agent-surface.tsx b/docs/app/chat/_components/agent-surfaces/cloud-agent-surface.tsx
index 9574c4e70..a6b341dc4 100644
--- a/docs/app/chat/_components/agent-surfaces/cloud-agent-surface.tsx
+++ b/docs/app/chat/_components/agent-surfaces/cloud-agent-surface.tsx
@@ -1,6 +1,9 @@
 "use client";
 
-import { captureDemoAgentInteraction } from "@/lib/demo-analytics";
+import {
+  captureDemoAgentInteraction,
+  getDemoInteractionSourceFromMessages,
+} from "@/lib/demo-analytics";
 import { createCloudChatLLM } from "@/lib/openui-cloud/chat-llm";
 import { DEFAULT_MODEL } from "@/lib/openui-cloud/models";
 import { CLOUD_USER_ID_HEADER, getOrCreateCloudUserId } from "@/lib/openui-cloud/user-id";
@@ -35,11 +38,27 @@ const CLOUD_STARTERS = [
     prompt: "Write a brief market-analysis report on the EV sector.",
   },
 ];
+const CLOUD_STARTER_PROMPTS = CLOUD_STARTERS.map((starter) => starter.prompt);
 
 export function CloudAgentSurface() {
   const [selectedModel, setSelectedModel] = useState(DEFAULT_MODEL);
   const [userId] = useState(getOrCreateCloudUserId);
-  const [llm] = useState(createCloudChatLLM);
+  const [llm] = useState(() =>
+    createCloudChatLLM(({ model, messages }) => {
+      const interactionSource = getDemoInteractionSourceFromMessages(
+        messages,
+        CLOUD_STARTER_PROMPTS,
+      );
+      if (!interactionSource) return;
+
+      captureDemoAgentInteraction({
+        demo: "openui_chat",
+        variant: "cloud",
+        model,
+        interaction_source: interactionSource,
+      });
+    }),
+  );
   const cloudFetch = useMemo<typeof fetch>(() => {
     return async (input, init) => {
       if (typeof input !== "string" || input !== "/api/openui-cloud/frontend-token") {
@@ -83,15 +102,6 @@ export function CloudAgentSurface() {
         scrollOnLoad={false}
         starterVariant="short"
         starters={CLOUD_STARTERS}
-        onUserMessageAccepted={({ source }) => {
-          if (source === "programmatic") return;
-          captureDemoAgentInteraction({
-            demo: "openui_chat",
-            variant: "cloud",
-            model: selectedModel,
-            interaction_source: source,
-          });
-        }}
       >
         <AgentInterface.MobileHeader
           className={styles.cloudMobileHeader}
diff --git a/docs/app/chat/_components/agent-surfaces/oss-agent-surface.tsx b/docs/app/chat/_components/agent-surfaces/oss-agent-surface.tsx
index f35b45b82..1b7163af3 100644
--- a/docs/app/chat/_components/agent-surfaces/oss-agent-surface.tsx
+++ b/docs/app/chat/_components/agent-surfaces/oss-agent-surface.tsx
@@ -1,6 +1,9 @@
 "use client";
 
-import { captureDemoAgentInteraction } from "@/lib/demo-analytics";
+import {
+  captureDemoAgentInteraction,
+  getDemoInteractionSourceFromMessages,
+} from "@/lib/demo-analytics";
 import { isDemoCreditsErrorPayload } from "@/lib/demo-credits";
 import { DEFAULT_MODEL } from "@/lib/openui-cloud/models";
 import {
@@ -38,11 +41,25 @@ const OSS_STARTERS = [
       "Show me a carousel of 3 popular travel destinations with images, descriptions, and best time to visit.",
   },
 ];
+const OSS_STARTER_PROMPTS = OSS_STARTERS.map((starter) => starter.prompt);
 
 export function OssAgentSurface({ onCreditsExhausted }: OssAgentSurfaceProps) {
   const llm = useMemo<ChatLLM>(
     () => ({
       send: async ({ messages, signal }) => {
+        const interactionSource = getDemoInteractionSourceFromMessages(
+          messages,
+          OSS_STARTER_PROMPTS,
+        );
+        if (interactionSource) {
+          captureDemoAgentInteraction({
+            demo: "openui_chat",
+            variant: "oss",
+            model: DEFAULT_MODEL,
+            interaction_source: interactionSource,
+          });
+        }
+
         const response = await fetch("/api/chat", {
           method: "POST",
           headers: { "Content-Type": "application/json" },
@@ -82,15 +99,6 @@ export function OssAgentSurface({ onCreditsExhausted }: OssAgentSurfaceProps) {
         agentName="OpenUI OSS"
         starterVariant="short"
         starters={OSS_STARTERS}
-        onUserMessageAccepted={({ source }) => {
-          if (source === "programmatic") return;
-          captureDemoAgentInteraction({
-            demo: "openui_chat",
-            variant: "oss",
-            model: DEFAULT_MODEL,
-            interaction_source: source,
-          });
-        }}
       >
         <AgentInterface.Welcome
           title="Build with OpenUI OSS"
diff --git a/docs/app/compare/_components/agent-surfaces/cloud-agent-surface.tsx b/docs/app/compare/_components/agent-surfaces/cloud-agent-surface.tsx
index fc8732eaf..be3c95456 100644
--- a/docs/app/compare/_components/agent-surfaces/cloud-agent-surface.tsx
+++ b/docs/app/compare/_components/agent-surfaces/cloud-agent-surface.tsx
@@ -1,11 +1,14 @@
 "use client";
 
+import {
+  captureDemoAgentInteraction,
+  getDemoInteractionSourceFromMessages,
+} from "@/lib/demo-analytics";
 import { createCloudChatLLM } from "@/lib/openui-cloud/chat-llm";
 import { CLOUD_USER_ID_HEADER, getOrCreateCloudUserId } from "@/lib/openui-cloud/user-id";
 import { AgentInterface } from "@openuidev/react-ui";
 import { artifactRenderers, chatLibrary, useOpenuiCloudStorage } from "@openuidev/thesys";
 import { useMemo, useState } from "react";
-import { captureComparisonRenderedAction } from "../comparison-analytics";
 import type { ComparisonControllerRegistry } from "../comparison-mode-controller";
 import { ComparisonModeControllerBridge } from "../comparison-mode-controller";
 import { ComparisonSurfaceWelcome } from "./comparison-surface-welcome";
@@ -16,7 +19,18 @@ interface CloudAgentSurfaceProps {
 
 export function CloudAgentSurface({ registry }: CloudAgentSurfaceProps) {
   const [userId] = useState(getOrCreateCloudUserId);
-  const [llm] = useState(createCloudChatLLM);
+  const [llm] = useState(() =>
+    createCloudChatLLM(({ model, messages }) => {
+      if (getDemoInteractionSourceFromMessages(messages) !== "rendered_action") return;
+
+      captureDemoAgentInteraction({
+        demo: "compare",
+        variant: "cloud",
+        model,
+        interaction_source: "rendered_action",
+      });
+    }),
+  );
   const cloudFetch = useMemo<typeof fetch>(() => {
     return async (input, init) => {
       if (typeof input !== "string" || input !== "/api/openui-cloud/frontend-token") {
@@ -41,10 +55,6 @@ export function CloudAgentSurface({ registry }: CloudAgentSurfaceProps) {
         componentLibrary={chatLibrary}
         artifactRenderers={artifactRenderers}
         scrollVariant="always"
-        onUserMessageAccepted={({ source }) => {
-          if (source !== "rendered_action") return;
-          captureComparisonRenderedAction("cloud");
-        }}
       >
         <AgentInterface.Sidebar />
         <AgentInterface.Welcome>
diff --git a/docs/app/compare/_components/agent-surfaces/oss-agent-surface.tsx b/docs/app/compare/_components/agent-surfaces/oss-agent-surface.tsx
index 7498ab67d..4b270f7b3 100644
--- a/docs/app/compare/_components/agent-surfaces/oss-agent-surface.tsx
+++ b/docs/app/compare/_components/agent-surfaces/oss-agent-surface.tsx
@@ -1,8 +1,13 @@
 "use client";
 
-import { AgentInterface } from "@openuidev/react-ui";
+import {
+  captureDemoAgentInteraction,
+  getDemoInteractionSourceFromMessages,
+} from "@/lib/demo-analytics";
+import { DEFAULT_MODEL } from "@/lib/openui-cloud/models";
+import { AgentInterface, type Message } from "@openuidev/react-ui";
 import { openuiChatLibrary } from "@openuidev/react-ui/genui-lib";
-import { captureComparisonRenderedAction } from "../comparison-analytics";
+import { useCallback } from "react";
 import type { ComparisonControllerRegistry } from "../comparison-mode-controller";
 import { ComparisonModeControllerBridge } from "../comparison-mode-controller";
 import { ComparisonSurfaceWelcome } from "./comparison-surface-welcome";
@@ -14,7 +19,17 @@ interface OssAgentSurfaceProps {
 }
 
 export function OssAgentSurface({ onCreditsExhausted, registry }: OssAgentSurfaceProps) {
-  const llm = useComparisonChatLLM("openui", onCreditsExhausted);
+  const observeSend = useCallback((messages: readonly Message[]) => {
+    if (getDemoInteractionSourceFromMessages(messages) !== "rendered_action") return;
+
+    captureDemoAgentInteraction({
+      demo: "compare",
+      variant: "oss",
+      model: DEFAULT_MODEL,
+      interaction_source: "rendered_action",
+    });
+  }, []);
+  const llm = useComparisonChatLLM("openui", onCreditsExhausted, observeSend);
 
   return (
     <div className="chat-agent-surface" data-chat-mode="oss">
@@ -23,10 +38,6 @@ export function OssAgentSurface({ onCreditsExhausted, registry }: OssAgentSurfac
         componentLibrary={openuiChatLibrary}
         agentName="OpenUI OSS"
         scrollVariant="always"
-        onUserMessageAccepted={({ source }) => {
-          if (source !== "rendered_action") return;
-          captureComparisonRenderedAction("oss");
-        }}
       >
         <AgentInterface.Sidebar />
         <AgentInterface.Welcome>
diff --git a/docs/app/compare/_components/agent-surfaces/use-comparison-chat-llm.ts b/docs/app/compare/_components/agent-surfaces/use-comparison-chat-llm.ts
index 0272e39bb..f2586c22e 100644
--- a/docs/app/compare/_components/agent-surfaces/use-comparison-chat-llm.ts
+++ b/docs/app/compare/_components/agent-surfaces/use-comparison-chat-llm.ts
@@ -1,7 +1,12 @@
 "use client";
 
 import { isDemoCreditsErrorPayload } from "@/lib/demo-credits";
-import { openAIAdapter, openAIMessageFormat, type ChatLLM } from "@openuidev/react-ui";
+import {
+  openAIAdapter,
+  openAIMessageFormat,
+  type ChatLLM,
+  type Message,
+} from "@openuidev/react-ui";
 import { useMemo } from "react";
 
 type ComparisonResponseMode = "markdown" | "openui";
@@ -13,10 +18,17 @@ type ComparisonResponseMode = "markdown" | "openui";
 export function useComparisonChatLLM(
   responseMode: ComparisonResponseMode,
   onCreditsExhausted: () => void,
+  onSend?: (messages: readonly Message[]) => void,
 ): ChatLLM {
   return useMemo<ChatLLM>(
     () => ({
       send: async ({ messages, signal }) => {
+        try {
+          onSend?.(messages);
+        } catch {
+          // Analytics observers must never interfere with the chat request.
+        }
+
         const response = await fetch("/api/chat", {
           method: "POST",
           headers: { "Content-Type": "application/json" },
@@ -36,7 +48,7 @@ export function useComparisonChatLLM(
       },
       streamProtocol: openAIAdapter(),
     }),
-    [onCreditsExhausted, responseMode],
+    [onCreditsExhausted, onSend, responseMode],
   );
 }
 
diff --git a/docs/app/compare/_components/comparison-analytics.ts b/docs/app/compare/_components/comparison-analytics.ts
index 9357a5aa6..958674654 100644
--- a/docs/app/compare/_components/comparison-analytics.ts
+++ b/docs/app/compare/_components/comparison-analytics.ts
@@ -20,12 +20,3 @@ export function captureComparisonPromptInteractions(
     });
   });
 }
-
-export function captureComparisonRenderedAction(mode: ComparisonMode): void {
-  captureDemoAgentInteraction({
-    demo: "compare",
-    variant: mode,
-    model: DEFAULT_MODEL,
-    interaction_source: "rendered_action",
-  });
-}
diff --git a/docs/lib/demo-analytics.test.ts b/docs/lib/demo-analytics.test.ts
index 6445f7a38..e0447774f 100644
--- a/docs/lib/demo-analytics.test.ts
+++ b/docs/lib/demo-analytics.test.ts
@@ -14,6 +14,7 @@ import {
   captureDemoAgentInteraction,
   DEMO_AGENT_INTERACTION_EVENT,
   getDemoAgentInteractionProperties,
+  getDemoInteractionSourceFromMessages,
   type DemoAgentInteraction,
 } from "./demo-analytics";
 
@@ -22,6 +23,53 @@ afterEach(() => {
   vi.unstubAllGlobals();
 });
 
+describe("getDemoInteractionSourceFromMessages", () => {
+  const starter = "Build a revenue dashboard";
+
+  it("classifies a matching first user turn as a starter", () => {
+    expect(
+      getDemoInteractionSourceFromMessages([{ role: "user", content: starter }], [starter]),
+    ).toBe("starter");
+  });
+
+  it("classifies the same text later in a thread as composer input", () => {
+    expect(
+      getDemoInteractionSourceFromMessages(
+        [
+          { role: "user", content: "First turn" },
+          { role: "assistant", content: "Response" },
+          { role: "user", content: starter },
+        ],
+        [starter],
+      ),
+    ).toBe("composer");
+  });
+
+  it("classifies the strict OpenUI action context as a rendered action", () => {
+    expect(
+      getDemoInteractionSourceFromMessages([
+        {
+          role: "user",
+          content:
+            ']]>openui:content\nContinue\n]]>openui:context\n["User clicked: Continue",{"choice":"a"}]',
+        },
+      ]),
+    ).toBe("rendered_action");
+  });
+
+  it("does not mistake arbitrary context or malformed content for an action", () => {
+    expect(
+      getDemoInteractionSourceFromMessages([
+        {
+          role: "user",
+          content: 'Prompt\n]]>openui:context\n["Not an action"]',
+        },
+      ]),
+    ).toBe("composer");
+    expect(getDemoInteractionSourceFromMessages([])).toBeNull();
+  });
+});
+
 describe("getDemoAgentInteractionProperties", () => {
   it("builds the complete bounded event payload", () => {
     expect(
diff --git a/docs/lib/demo-analytics.ts b/docs/lib/demo-analytics.ts
index 67c94fb97..9c0164e6e 100644
--- a/docs/lib/demo-analytics.ts
+++ b/docs/lib/demo-analytics.ts
@@ -24,6 +24,13 @@ export interface DemoAgentInteraction {
 
 export type DemoAgentInteractionProperties = DemoAgentInteraction;
 
+interface DemoInteractionMessage {
+  role?: unknown;
+  content?: unknown;
+}
+
+const OPENUI_CONTEXT_MARKER = "\n]]>openui:context\n";
+
 const DEMO_AGENT_INTERACTION_DEMO_SET = new Set<string>(DEMO_AGENT_INTERACTION_DEMOS);
 const DEMO_INTERACTION_SOURCE_SET = new Set<string>(DEMO_INTERACTION_SOURCES);
 const DEMO_VARIANTS: Record<DemoAgentInteractionDemo, ReadonlySet<string>> = {
@@ -39,6 +46,53 @@ const DEMO_MODELS: Record<DemoAgentInteractionDemo, ReadonlySet<string>> = {
   openui_vs_json: new Set(DEMO_MODEL_IDS.openui_vs_json),
 };
 
+/**
+ * Classifies the accepted user turn already present in a chat transport's
+ * message list. Message content is inspected only in memory and is never added
+ * to the analytics payload.
+ */
+export function getDemoInteractionSourceFromMessages(
+  messages: readonly DemoInteractionMessage[],
+  starterPrompts: readonly string[] = [],
+): DemoInteractionSource | null {
+  const userMessages = messages.filter((message) => message.role === "user");
+  const lastUserMessage = userMessages.at(-1);
+  if (!lastUserMessage) return null;
+
+  if (
+    typeof lastUserMessage.content === "string" &&
+    isRenderedActionMessage(lastUserMessage.content)
+  ) {
+    return "rendered_action";
+  }
+
+  if (
+    userMessages.length === 1 &&
+    typeof lastUserMessage.content === "string" &&
+    starterPrompts.includes(lastUserMessage.content)
+  ) {
+    return "starter";
+  }
+
+  return "composer";
+}
+
+function isRenderedActionMessage(content: string): boolean {
+  const markerIndex = content.lastIndexOf(OPENUI_CONTEXT_MARKER);
+  if (markerIndex === -1) return false;
+
+  try {
+    const context = JSON.parse(content.slice(markerIndex + OPENUI_CONTEXT_MARKER.length));
+    return (
+      Array.isArray(context) &&
+      typeof context[0] === "string" &&
+      context[0].startsWith("User clicked:")
+    );
+  } catch {
+    return false;
+  }
+}
+
 /**
  * Builds the complete PostHog payload from an allowlist of low-cardinality
  * fields. Unknown fields on a structurally compatible input are not forwarded.
diff --git a/docs/lib/openui-cloud/chat-llm.ts b/docs/lib/openui-cloud/chat-llm.ts
index 490b24f0c..32df3cbde 100644
--- a/docs/lib/openui-cloud/chat-llm.ts
+++ b/docs/lib/openui-cloud/chat-llm.ts
@@ -3,13 +3,19 @@ import {
   openAIConversationMessageFormat,
   openAIResponsesAdapter,
   type ChatLLM,
+  type Message,
 } from "@openuidev/react-headless";
 
 interface CloudChatLLM extends ChatLLM {
   setSelectedModel: (model: string) => void;
 }
 
-export function createCloudChatLLM(): CloudChatLLM {
+interface CloudChatSendEvent {
+  model: string;
+  messages: Message[];
+}
+
+export function createCloudChatLLM(onSend?: (event: CloudChatSendEvent) => void): CloudChatLLM {
   let selectedModel = DEFAULT_MODEL;
 
   return {
@@ -17,6 +23,12 @@ export function createCloudChatLLM(): CloudChatLLM {
       selectedModel = model;
     },
     async send({ threadId, messages, signal }) {
+      try {
+        onSend?.({ model: selectedModel, messages });
+      } catch {
+        // Analytics observers must never interfere with the chat request.
+      }
+
       return fetch("/api/openui-cloud/chat", {
         method: "POST",
         headers: { "Content-Type": "application/json" },
diff --git a/docs/plans/frontend-posthog-demo-analytics.md b/docs/plans/frontend-posthog-demo-analytics.md
deleted file mode 100644
index dba1e555a..000000000
--- a/docs/plans/frontend-posthog-demo-analytics.md
+++ /dev/null
@@ -1,185 +0,0 @@
-# Frontend PostHog Analytics Plan
-
-## Goal
-
-Capture model-attributed PostHog events whenever a user sends an accepted
-prompt or triggers an agent-directed action in every hosted demo. Most turns
-emit one event; `/compare` emits one per visible panel.
-
-## Scope
-
-Instrument the four demos in the website navigation:
-
-- `/compare`
-- `/demo/github`
-- `/chat`
-- `/demos`
-
-Standalone `examples/*` apps remain out of scope because downstream developers
-can run them locally.
-
-## Event contract
-
-Event name:
-
-```text
-demo_agent_interaction
-```
-
-Properties:
-
-```ts
-type DemoAgentInteraction = {
-  demo: "compare" | "github_dashboard" | "openui_chat" | "openui_vs_json";
-  variant?: string;
-  model: string;
-  interaction_source: "composer" | "starter" | "rendered_action";
-};
-```
-
-Variant meanings:
-
-| Demo               | Variant                                   |
-| ------------------ | ----------------------------------------- |
-| `compare`          | Visible panel: `markdown`, `oss`, `cloud` |
-| `openui_chat`      | `oss` or `cloud`                          |
-| `github_dashboard` | Omit                                      |
-| `openui_vs_json`   | Omit                                      |
-
-`model` is the canonical provider/model ID requested for that interaction.
-
-## Counting rules
-
-Capture once when an interaction passes validation and is about to be
-dispatched.
-
-Count:
-
-- Typed prompt submission
-- Starter that submits immediately
-- GitHub connect-time starter prompt
-- Follow-up prompt
-- Generated `continue_conversation` action
-
-Do not count:
-
-- Empty or blocked submissions
-- Typing, focus, or scrolling
-- Starter chips that only prefill an input
-- Loaded conversation history
-- Local form, tab, or component-state changes
-
-A `/compare` submission emits two events, one for each available mode in the
-selected visible pair. The third hidden controller still receives the prompt in
-the background but is not counted as a visible user interaction. A rendered
-action emits one event for the panel where it was triggered.
-
-## Implementation
-
-### 1. Add a shared demo analytics helper
-
-Create `docs/lib/demo-analytics.ts`.
-
-It will:
-
-- Define the event and property types.
-- Validate the bounded `demo`, `variant`, `model`, and `interaction_source`
-  values.
-- Call the existing helper in `docs/lib/analytics.ts`.
-- Remain browser-only, fire-and-forget, and fail-open.
-- Never initialize a second PostHog client.
-
-### 2. Expose neutral AgentInterface interaction hooks
-
-Add an optional, analytics-neutral callback to `AgentInterface` for accepted
-user turns.
-
-Built-in paths should identify their source as:
-
-- Composer: `composer`
-- Immediate starter: `starter`
-- Generated `continue_conversation`: `rendered_action`
-
-No PostHog code belongs in `react-ui` or `react-headless`. Those packages only
-expose the callback; analytics is enabled exclusively by the owned docs site.
-
-### 3. Instrument each demo
-
-| Demo           | Capture point                                                                                                                                                                                                                |
-| -------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
-| `/demos`       | Capture in `docs/app/demos/page.tsx::handleSubmit`, after validation and before `fetch`. Starter chips remain prefill-only.                                                                                                  |
-| `/demo/github` | Extend the central `docs/app/demo/github/page.tsx::send` function to accept `interaction_source`. Propagate it through connect-time starters, regular starters, the composer, and rendered actions.                          |
-| `/chat`        | Pass the neutral callback to the OSS and Cloud `AgentInterface` instances in `docs/app/chat/_components/agent-surfaces/`. Set `variant` to `oss` or `cloud` and report the requested model.                                  |
-| `/compare`     | Capture shared prompts once per visible mode in `docs/app/compare/_components/compare-page-client.tsx::submitToAll`. Use the `AgentInterface` callback only for rendered actions that target an individual comparison panel. |
-
-### 4. Preserve privacy boundaries
-
-Never add these values as custom event properties:
-
-- Prompt or message content
-- Generated UI, code, or output
-- Action labels, context, or form state
-- GitHub usernames
-- URLs
-- Thread or Cloud user IDs
-- Tool arguments
-- Raw errors
-
-PostHog may still attach the SDK's standard page context to the event.
-
-### 5. Preserve anonymous-to-authenticated attribution
-
-Keep demo visitors anonymous in OpenUI. When they follow a `thesys.dev` link,
-forward PostHog's current anonymous distinct ID and session ID as dedicated
-query parameters; do not add either value to the custom event payload.
-
-Before initializing PostHog, the receiving console must validate and consume
-those parameters, bootstrap the forwarded distinct ID with
-`isIdentifiedID: false`, and remove both parameters from the address bar. The
-console's existing `posthog.identify(user.id)` call then merges the earlier
-anonymous demo events into the authenticated person. OpenUI and the console
-must use the same PostHog project, and logout must call `posthog.reset()`.
-
-## Validation
-
-Add tests covering:
-
-- One valid non-compare submission produces one event.
-- Empty and blocked submissions produce no event.
-- Composer, starter, and rendered-action sources are correct.
-- `/compare` emits exactly two events for a healthy selected pair.
-- Chat variants report `oss` and `cloud`.
-- Every event reports an allowlisted canonical model ID.
-- No prohibited content enters the event payload.
-- PostHog failures never interrupt the user interaction.
-- A valid forwarded anonymous ID is bootstrapped as anonymous and the handoff
-  parameters are scrubbed without removing unrelated query parameters.
-- Malformed, duplicate, stale, or future handoff values are rejected.
-
-Run:
-
-```bash
-pnpm --filter @openuidev/docs types:check
-pnpm --filter @openuidev/docs lint
-pnpm --filter @openuidev/docs format:check
-pnpm --filter @openuidev/docs build
-pnpm --filter @openuidev/react-headless test
-pnpm --filter @openuidev/react-ui test
-```
-
-Finally, smoke-test all four routes and verify their payloads in PostHog Live
-Events.
-
-## Acceptance criteria
-
-- Every accepted user turn outside `/compare` emits one
-  `demo_agent_interaction` event.
-- A healthy `/compare` prompt emits exactly two events, one per visible mode;
-  rendered actions emit one event for their target panel.
-- `demo`, `variant`, `model`, and `interaction_source` use only documented
-  bounded values.
-- Custom event properties contain no prompt, identity, generated-content, or
-  action payload data.
-- Anonymous demo history merges into the console's canonical user after
-  authentication without exposing identity IDs as event properties.
-- Analytics loading or capture failures cannot break a demo interaction.
diff --git a/packages/react-headless/src/index.ts b/packages/react-headless/src/index.ts
index e0ba07e8d..6866ab82c 100644
--- a/packages/react-headless/src/index.ts
+++ b/packages/react-headless/src/index.ts
@@ -73,14 +73,11 @@ export type {
   ChatProviderProps,
   ChatStore,
   CreateMessage,
-  ProcessMessageOptions,
   Thread,
   ThreadActions,
   ThreadListActions,
   ThreadListState,
   ThreadState,
-  UserMessageAcceptedEvent,
-  UserMessageSource,
 } from "./store/types";
 
 export type {
diff --git a/packages/react-headless/src/store/ChatProvider.tsx b/packages/react-headless/src/store/ChatProvider.tsx
index f12d88a13..b002e15a0 100644
--- a/packages/react-headless/src/store/ChatProvider.tsx
+++ b/packages/react-headless/src/store/ChatProvider.tsx
@@ -22,12 +22,10 @@ export const ChatProvider: FC<ChatProviderProps> = ({
   llm,
   artifactRenderers,
   artifactCategories,
-  onUserMessageAccepted,
 }) => {
   const [resolvedStorage] = useState(() => storage ?? createDefaultInMemoryStorage());
-  const config = useRef({ storage: resolvedStorage, llm, onUserMessageAccepted });
+  const config = useRef({ storage: resolvedStorage, llm });
   config.current.llm = llm;
-  config.current.onUserMessageAccepted = onUserMessageAccepted;
   const [chatStore] = useState(() => createChatStore(config));
   const [detailedViewStore] = useState(() => createDetailedViewStore());
   const [threadContextStore] = useState(() => createThreadContextStore());
diff --git a/packages/react-headless/src/store/__tests__/__helpers/makeStore.ts b/packages/react-headless/src/store/__tests__/__helpers/makeStore.ts
index f0d6eb6ee..01f8e6f77 100644
--- a/packages/react-headless/src/store/__tests__/__helpers/makeStore.ts
+++ b/packages/react-headless/src/store/__tests__/__helpers/makeStore.ts
@@ -1,11 +1,10 @@
 import { vi } from "vitest";
 import type { ChatLLM, ChatStorage, ThreadStorage } from "../../../adapters/types";
-import { createChatStore, type CreateChatStoreConfig } from "../../createChatStore";
+import { createChatStore } from "../../createChatStore";
 
 export interface MakeStoreOverrides extends Partial<ThreadStorage> {
   send?: ChatLLM["send"];
   streamProtocol?: ChatLLM["streamProtocol"];
-  onUserMessageAccepted?: CreateChatStoreConfig["onUserMessageAccepted"];
 }
 
 /**
@@ -14,7 +13,7 @@ export interface MakeStoreOverrides extends Partial<ThreadStorage> {
  * overridden gets a vi.fn() mock with a sensible default return.
  */
 export function makeStore(overrides: MakeStoreOverrides = {}) {
-  const { send, streamProtocol, onUserMessageAccepted, ...threadOverrides } = overrides;
+  const { send, streamProtocol, ...threadOverrides } = overrides;
 
   const storage: ChatStorage = {
     thread: {
@@ -36,5 +35,5 @@ export function makeStore(overrides: MakeStoreOverrides = {}) {
     streamProtocol: streamProtocol ?? { parse: async function* () {} },
   };
 
-  return createChatStore({ current: { storage, llm, onUserMessageAccepted } });
+  return createChatStore({ current: { storage, llm } });
 }
diff --git a/packages/react-headless/src/store/__tests__/createChatStore.test.ts b/packages/react-headless/src/store/__tests__/createChatStore.test.ts
index a5afe4ad2..1d28dfbab 100644
--- a/packages/react-headless/src/store/__tests__/createChatStore.test.ts
+++ b/packages/react-headless/src/store/__tests__/createChatStore.test.ts
@@ -307,29 +307,6 @@ describe("createChatStore", () => {
       expect(send).toHaveBeenCalledOnce();
     });
 
-    it("reports the supplied source without exposing message content", async () => {
-      const onUserMessageAccepted = vi.fn();
-      const store = makeStore({ onUserMessageAccepted });
-      store.setState({ selectedThreadId: "t1" });
-
-      await store
-        .getState()
-        .processMessage({ role: "user", content: "private prompt" }, { source: "composer" });
-
-      expect(onUserMessageAccepted).toHaveBeenCalledOnce();
-      expect(onUserMessageAccepted).toHaveBeenCalledWith({ source: "composer" });
-    });
-
-    it("defaults direct calls to the programmatic source", async () => {
-      const onUserMessageAccepted = vi.fn();
-      const store = makeStore({ onUserMessageAccepted });
-      store.setState({ selectedThreadId: "t1" });
-
-      await store.getState().processMessage({ role: "user", content: "hello" });
-
-      expect(onUserMessageAccepted).toHaveBeenCalledWith({ source: "programmatic" });
-    });
-
     it("creates thread when none selected", async () => {
       const newThread = makeThread("t-auto");
       const createThread = vi.fn().mockResolvedValue(newThread);
@@ -349,11 +326,9 @@ describe("createChatStore", () => {
 
     it("no-ops when already running", async () => {
       const send = vi.fn().mockResolvedValue(new Response("", { status: 200 }));
-      const onUserMessageAccepted = vi.fn();
 
       const store = makeStore({
         send,
-        onUserMessageAccepted,
         streamProtocol: { parse: async function* () {} },
       });
       store.setState({ isRunning: true, selectedThreadId: "t1" });
@@ -361,24 +336,6 @@ describe("createChatStore", () => {
       await store.getState().processMessage({ role: "user", content: "hello" });
 
       expect(send).not.toHaveBeenCalled();
-      expect(onUserMessageAccepted).not.toHaveBeenCalled();
-    });
-
-    it("continues processing if the accepted-turn observer throws", async () => {
-      const send = vi.fn().mockResolvedValue(new Response("", { status: 200 }));
-      const store = makeStore({
-        send,
-        onUserMessageAccepted: () => {
-          throw new Error("observer failed");
-        },
-      });
-      store.setState({ selectedThreadId: "t1" });
-
-      await expect(
-        store.getState().processMessage({ role: "user", content: "hello" }),
-      ).resolves.toBeUndefined();
-
-      expect(send).toHaveBeenCalledOnce();
     });
 
     it("sets threadError on failure", async () => {
diff --git a/packages/react-headless/src/store/createChatStore.ts b/packages/react-headless/src/store/createChatStore.ts
index 0b7df9f57..582e05cc6 100644
--- a/packages/react-headless/src/store/createChatStore.ts
+++ b/packages/react-headless/src/store/createChatStore.ts
@@ -3,12 +3,11 @@ import { subscribeWithSelector } from "zustand/middleware";
 import { getResponseErrorMessage } from "../adapters/httpError";
 import type { ChatLLM, ChatStorage } from "../adapters/types";
 import { processStreamedMessage } from "../stream/processStreamedMessage";
-import type { ChatStore, Message, Thread, UserMessage, UserMessageAcceptedEvent } from "./types";
+import type { ChatStore, Message, Thread, UserMessage } from "./types";
 
 export interface CreateChatStoreConfig {
   storage: ChatStorage;
   llm: ChatLLM;
-  onUserMessageAccepted?: (event: UserMessageAcceptedEvent) => void;
 }
 
 const mergeThreadList = (existing: Thread[], incoming: Thread[]): Thread[] =>
@@ -141,7 +140,7 @@ export const createChatStore = (configRef: React.RefObject<CreateChatStoreConfig
 
       // ── Thread Actions ──
 
-      processMessage: async (message, options) => {
+      processMessage: async (message) => {
         const state = get();
         if (state.isRunning) return;
 
@@ -160,14 +159,6 @@ export const createChatStore = (configRef: React.RefObject<CreateChatStoreConfig
         });
         set((s) => ({ messages: [...s.messages, optimisticMessage] }));
 
-        try {
-          configRef.current.onUserMessageAccepted?.({
-            source: options?.source ?? "programmatic",
-          });
-        } catch {
-          // Observers must not prevent an accepted message from being sent.
-        }
-
         abortController.signal.addEventListener("abort", () => {
           set({ _abortController: null, isRunning: false });
         });
diff --git a/packages/react-headless/src/store/types.ts b/packages/react-headless/src/store/types.ts
index 65d6b4d00..4ddc3c870 100644
--- a/packages/react-headless/src/store/types.ts
+++ b/packages/react-headless/src/store/types.ts
@@ -5,18 +5,6 @@ import type { ArtifactRendererConfig } from "./artifactRendererTypes";
 export type { Message, UserMessage } from "../types/message";
 export type CreateMessage = Omit<UserMessage, "id">;
 
-export type UserMessageSource = "composer" | "starter" | "rendered_action" | "programmatic";
-
-export interface ProcessMessageOptions {
-  /** Identifies the UI path that initiated this accepted user turn. */
-  source?: UserMessageSource;
-}
-
-export interface UserMessageAcceptedEvent {
-  /** The initiating UI path. Message content is intentionally not exposed. */
-  source: UserMessageSource;
-}
-
 export type Thread = {
   id: string;
   title: string;
@@ -63,7 +51,7 @@ export type ThreadState = {
 };
 
 export type ThreadActions = {
-  processMessage: (message: CreateMessage, options?: ProcessMessageOptions) => Promise<void>;
+  processMessage: (message: CreateMessage) => Promise<void>;
   appendMessages: (...messages: Message[]) => void;
   updateMessage: (message: Message) => void;
   setMessages: (messages: Message[]) => void;
@@ -103,11 +91,5 @@ export interface ChatProviderProps {
    * artifact browser's pre-applied filters, and workspace section grouping.
    */
   artifactCategories?: ArtifactCategory[];
-  /**
-   * Called once after a user turn is accepted for processing. Rejected turns
-   * (for example, while another turn is running) do not trigger the callback.
-   * The event intentionally excludes message content.
-   */
-  onUserMessageAccepted?: (event: UserMessageAcceptedEvent) => void;
   children: React.ReactNode;
 }
diff --git a/packages/react-ui/src/components/AgentInterface/AgentInterface.tsx b/packages/react-ui/src/components/AgentInterface/AgentInterface.tsx
index 19e32e8b0..cb90cd7b9 100644
--- a/packages/react-ui/src/components/AgentInterface/AgentInterface.tsx
+++ b/packages/react-ui/src/components/AgentInterface/AgentInterface.tsx
@@ -183,7 +183,6 @@ export const AgentInterface: AgentInterfaceComponent = ((props: AgentInterfacePr
     llm,
     artifactRenderers,
     artifactCategories,
-    onUserMessageAccepted,
     componentLibrary,
     components,
     theme,
@@ -241,7 +240,6 @@ export const AgentInterface: AgentInterfaceComponent = ((props: AgentInterfacePr
         llm={llm}
         artifactRenderers={artifactRenderers}
         artifactCategories={artifactCategories}
-        onUserMessageAccepted={onUserMessageAccepted}
       >
         <NavProvider path={path} defaultPath={defaultPath} onNavigate={onNavigate}>
           <StartersProvider starters={starters} starterVariant={starterVariant}>
diff --git a/packages/react-ui/src/components/AgentInterface/ConversationStarter.tsx b/packages/react-ui/src/components/AgentInterface/ConversationStarter.tsx
index 899ac2b62..0c3782b5d 100644
--- a/packages/react-ui/src/components/AgentInterface/ConversationStarter.tsx
+++ b/packages/react-ui/src/components/AgentInterface/ConversationStarter.tsx
@@ -111,13 +111,10 @@ export const ConversationStarter = ({
       onSelect(starter);
       return;
     }
-    processMessage(
-      {
-        role: "user",
-        content: starter.prompt,
-      },
-      { source: "starter" },
-    );
+    processMessage({
+      role: "user",
+      content: starter.prompt,
+    });
   };
 
   // Only show when there are no messages
diff --git a/packages/react-ui/src/components/AgentInterface/README.md b/packages/react-ui/src/components/AgentInterface/README.md
index be1c1fdc8..2bad376c9 100644
--- a/packages/react-ui/src/components/AgentInterface/README.md
+++ b/packages/react-ui/src/components/AgentInterface/README.md
@@ -156,15 +156,14 @@ Defined as `AgentInterfaceProps` in `AgentInterface.tsx`. It `extends Omit<ChatP
 
 **Forwarded to `ChatProvider`** (from `@openuidev/react-headless`):
 
-| Prop                    | Type                                             | Notes                                                                                                |
-| ----------------------- | ------------------------------------------------ | ---------------------------------------------------------------------------------------------------- |
-| `storage`               | `ChatStorage`                                    | Thread persistence (`listThreads`, `getMessages`, …) and optional `artifact` storage for the browser |
-| `llm`                   | LLM transport                                    | The streaming send adapter                                                                           |
-| `artifactRenderers`     | `AppRenderer[]`                                  | Tool-name → renderer (`parser`/`preview`/`actual`); drives inline previews + detailed view           |
-| `artifactCategories`    | `{ name; filter: { type: string[] } }[]`         | Splits the artifact browser & workspace into sections                                                |
-| `onUserMessageAccepted` | `(event: { source: UserMessageSource }) => void` | Observes accepted user turns without exposing message content                                        |
-
-> ⚠️ Only those five `ChatProviderProps` are actually forwarded (they're destructured explicitly in
+| Prop                 | Type                                     | Notes                                                                                                |
+| -------------------- | ---------------------------------------- | ---------------------------------------------------------------------------------------------------- |
+| `storage`            | `ChatStorage`                            | Thread persistence (`listThreads`, `getMessages`, …) and optional `artifact` storage for the browser |
+| `llm`                | LLM transport                            | The streaming send adapter                                                                           |
+| `artifactRenderers`  | `AppRenderer[]`                          | Tool-name → renderer (`parser`/`preview`/`actual`); drives inline previews + detailed view           |
+| `artifactCategories` | `{ name; filter: { type: string[] } }[]` | Splits the artifact browser & workspace into sections                                                |
+
+> ⚠️ Only those four `ChatProviderProps` are actually forwarded (they're destructured explicitly in
 > `AgentInterface.tsx`). Other `ChatProviderProps` are accepted by the _type_ but not passed through.
 
 **AgentInterface-specific:**
diff --git a/packages/react-ui/src/components/AgentInterface/components/Composer.tsx b/packages/react-ui/src/components/AgentInterface/components/Composer.tsx
index dcc95926c..1aa51fdfd 100644
--- a/packages/react-ui/src/components/AgentInterface/components/Composer.tsx
+++ b/packages/react-ui/src/components/AgentInterface/components/Composer.tsx
@@ -44,13 +44,10 @@ export const Composer = ({ className, placeholder = "Type your query here" }: Co
       return;
     }
 
-    processMessage(
-      {
-        role: "user",
-        content: textContent,
-      },
-      { source: "composer" },
-    );
+    processMessage({
+      role: "user",
+      content: textContent,
+    });
 
     setTextContent("");
   };
diff --git a/packages/react-ui/src/components/AgentInterface/components/DesktopWelcomeComposer.tsx b/packages/react-ui/src/components/AgentInterface/components/DesktopWelcomeComposer.tsx
index 5a20c4393..683e4c621 100644
--- a/packages/react-ui/src/components/AgentInterface/components/DesktopWelcomeComposer.tsx
+++ b/packages/react-ui/src/components/AgentInterface/components/DesktopWelcomeComposer.tsx
@@ -58,13 +58,10 @@ export const DesktopWelcomeComposer = ({
       return;
     }
 
-    processMessage(
-      {
-        role: "user",
-        content: textContent,
-      },
-      { source: "composer" },
-    );
+    processMessage({
+      role: "user",
+      content: textContent,
+    });
 
     setTextContent("");
   };
diff --git a/packages/react-ui/src/components/OpenUIChat/CustomComposerAdapter.tsx b/packages/react-ui/src/components/OpenUIChat/CustomComposerAdapter.tsx
index 29e22880b..d89a3f48b 100644
--- a/packages/react-ui/src/components/OpenUIChat/CustomComposerAdapter.tsx
+++ b/packages/react-ui/src/components/OpenUIChat/CustomComposerAdapter.tsx
@@ -10,7 +10,7 @@ export const CustomComposerAdapter = ({ composer: Composer }: { composer: Compos
   return (
     <Composer
       onSend={(message: string) => {
-        processMessage({ role: "user", content: message }, { source: "composer" });
+        processMessage({ role: "user", content: message });
       }}
       onCancel={cancelMessage}
       isRunning={isRunning}
diff --git a/packages/react-ui/src/components/OpenUIChat/GenUIAssistantMessage.tsx b/packages/react-ui/src/components/OpenUIChat/GenUIAssistantMessage.tsx
index f6416a9c9..1bd95c6c3 100644
--- a/packages/react-ui/src/components/OpenUIChat/GenUIAssistantMessage.tsx
+++ b/packages/react-ui/src/components/OpenUIChat/GenUIAssistantMessage.tsx
@@ -108,13 +108,10 @@ export const GenUIAssistantMessage = ({
         const contextPart = wrapContext(JSON.stringify(messageCtx));
         const llmMessage = `${contentPart}${contextPart}`;
 
-        processMessage(
-          {
-            role: "user",
-            content: llmMessage,
-          },
-          { source: "rendered_action" },
-        );
+        processMessage({
+          role: "user",
+          content: llmMessage,
+        });
       } else if (event.type === BuiltinActionType.OpenUrl) {
         const url = event.params?.["url"] as string | undefined;
         if (typeof window !== "undefined" && url) {
diff --git a/packages/react-ui/src/components/OpenUIChat/withChatProvider.tsx b/packages/react-ui/src/components/OpenUIChat/withChatProvider.tsx
index 23afe00c9..ab216af63 100644
--- a/packages/react-ui/src/components/OpenUIChat/withChatProvider.tsx
+++ b/packages/react-ui/src/components/OpenUIChat/withChatProvider.tsx
@@ -26,7 +26,6 @@ export function withChatProvider<ExtraProps = {}>(WrappedComponent: React.Compon
       llm,
       artifactRenderers,
       artifactCategories,
-      onUserMessageAccepted,
       theme,
       disableThemeProvider,
       ...innerProps
@@ -66,7 +65,6 @@ export function withChatProvider<ExtraProps = {}>(WrappedComponent: React.Compon
           llm={llm}
           artifactRenderers={artifactRenderers}
           artifactCategories={artifactCategories}
-          onUserMessageAccepted={onUserMessageAccepted}
         >
           <WrappedComponent {...finalInnerProps} />
         </ChatProvider>

From 8b8548ef8d5b0e295ea9a522094faabdce07975b Mon Sep 17 00:00:00 2001
From: zahlekhan <zahle@thesys.dev>
Date: Thu, 30 Jul 2026 19:39:29 +0530
Subject: [PATCH 4/5] test(docs): remove link attribution coverage

---
 docs/lib/thesys-link-attribution.test.ts | 53 ------------------------
 1 file changed, 53 deletions(-)
 delete mode 100644 docs/lib/thesys-link-attribution.test.ts

diff --git a/docs/lib/thesys-link-attribution.test.ts b/docs/lib/thesys-link-attribution.test.ts
deleted file mode 100644
index c713f7b32..000000000
--- a/docs/lib/thesys-link-attribution.test.ts
+++ /dev/null
@@ -1,53 +0,0 @@
-import { describe, expect, it } from "vitest";
-import {
-  addThesysLinkAttribution,
-  POSTHOG_DISTINCT_ID_PARAM,
-  POSTHOG_SESSION_ID_PARAM,
-} from "./thesys-link-attribution";
-
-describe("addThesysLinkAttribution", () => {
-  it("forwards anonymous PostHog identity to a Thesys console link", () => {
-    const attributed = new URL(
-      addThesysLinkAttribution(
-        "https://console.thesys.dev/keys?ref=docs#api",
-        "https://openui.com/demo/github",
-        "019b0630-3100-7d69-8ee9-99b639e6474a",
-        "019b0631-3100-7d69-8ee9-99b639e6474b",
-      ),
-    );
-
-    expect(attributed.pathname).toBe("/keys");
-    expect(attributed.searchParams.get("ref")).toBe("docs");
-    expect(attributed.searchParams.get("utm_source")).toBe("openui");
-    expect(attributed.searchParams.get("utm_medium")).toBe("referral");
-    expect(attributed.searchParams.get("utm_campaign")).toBe("openui_to_thesys");
-    expect(attributed.searchParams.get(POSTHOG_DISTINCT_ID_PARAM)).toBe(
-      "019b0630-3100-7d69-8ee9-99b639e6474a",
-    );
-    expect(attributed.searchParams.get(POSTHOG_SESSION_ID_PARAM)).toBe(
-      "019b0631-3100-7d69-8ee9-99b639e6474b",
-    );
-    expect(attributed.hash).toBe("#api");
-  });
-
-  it("does not decorate links outside thesys.dev", () => {
-    expect(
-      addThesysLinkAttribution(
-        "https://example.com/?posthog_distinct_id=keep",
-        "https://openui.com",
-        "anonymous-id",
-        "session-id",
-      ),
-    ).toBe("https://example.com/?posthog_distinct_id=keep");
-  });
-
-  it("adds campaign attribution without inventing missing PostHog IDs", () => {
-    const attributed = new URL(
-      addThesysLinkAttribution("https://thesys.dev", "https://openui.com", undefined, undefined),
-    );
-
-    expect(attributed.searchParams.get("utm_source")).toBe("openui");
-    expect(attributed.searchParams.has(POSTHOG_DISTINCT_ID_PARAM)).toBe(false);
-    expect(attributed.searchParams.has(POSTHOG_SESSION_ID_PARAM)).toBe(false);
-  });
-});

From c4601acbe739560d7bd7fddd91f48e588be18f45 Mon Sep 17 00:00:00 2001
From: zahlekhan <zahle@thesys.dev>
Date: Thu, 30 Jul 2026 19:52:28 +0530
Subject: [PATCH 5/5] test(docs): remove analytics test setup

---
 docs/lib/demo-analytics.test.ts | 264 --------------------------------
 docs/package.json               |   4 +-
 pnpm-lock.yaml                  |   3 -
 3 files changed, 1 insertion(+), 270 deletions(-)
 delete mode 100644 docs/lib/demo-analytics.test.ts

diff --git a/docs/lib/demo-analytics.test.ts b/docs/lib/demo-analytics.test.ts
deleted file mode 100644
index e0447774f..000000000
--- a/docs/lib/demo-analytics.test.ts
+++ /dev/null
@@ -1,264 +0,0 @@
-import { afterEach, describe, expect, it, vi } from "vitest";
-import { GITHUB_DEMO_MODEL } from "./demo-models";
-import { DEFAULT_MODEL } from "./openui-cloud/models";
-
-const { capture } = vi.hoisted(() => ({
-  capture: vi.fn(),
-}));
-
-vi.mock("./analytics", () => ({
-  analytics: { capture },
-}));
-
-import {
-  captureDemoAgentInteraction,
-  DEMO_AGENT_INTERACTION_EVENT,
-  getDemoAgentInteractionProperties,
-  getDemoInteractionSourceFromMessages,
-  type DemoAgentInteraction,
-} from "./demo-analytics";
-
-afterEach(() => {
-  capture.mockReset();
-  vi.unstubAllGlobals();
-});
-
-describe("getDemoInteractionSourceFromMessages", () => {
-  const starter = "Build a revenue dashboard";
-
-  it("classifies a matching first user turn as a starter", () => {
-    expect(
-      getDemoInteractionSourceFromMessages([{ role: "user", content: starter }], [starter]),
-    ).toBe("starter");
-  });
-
-  it("classifies the same text later in a thread as composer input", () => {
-    expect(
-      getDemoInteractionSourceFromMessages(
-        [
-          { role: "user", content: "First turn" },
-          { role: "assistant", content: "Response" },
-          { role: "user", content: starter },
-        ],
-        [starter],
-      ),
-    ).toBe("composer");
-  });
-
-  it("classifies the strict OpenUI action context as a rendered action", () => {
-    expect(
-      getDemoInteractionSourceFromMessages([
-        {
-          role: "user",
-          content:
-            ']]>openui:content\nContinue\n]]>openui:context\n["User clicked: Continue",{"choice":"a"}]',
-        },
-      ]),
-    ).toBe("rendered_action");
-  });
-
-  it("does not mistake arbitrary context or malformed content for an action", () => {
-    expect(
-      getDemoInteractionSourceFromMessages([
-        {
-          role: "user",
-          content: 'Prompt\n]]>openui:context\n["Not an action"]',
-        },
-      ]),
-    ).toBe("composer");
-    expect(getDemoInteractionSourceFromMessages([])).toBeNull();
-  });
-});
-
-describe("getDemoAgentInteractionProperties", () => {
-  it("builds the complete bounded event payload", () => {
-    expect(
-      getDemoAgentInteractionProperties({
-        demo: "compare",
-        variant: "markdown",
-        model: DEFAULT_MODEL,
-        interaction_source: "starter",
-      }),
-    ).toEqual({
-      demo: "compare",
-      variant: "markdown",
-      model: DEFAULT_MODEL,
-      interaction_source: "starter",
-    });
-  });
-
-  it("omits absent and unrecognized variants", () => {
-    expect(
-      getDemoAgentInteractionProperties({
-        demo: "github_dashboard",
-        model: GITHUB_DEMO_MODEL,
-        interaction_source: "starter",
-      }),
-    ).toEqual({
-      demo: "github_dashboard",
-      model: GITHUB_DEMO_MODEL,
-      interaction_source: "starter",
-    });
-
-    expect(
-      getDemoAgentInteractionProperties({
-        demo: "openui_vs_json",
-        variant: "a prompt must never become a dimension",
-        model: "openai/gpt-5.2",
-        interaction_source: "composer",
-      }),
-    ).toEqual({
-      demo: "openui_vs_json",
-      model: "openai/gpt-5.2",
-      interaction_source: "composer",
-    });
-  });
-
-  it("allows canonical model identifiers", () => {
-    expect(
-      getDemoAgentInteractionProperties({
-        demo: "openui_chat",
-        variant: "cloud",
-        model: "anthropic/claude-sonnet-5",
-        interaction_source: "composer",
-      }),
-    ).toEqual({
-      demo: "openui_chat",
-      variant: "cloud",
-      model: "anthropic/claude-sonnet-5",
-      interaction_source: "composer",
-    });
-  });
-
-  it("drops variants that belong to a different demo", () => {
-    expect(
-      getDemoAgentInteractionProperties({
-        demo: "compare",
-        variant: "markdown_vs_cloud",
-        model: DEFAULT_MODEL,
-        interaction_source: "composer",
-      }),
-    ).toEqual({
-      demo: "compare",
-      model: DEFAULT_MODEL,
-      interaction_source: "composer",
-    });
-
-    expect(
-      getDemoAgentInteractionProperties({
-        demo: "github_dashboard",
-        variant: "oss",
-        model: GITHUB_DEMO_MODEL,
-        interaction_source: "composer",
-      }),
-    ).toEqual({
-      demo: "github_dashboard",
-      model: GITHUB_DEMO_MODEL,
-      interaction_source: "composer",
-    });
-  });
-
-  it("does not forward extra or content-bearing fields", () => {
-    const interaction = {
-      demo: "openui_chat",
-      variant: "cloud",
-      model: DEFAULT_MODEL,
-      interaction_source: "rendered_action",
-      prompt: "private prompt",
-      messages: ["private response"],
-      thread_id: "private-thread",
-    } as DemoAgentInteraction & Record<string, unknown>;
-
-    expect(getDemoAgentInteractionProperties(interaction)).toEqual({
-      demo: "openui_chat",
-      variant: "cloud",
-      model: DEFAULT_MODEL,
-      interaction_source: "rendered_action",
-    });
-  });
-
-  it("rejects malformed core dimensions at runtime", () => {
-    expect(getDemoAgentInteractionProperties(null as unknown as DemoAgentInteraction)).toBeNull();
-
-    expect(
-      getDemoAgentInteractionProperties({
-        demo: "unknown",
-        interaction_source: "composer",
-      } as unknown as DemoAgentInteraction),
-    ).toBeNull();
-
-    expect(
-      getDemoAgentInteractionProperties({
-        demo: "compare",
-        model: DEFAULT_MODEL,
-        interaction_source: "click",
-      } as unknown as DemoAgentInteraction),
-    ).toBeNull();
-
-    expect(
-      getDemoAgentInteractionProperties({
-        demo: "github_dashboard",
-        model: DEFAULT_MODEL,
-        interaction_source: "composer",
-      }),
-    ).toBeNull();
-  });
-});
-
-describe("captureDemoAgentInteraction", () => {
-  it("does not capture during server rendering", () => {
-    captureDemoAgentInteraction({
-      demo: "github_dashboard",
-      model: GITHUB_DEMO_MODEL,
-      interaction_source: "composer",
-    });
-
-    expect(capture).not.toHaveBeenCalled();
-  });
-
-  it("captures exactly one allowlisted event in the browser", () => {
-    vi.stubGlobal("window", {});
-
-    captureDemoAgentInteraction({
-      demo: "openui_chat",
-      variant: "oss",
-      model: DEFAULT_MODEL,
-      interaction_source: "starter",
-    });
-
-    expect(capture).toHaveBeenCalledOnce();
-    expect(capture).toHaveBeenCalledWith(DEMO_AGENT_INTERACTION_EVENT, {
-      demo: "openui_chat",
-      variant: "oss",
-      model: DEFAULT_MODEL,
-      interaction_source: "starter",
-    });
-  });
-
-  it("does not capture malformed core dimensions", () => {
-    vi.stubGlobal("window", {});
-
-    captureDemoAgentInteraction({
-      demo: "other",
-      interaction_source: "composer",
-    } as unknown as DemoAgentInteraction);
-
-    expect(capture).not.toHaveBeenCalled();
-  });
-
-  it("does not throw when the analytics client fails synchronously", () => {
-    vi.stubGlobal("window", {});
-    capture.mockImplementationOnce(() => {
-      throw new Error("capture failed");
-    });
-
-    expect(() =>
-      captureDemoAgentInteraction({
-        demo: "compare",
-        variant: "oss",
-        model: DEFAULT_MODEL,
-        interaction_source: "rendered_action",
-      }),
-    ).not.toThrow();
-  });
-});
diff --git a/docs/package.json b/docs/package.json
index ce0a6726e..3f0445aa4 100644
--- a/docs/package.json
+++ b/docs/package.json
@@ -8,7 +8,6 @@
     "build": "next build --no-mangling",
     "dev": "pnpm generate:prompts && next dev",
     "start": "next start",
-    "test": "vitest run",
     "types:check": "fumadocs-mdx && next typegen && tsc --noEmit",
     "postinstall": "fumadocs-mdx",
     "lint": "eslint",
@@ -54,7 +53,6 @@
     "@types/react-dom": "^19.2.3",
     "eslint-config-next": "16.2.6",
     "postcss": "^8.5.6",
-    "tailwindcss": "^4.1.18",
-    "vitest": "^4.1.0"
+    "tailwindcss": "^4.1.18"
   }
 }
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index f9809426c..2a9474cc1 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -179,9 +179,6 @@ importers:
       tailwindcss:
         specifier: ^4.1.18
         version: 4.3.3
-      vitest:
-        specifier: ^4.1.0
-        version: 4.1.10(@opentelemetry/api@1.9.1)(@types/node@22.20.1)(jsdom@26.1.0)(vite@7.3.6(@types/node@22.20.1)(jiti@2.7.0)(lightningcss@1.33.0)(sass@1.102.0)(terser@5.49.0)(tsx@4.23.1)(yaml@2.9.0))
 
   examples/fastapi-backend/frontend:
     dependencies: