diff --git a/packages/core/src/agent/llm-stub.ts b/packages/core/src/agent/llm-stub.ts
index 75d62552..54e96c3c 100644
--- a/packages/core/src/agent/llm-stub.ts
+++ b/packages/core/src/agent/llm-stub.ts
@@ -35,9 +35,29 @@ function lastUserText(context: { messages?: Array<{ role: string; content: unkno
 function alreadyProposed(
   context: { messages?: Array<{ role: string; content: unknown; toolName?: string }> },
 ): boolean {
-  return (context.messages ?? []).some(
-    (m) => m.role === "toolResult" && (m as { toolName?: string }).toolName === "propose_action",
-  );
+  return (context.messages ?? []).some((m) => {
+    // Agent format (non-openai-completions): role="toolResult" with toolName
+    if (m.role === "toolResult" && (m as { toolName?: string }).toolName === "propose_action") {
+      return true;
+    }
+    // LLM format (openai-completions): assistant message with toolCall content
+    if (m.role === "assistant" && Array.isArray(m.content)) {
+      if (
+        (m.content as Array<{ type: string; name?: string }>).some(
+          (c) => c.type === "toolCall" && c.name === "propose_action",
+        )
+      ) {
+        return true;
+      }
+    }
+    // LLM format (openai-completions folded): tool result folded into user message string
+    if (m.role === "user" && typeof m.content === "string") {
+      if (/- propose_action \(/.test(m.content as string)) {
+        return true;
+      }
+    }
+    return false;
+  });
 }
 
 /**
diff --git a/packages/studio/src/__tests__/authoring-confirm-flow.test.ts b/packages/studio/src/__tests__/authoring-confirm-flow.test.ts
new file mode 100644
index 00000000..2a461599
--- /dev/null
+++ b/packages/studio/src/__tests__/authoring-confirm-flow.test.ts
@@ -0,0 +1,74 @@
+import { describe, expect, it, beforeAll, afterAll, beforeEach, afterEach } from "vitest";
+import { mkdtemp, rm, mkdir, writeFile } from "node:fs/promises";
+import { tmpdir } from "node:os";
+import { join } from "node:path";
+import { createStudioServer } from "../api/server.js";
+import { createAndPersistBookSession, loadStoryGraph } from "@actalk/inkos-core";
+
+const INKOS_CONFIG = JSON.stringify({
+  name: "test-project",
+  version: "0.1.0",
+  language: "zh",
+  llm: { model: "test-model", provider: "anthropic" },
+  notify: [],
+});
+
+describe("interactive-film-authoring confirm flow (stubbed LLM)", () => {
+  let root: string;
+  const prev = process.env.INKOS_AGENT_LLM_STUB;
+  beforeAll(() => { process.env.INKOS_AGENT_LLM_STUB = "1"; });
+  afterAll(() => {
+    if (prev === undefined) delete process.env.INKOS_AGENT_LLM_STUB;
+    else process.env.INKOS_AGENT_LLM_STUB = prev;
+  });
+  beforeEach(async () => {
+    root = await mkdtemp(join(tmpdir(), "if-confirm-"));
+    await writeFile(join(root, "inkos.json"), INKOS_CONFIG, "utf-8");
+    await mkdir(join(root, "interactive-films", "p"), { recursive: true });
+  });
+  afterEach(async () => { await rm(root, { recursive: true, force: true }); });
+
+  it("free-text proposes draft_structure, confirm creates the graph", async () => {
+    const app = createStudioServer({} as never, root);
+    const sessionId = "1000000000-test";
+    const bookId = "p";
+
+    // Pre-create the session so the agent endpoint can load it
+    await createAndPersistBookSession(root, bookId, sessionId, "interactive-film-authoring");
+
+    // Step 1: free-text instruction → stubbed agent proposes draft_structure via propose_action
+    const propose = await app.request("/api/v1/agent", {
+      method: "POST",
+      headers: { "Content-Type": "application/json" },
+      body: JSON.stringify({
+        instruction: "帮我搭一个三幕结构",
+        activeBookId: bookId,
+        sessionKind: "interactive-film-authoring",
+        actionSource: "free-text",
+        sessionId,
+      }),
+    });
+    expect(propose.status).toBe(200);
+
+    // Step 2: confirm the proposed action → executeConfirmedProductionAction runs draft_structure
+    // stubChatCompletion returns STRUCTURE_JSON (4 nodes) when prompt mentions "骨架/nodes/结构"
+    const confirm = await app.request("/api/v1/agent", {
+      method: "POST",
+      headers: { "Content-Type": "application/json" },
+      body: JSON.stringify({
+        instruction: "搭建三幕分支结构",
+        activeBookId: bookId,
+        sessionKind: "interactive-film-authoring",
+        actionSource: "button",
+        requestedIntent: "draft_structure",
+        actionPayload: { draftStructure: { instruction: "三幕分支结构", projectId: bookId } },
+        sessionId,
+      }),
+    });
+    expect(confirm.status).toBe(200);
+
+    // Assert the story graph was created with at least 4 nodes
+    const graph = await loadStoryGraph(root, bookId);
+    expect(graph?.nodes.length).toBeGreaterThanOrEqual(4);
+  });
+});
diff --git a/packages/studio/src/api/server.ts b/packages/studio/src/api/server.ts
index 15b17992..67c2e9b5 100644
--- a/packages/studio/src/api/server.ts
+++ b/packages/studio/src/api/server.ts
@@ -3458,7 +3458,7 @@ export function createStudioServer(initialConfig: ProjectConfig, root: string, o
         bookSession = updatedSession;
       }
       let activeBookConfig: { readonly language?: string } | null = null;
-      if (agentBookId) {
+      if (agentBookId && sessionKind !== "interactive-film-authoring") {
         try {
           activeBookConfig = await state.loadBookConfig(agentBookId);
         } catch {