feat(agent): show PostHog products used below each turn

apps/code/src/renderer/features/sessions/components/SessionResourcesBar.tsx

@@ -0,0 +1,121 @@
+import { CHAT_CONTENT_MAX_WIDTH } from "@features/sessions/constants";
+import type { IconProps } from "@phosphor-icons/react";
+import {
+  BrainIcon,
+  BugIcon,
+  ChartLineIcon,
+  ClipboardTextIcon,
+  CodeIcon,
+  DatabaseIcon,
+  FileTextIcon,
+  FlagIcon,
+  FlaskIcon,
+  GaugeIcon,
+  GlobeIcon,
+  PlugIcon,
+  SparkleIcon,
+  TableIcon,
+  VideoIcon,
+} from "@phosphor-icons/react";
+import type { PostHogProductId } from "@posthog/agent";
+import { Badge, Box, Flex, Text } from "@radix-ui/themes";
+import type { AcpMessage } from "@shared/types/session-events";
+import { openUrlInBrowser } from "@utils/browser";
+import { type ComponentType, useMemo } from "react";
+import { accumulateSessionResources } from "./accumulateSessionResources";
+
+/**
+ * Icon per PostHog product. `Record<PostHogProductId, …>` keeps this exhaustive:
+ * adding a product id in `@posthog/agent` forces an icon here at compile time.
+ */
+const PRODUCT_ICON: Record<PostHogProductId, ComponentType<IconProps>> = {
+  product_analytics: ChartLineIcon,
+  web_analytics: GlobeIcon,
+  feature_flags: FlagIcon,
+  experiments: FlaskIcon,
+  error_tracking: BugIcon,
+  session_replay: VideoIcon,
+  surveys: ClipboardTextIcon,
+  llm_analytics: BrainIcon,
+  data_warehouse: DatabaseIcon,
+  cdp: PlugIcon,
+  logs: FileTextIcon,
+  apm: GaugeIcon,
+  sql: TableIcon,
+  code: CodeIcon,
+  posthog: SparkleIcon,
+};
+
+/**
+ * Docs page on posthog.com per product, so a chip links to the relevant
+ * product docs. `Partial` on purpose — products without a dedicated docs page
+ * (e.g. apm, which PostHog folds into LLM analytics / Logs) render as a plain,
+ * non-clickable badge rather than linking somewhere misleading.
+ */
+const PRODUCT_DOC_URL: Partial<Record<PostHogProductId, string>> = {
+  product_analytics: "https://posthog.com/docs/product-analytics",
+  web_analytics: "https://posthog.com/docs/web-analytics",
+  feature_flags: "https://posthog.com/docs/feature-flags",
+  experiments: "https://posthog.com/docs/experiments",
+  error_tracking: "https://posthog.com/docs/error-tracking",
+  session_replay: "https://posthog.com/docs/session-replay",
+  surveys: "https://posthog.com/docs/surveys",
+  llm_analytics: "https://posthog.com/docs/ai-observability",
+  data_warehouse: "https://posthog.com/docs/data-warehouse",
+  cdp: "https://posthog.com/docs/cdp",
+  logs: "https://posthog.com/docs/logs",
+  sql: "https://posthog.com/docs/sql",
+  code: "https://posthog.com/code",
+  posthog: "https://posthog.com/docs",
+};
+
+interface SessionResourcesBarProps {
+  events: AcpMessage[];
+}
+
+/**
+ * Persistent bar above the composer listing the PostHog products the agent has
+ * touched so far this session — via the MCP `exec` tool, or by reading a file
+ * from the codebase (the "Code" chip). Each product appears once and is added
+ * the moment it's first used. Hidden until at least one product has been used.
+ * Mirrors PlanStatusBar's placement and styling.
+ */
+export function SessionResourcesBar({ events }: SessionResourcesBarProps) {
+  const products = useMemo(() => accumulateSessionResources(events), [events]);
+
+  if (products.length === 0) return null;
+
+  return (
+    <Box className="mb-3">
+      <Box className="mx-auto" style={{ maxWidth: CHAT_CONTENT_MAX_WIDTH }}>
+        <Flex align="center" gap="2" wrap="wrap" className="px-3 pt-2">
+          <Text color="gray" className="whitespace-nowrap text-[12px]">
+            PostHog resources used
+          </Text>
+          {products.map((product) => {
+            const Icon = PRODUCT_ICON[product.id] ?? SparkleIcon;
+            const docUrl = PRODUCT_DOC_URL[product.id];
+            return (
+              <Badge
+                key={product.id}
+                size="1"
+                color="gray"
+                variant="soft"
+                className={
+                  docUrl ? "cursor-pointer hover:bg-gray-4" : undefined
+                }
+                onClick={
+                  docUrl ? () => void openUrlInBrowser(docUrl) : undefined
+                }
+                title={docUrl ? `Open ${product.label} docs` : undefined}
+              >
+                <Icon size={12} />
+                {product.label}
+              </Badge>
+            );
+          })}
+        </Flex>
+      </Box>
+    </Box>
+  );
+}

apps/code/src/renderer/features/sessions/components/SessionView.tsx

@@ -48,6 +48,7 @@ import { PendingChatView } from "./PendingChatView";
 import { PlanStatusBar } from "./PlanStatusBar";
 import { ReasoningLevelSelector } from "./ReasoningLevelSelector";
 import { RawLogsView } from "./raw-logs/RawLogsView";
+import { SessionResourcesBar } from "./SessionResourcesBar";
 
 interface SessionViewProps {
   events: AcpMessage[];
@@ -604,6 +605,8 @@ export function SessionView({
                   compact={compact}
                 />
 
+                <SessionResourcesBar events={events} />
+
                 <PlanStatusBar plan={latestPlan} />
 
                 {hasError && !showInlineBanner ? (

apps/code/src/renderer/features/sessions/components/accumulateSessionResources.test.ts

@@ -0,0 +1,66 @@
+import type { AcpMessage } from "@shared/types/session-events";
+import { describe, expect, it } from "vitest";
+import { accumulateSessionResources } from "./accumulateSessionResources";
+
+function resourcesUsedMsg(
+  ts: number,
+  products: { id: string; label: string }[],
+): AcpMessage {
+  return {
+    type: "acp_message",
+    ts,
+    message: {
+      jsonrpc: "2.0",
+      method: "_posthog/resources_used",
+      params: { sessionId: "session-1", products },
+    },
+  };
+}
+
+describe("accumulateSessionResources", () => {
+  it("collects products across notifications in first-seen order", () => {
+    const events: AcpMessage[] = [
+      resourcesUsedMsg(1, [{ id: "feature_flags", label: "Feature flags" }]),
+      resourcesUsedMsg(2, [
+        { id: "product_analytics", label: "Product analytics" },
+      ]),
+    ];
+
+    expect(accumulateSessionResources(events)).toEqual([
+      { id: "feature_flags", label: "Feature flags" },
+      { id: "product_analytics", label: "Product analytics" },
+    ]);
+  });
+
+  it("de-duplicates a product used across multiple turns", () => {
+    const events: AcpMessage[] = [
+      resourcesUsedMsg(1, [{ id: "feature_flags", label: "Feature flags" }]),
+      resourcesUsedMsg(2, [{ id: "experiments", label: "Experiments" }]),
+      // feature_flags used again on a later turn — must not appear twice.
+      resourcesUsedMsg(3, [{ id: "feature_flags", label: "Feature flags" }]),
+    ];
+
+    const result = accumulateSessionResources(events);
+    expect(result).toEqual([
+      { id: "feature_flags", label: "Feature flags" },
+      { id: "experiments", label: "Experiments" },
+    ]);
+  });
+
+  it("ignores unrelated events and empty payloads", () => {
+    const events: AcpMessage[] = [
+      {
+        type: "acp_message",
+        ts: 1,
+        message: {
+          jsonrpc: "2.0",
+          method: "_posthog/turn_complete",
+          params: { stopReason: "end_turn" },
+        },
+      },
+      resourcesUsedMsg(2, []),
+    ];
+
+    expect(accumulateSessionResources(events)).toEqual([]);
+  });
+});

apps/code/src/renderer/features/sessions/components/accumulateSessionResources.ts

@@ -0,0 +1,44 @@
+import {
+  isNotification,
+  POSTHOG_NOTIFICATIONS,
+  type PostHogProductId,
+} from "@posthog/agent";
+import {
+  type AcpMessage,
+  isJsonRpcNotification,
+} from "@shared/types/session-events";
+
+export interface ResourceProduct {
+  id: PostHogProductId;
+  label: string;
+}
+
+/**
+ * Accumulate the de-duplicated, first-seen-ordered list of PostHog products
+ * used across the whole session, from its `_posthog/resources_used`
+ * notifications. Works for both live streaming and log replay, since both feed
+ * the same `events` array. A product used on several turns appears once.
+ *
+ * Kept in its own module (no React / tRPC imports) so it stays a cheap,
+ * dependency-free unit to test.
+ */
+export function accumulateSessionResources(
+  events: AcpMessage[],
+): ResourceProduct[] {
+  const byId = new Map<PostHogProductId, ResourceProduct>();
+  for (const event of events) {
+    const msg = event.message;
+    if (!isJsonRpcNotification(msg)) continue;
+    if (!isNotification(msg.method, POSTHOG_NOTIFICATIONS.RESOURCES_USED)) {
+      continue;
+    }
+    const products = (
+      msg.params as { products?: ResourceProduct[] } | undefined
+    )?.products;
+    if (!products) continue;
+    for (const product of products) {
+      if (product && !byId.has(product.id)) byId.set(product.id, product);
+    }
+  }
+  return [...byId.values()];
+}

apps/code/src/renderer/features/sessions/components/buildConversationItems.test.ts

@@ -74,6 +74,38 @@ function turnCompleteMsg(ts: number, stopReason = "end_turn"): AcpMessage {
   };
 }
 
+function agentMessageMsg(ts: number, text: string): AcpMessage {
+  return {
+    type: "acp_message",
+    ts,
+    message: {
+      jsonrpc: "2.0",
+      method: "session/update",
+      params: {
+        update: {
+          sessionUpdate: "agent_message_chunk",
+          content: { type: "text", text },
+        },
+      },
+    },
+  };
+}
+
+function resourcesUsedMsg(
+  ts: number,
+  products: { id: string; label: string }[],
+): AcpMessage {
+  return {
+    type: "acp_message",
+    ts,
+    message: {
+      jsonrpc: "2.0",
+      method: "_posthog/resources_used",
+      params: { sessionId: "session-1", products },
+    },
+  };
+}
+
 describe("buildConversationItems", () => {
   it("extracts cloud prompt attachments into user messages", () => {
     const uri = makeAttachmentUri("/tmp/hello world.txt");
@@ -421,6 +453,30 @@ describe("buildConversationItems", () => {
       expect(findProgressGroups(result.items)).toHaveLength(0);
     });
   });
+
+  describe("resources_used", () => {
+    it("does not render an inline item (surfaced in the persistent bar)", () => {
+      const events: AcpMessage[] = [
+        userPromptMsg(1, 1, "list my experiments"),
+        agentMessageMsg(2, "Here are your experiments."),
+        resourcesUsedMsg(3, [{ id: "experiments", label: "Experiments" }]),
+        promptResponseMsg(4, 1),
+      ];
+
+      const result = buildConversationItems(events, false);
+
+      // The notification must not produce any conversation item — it's now
+      // handled out-of-band by SessionResourcesBar / accumulateSessionResources.
+      expect(
+        result.items.some(
+          (i) =>
+            i.type === "session_update" &&
+            // biome-ignore lint/suspicious/noExplicitAny: removed union member
+            (i.update.sessionUpdate as any) === "resources_used",
+        ),
+      ).toBe(false);
+    });
+  });
 });
 
 // Local alias kept intentionally narrow to the shape we care about in tests.

apps/code/src/renderer/features/sessions/components/buildConversationItems.ts

@@ -380,6 +380,10 @@ function handleNotification(
     return;
   }
 
+  // `_posthog/resources_used` is intentionally NOT rendered inline here — the
+  // products are surfaced as a persistent, de-duplicated bar above the composer
+  // (see accumulateSessionResources / SessionResourcesBar).
+
   if (isNotification(msg.method, POSTHOG_NOTIFICATIONS.TURN_COMPLETE)) {
     const params = msg.params as { stopReason?: string } | undefined;
     if (!b.currentTurn) return;

packages/agent/src/acp-extensions.ts

@@ -67,6 +67,9 @@ export const POSTHOG_NOTIFICATIONS = {
   /** Token usage update for a session turn */
   USAGE_UPDATE: "_posthog/usage_update",
 
+  /** PostHog products used during a turn (derived from MCP exec calls) */
+  RESOURCES_USED: "_posthog/resources_used",
+
   /** Response to a relayed permission request (plan approval, question) */
   PERMISSION_RESPONSE: "_posthog/permission_response",
 

packages/agent/src/adapters/claude/claude-agent.refresh.test.ts

@@ -97,6 +97,7 @@ function installFakeSession(
       cachedReadTokens: 0,
       cachedWriteTokens: 0,
     },
+    sessionResources: new Set(),
     configOptions: [],
     promptRunning: false,
     pendingMessages: new Map(),

packages/agent/src/adapters/claude/claude-agent.slash-command.test.ts

@@ -58,6 +58,7 @@ function installFakeSession(
       cachedReadTokens: 0,
       cachedWriteTokens: 0,
     },
+    sessionResources: new Set(),
     configOptions: [],
     promptRunning: false,
     pendingMessages: new Map(),