diff --git a/frontend/app/composables/usePilotChat.ts b/frontend/app/composables/usePilotChat.ts
index 91dc96d..d6b8dc3 100644
--- a/frontend/app/composables/usePilotChat.ts
+++ b/frontend/app/composables/usePilotChat.ts
@@ -10,7 +10,7 @@ import {
   MeQueryDocument,
 } from "~~/graphql/generated";
 import { Chat as AiChat } from "@ai-sdk/vue";
-import { DefaultChatTransport, isTextUIPart, type DataUIPart, type UIMessage } from "ai";
+import { DefaultChatTransport, isReasoningUIPart, isTextUIPart, type UIMessage } from "ai";
 import { isVoiceCaptureSupported, transcribeAudioBlob } from "~/composables/useVoiceTranscription";
 
 import type { Contact } from "~/composables/useContacts";
@@ -90,30 +90,8 @@ export type ChatConversation = {
   lastMessageText?: string | null;
 };
 
-type PilotDataTypes = {
-  "agent-log": {
-    requestId: string;
-    at: string;
-    text: string;
-  };
-};
-
-type PilotUiMessage = UIMessage<unknown, PilotDataTypes>;
-
 function safeTrim(value: unknown) { return String(value ?? "").trim(); }
-
-function parsePilotAgentLog(part: DataUIPart<PilotDataTypes>) {
-  if (part.type !== "data-agent-log") return null;
-
-  const data = part.data as Partial<PilotDataTypes["agent-log"]> | null | undefined;
-  const text = safeTrim(data?.text);
-  if (!text) return null;
-
-  return {
-    text,
-    at: safeTrim(data?.at) || new Date().toISOString(),
-  };
-}
+type PilotUiMessage = UIMessage;
 
 export function usePilotChat(opts: {
   apolloAuthReady: ComputedRef<boolean>;
@@ -218,11 +196,6 @@ export function usePilotChat(opts: {
     transport: new DefaultChatTransport({
       api: "/api/pilot-chat",
     }),
-    onData: (part) => {
-      const log = parsePilotAgentLog(part);
-      if (!log) return;
-      pilotLiveLogs.value = [...pilotLiveLogs.value, { id: `${Date.now()}-${Math.random()}`, text: log.text, at: log.at }];
-    },
     onFinish: async () => {
       pilotSending.value = false;
       livePilotUserText.value = "";
@@ -274,6 +247,16 @@ export function usePilotChat(opts: {
 
     const textPart = latestAssistant.parts.find(isTextUIPart);
     livePilotAssistantText.value = textPart?.text ?? "";
+
+    // Use native AI SDK reasoning parts for live "thinking" output.
+    pilotLiveLogs.value = latestAssistant.parts
+      .filter(isReasoningUIPart)
+      .map((part, index) => ({
+        id: `${latestAssistant.id}-reasoning-${index}`,
+        text: safeTrim(part.text),
+        at: new Date().toISOString(),
+      }))
+      .filter((log) => Boolean(log.text));
   });
 
   // ---------------------------------------------------------------------------
@@ -309,10 +292,15 @@ export function usePilotChat(opts: {
   // Pilot ↔ UIMessage bridge
   // ---------------------------------------------------------------------------
   function pilotToUiMessage(message: PilotMessage): PilotUiMessage {
+    const reasoningParts = (message.thinking ?? [])
+      .map((item) => safeTrim(item))
+      .filter(Boolean)
+      .map((text) => ({ type: "reasoning" as const, text, state: "done" as const }));
+
     return {
       id: message.id,
       role: message.role,
-      parts: [{ type: "text", text: message.text }],
+      parts: [...reasoningParts, { type: "text", text: message.text }],
       metadata: {
         createdAt: message.createdAt ?? null,
       },
@@ -702,6 +690,7 @@ export function usePilotChat(opts: {
     refetchChatConversations,
     // realtime pilot trace handlers (called from useCrmRealtime)
     handleRealtimePilotTrace(log: { text: string; at: string }) {
+      if (pilotSending.value) return;
       const text = String(log.text ?? "").trim();
       if (!text) return;
       // Mark as sending so the UI shows live-log panel
diff --git a/frontend/server/api/pilot-chat.post.ts b/frontend/server/api/pilot-chat.post.ts
index c16d7a4..fbe8c89 100644
--- a/frontend/server/api/pilot-chat.post.ts
+++ b/frontend/server/api/pilot-chat.post.ts
@@ -15,15 +15,7 @@ import type { ChangeSet } from "../utils/changeSet";
 import { startPilotRun, addPilotTrace, finishPilotRun } from "../utils/pilotRunStore";
 import { broadcastToConversation } from "../routes/ws/crm-updates";
 
-type PilotDataTypes = {
-  "agent-log": {
-    requestId: string;
-    at: string;
-    text: string;
-  };
-};
-
-type PilotUiMessage = UIMessage<unknown, PilotDataTypes>;
+type PilotUiMessage = UIMessage;
 
 type PilotChatRequestBody = {
   messages?: unknown;
@@ -41,7 +33,7 @@ function extractMessageText(message: PilotUiMessage): string {
 function getLastUserText(messages: PilotUiMessage[]): string {
   for (let i = messages.length - 1; i >= 0; i -= 1) {
     const message = messages[i];
-    if (message.role !== "user") continue;
+    if (!message || message.role !== "user") continue;
     const text = extractMessageText(message);
     if (text) return text;
   }
@@ -156,11 +148,10 @@ function renderChangeSetSummary(changeSet: ChangeSet): string {
   return lines.join("\n");
 }
 
-function writePilotLog(writer: UIMessageStreamWriter<PilotUiMessage>, payload: PilotDataTypes["agent-log"]) {
-  writer.write({
-    type: "data-agent-log",
-    data: payload,
-  });
+function writeAssistantReasoning(writer: UIMessageStreamWriter<PilotUiMessage>, reasoningId: string, text: string) {
+  writer.write({ type: "reasoning-start", id: reasoningId });
+  writer.write({ type: "reasoning-delta", id: reasoningId, delta: text });
+  writer.write({ type: "reasoning-end", id: reasoningId });
 }
 
 function writeAssistantText(writer: UIMessageStreamWriter<PilotUiMessage>, textId: string, text: string) {
@@ -229,12 +220,9 @@ export default defineEventHandler(async (event) => {
           onTrace: async (trace: AgentTraceEvent) => {
             const traceText = humanizeTraceText(trace);
             const traceAt = new Date().toISOString();
+            const reasoningId = `reasoning-${Date.now()}-${Math.floor(Math.random() * 1_000_000)}`;
 
-            writePilotLog(writer, {
-              requestId,
-              at: traceAt,
-              text: traceText,
-            });
+            writeAssistantReasoning(writer, reasoningId, traceText);
 
             addPilotTrace(auth.conversationId, traceText);
             broadcastToConversation(auth.conversationId, {
@@ -245,6 +233,16 @@ export default defineEventHandler(async (event) => {
           },
         });
 
+        for (const thought of reply.thinking ?? []) {
+          const text = String(thought ?? "").trim();
+          if (!text) continue;
+          writeAssistantReasoning(
+            writer,
+            `reasoning-${Date.now()}-${Math.floor(Math.random() * 1_000_000)}`,
+            text,
+          );
+        }
+
         const snapshotAfter = await captureSnapshot(prisma, auth.teamId);
         const changeSet = buildChangeSet(snapshotBefore, snapshotAfter);
 
@@ -297,11 +295,11 @@ export default defineEventHandler(async (event) => {
 
         finalizePilotExecution(auth.conversationId, "error");
 
-        writePilotLog(writer, {
-          requestId,
-          at: new Date().toISOString(),
-          text: "Ошибка выполнения агентского цикла.",
-        });
+        writeAssistantReasoning(
+          writer,
+          `reasoning-${Date.now()}-${Math.floor(Math.random() * 1_000_000)}`,
+          "Ошибка выполнения агентского цикла.",
+        );
 
         writeAssistantText(writer, textId, errorText);
         writer.write({ type: "finish", finishReason: "error" });