diff --git a/src/__tests__/trajectory/trajectory.test.ts b/src/__tests__/trajectory/trajectory.test.ts
index 1df178d..c4f953e 100644
--- a/src/__tests__/trajectory/trajectory.test.ts
+++ b/src/__tests__/trajectory/trajectory.test.ts
@@ -2,19 +2,19 @@
 //
 // 用临时目录构造 session jsonl, 跑 collect → export 三格式, 校验输出结构。
 
-import { describe, expect, it, beforeEach, afterEach } from "bun:test";
+import { afterEach, beforeEach, describe, expect, it } from "bun:test";
 import { promises as fs } from "node:fs";
-import path from "node:path";
 import os from "node:os";
+import path from "node:path";
 import {
 	collectTrajectories,
 	readManifest,
 } from "../../services/trajectory/collector.js";
 import {
+	buildDPOPairs,
 	exportTrajectories,
-	toSFTSample,
 	toGRPOSample,
-	buildDPOPairs,
+	toSFTSample,
 } from "../../services/trajectory/exporters.js";
 import type {
 	CollectedTrajectory,
@@ -265,6 +265,30 @@ describe("exportTrajectories", () => {
 		const rewards = out.map((l) => JSON.parse(l).reward as number).sort();
 		expect(rewards).toEqual([0, 1]);
 	});
+
+	// 回归 #58: sourceDir 指向 session 源目录 (无 manifest), destDir 指向汇聚库
+	// 应通过 destDir 回退定位 manifest, 不再返回 count=0
+	it("#58 export falls back to destDir when sourceDir has no manifest", async () => {
+		await seedTwoSessions();
+		const res = await exportTrajectories({
+			sourceDir, // session 源目录 (无 manifest)
+			destDir, // 汇聚库 (有 manifest)
+			format: "grpo",
+		});
+		expect(res.count).toBe(2); // 不再是 0
+	});
+
+	// 显式 storeDir 优先
+	it("export uses storeDir when provided", async () => {
+		await seedTwoSessions();
+		const res = await exportTrajectories({
+			sourceDir, // 无 manifest, 不应被使用
+			destDir, // 输出目录
+			storeDir: destDir, // 汇聚库
+			format: "sft",
+		});
+		expect(res.count).toBe(1);
+	});
 });
 
 describe("exporter unit transforms", () => {
diff --git a/src/cli/handlers/trajectory.ts b/src/cli/handlers/trajectory.ts
index d8653bc..d953c42 100644
--- a/src/cli/handlers/trajectory.ts
+++ b/src/cli/handlers/trajectory.ts
@@ -10,10 +10,10 @@
 
 import {
 	collectTrajectories,
-	exportTrajectories,
-	readManifest,
 	DEFAULT_DEST_DIR,
 	DEFAULT_SOURCE_DIR,
+	exportTrajectories,
+	readManifest,
 } from "../../services/trajectory/index.js";
 
 interface ParsedFlags {
diff --git a/src/entrypoints/cli.tsx b/src/entrypoints/cli.tsx
index 101d4fd..f0423db 100644
--- a/src/entrypoints/cli.tsx
+++ b/src/entrypoints/cli.tsx
@@ -301,9 +301,7 @@ async function main(): Promise<void> {
 	// 收集 session jsonl → 汇聚标注 → 导出 SFT/DPO/GRPO 训练集。
 	if (args[0] === "trajectory") {
 		profileCheckpoint("cli_trajectory_path");
-		const { trajectoryMain } = await import(
-			"../cli/handlers/trajectory.js"
-		);
+		const { trajectoryMain } = await import("../cli/handlers/trajectory.js");
 		await trajectoryMain(args.slice(1));
 		gracefulShutdownSync(0);
 	}
diff --git a/src/services/trajectory/exporters.ts b/src/services/trajectory/exporters.ts
index 8bd4024..90e21db 100644
--- a/src/services/trajectory/exporters.ts
+++ b/src/services/trajectory/exporters.ts
@@ -133,14 +133,30 @@ export function buildDPOPairs(trajectories: CollectedTrajectory[]): DPOPair[] {
 	return pairs;
 }
 
+// 在候选目录中找到第一个含 manifest.json 的, 返回 {storeDir, manifest}; 都没有则 null
+async function resolveStore(
+	candidates: string[],
+): Promise<{
+	storeDir: string;
+	manifest: NonNullable<Awaited<ReturnType<typeof readManifest>>>;
+} | null> {
+	for (const dir of candidates) {
+		if (!dir) continue;
+		const m = await readManifest(dir);
+		if (m) return { storeDir: dir, manifest: m };
+	}
+	return null;
+}
+
 // 加载所有汇聚轨迹 (或按 sessionId 过滤)
+// storeDir = 汇聚库目录 (manifest.json + raw/ 所在)
 export async function loadAll(
-	destDir: string,
+	storeDir: string,
 	sessionId?: string,
 ): Promise<CollectedTrajectory[]> {
-	const manifest = await readManifest(destDir);
+	const manifest = await readManifest(storeDir);
 	if (!manifest) {
-		log("no manifest at " + destDir + ", run collect first");
+		log("no manifest at " + storeDir + ", run collect first");
 		return [];
 	}
 	const out: CollectedTrajectory[] = [];
@@ -148,7 +164,7 @@ export async function loadAll(
 		if (sessionId && entry.sessionId !== sessionId) continue;
 		const safeName = entry.sessionId.replace(/[^a-zA-Z0-9_-]/g, "_");
 		const rawFile = path.join(
-			destDir,
+			storeDir,
 			"raw",
 			entry.product + "-" + safeName + ".jsonl",
 		);
@@ -168,12 +184,27 @@ async function writeJsonl(filePath: string, records: unknown[]): Promise<void> {
 }
 
 // 主入口
+// 汇聚库定位优先级: storeDir > sourceDir > destDir (取首个含 manifest 者)
 export async function exportTrajectories(
 	options: ExportOptions,
 ): Promise<{ count: number; format: string; destFile: string }> {
-	const { sourceDir, destDir, format, sessionId } = options;
-	log("export format=" + format + " source=" + sourceDir + " dest=" + destDir);
-	const trajectories = await loadAll(sourceDir, sessionId);
+	const { sourceDir, destDir, format, sessionId, storeDir } = options;
+	const resolved = await resolveStore([storeDir, sourceDir, destDir]);
+	if (!resolved) {
+		log(
+			"no manifest found in any of storeDir/sourceDir/destDir " +
+				"(storeDir=" +
+				(storeDir ?? "-") +
+				", sourceDir=" +
+				sourceDir +
+				", destDir=" +
+				destDir +
+				"), run collect first",
+		);
+	}
+	const store = resolved?.storeDir ?? sourceDir ?? destDir;
+	log("export format=" + format + " store=" + store + " dest=" + destDir);
+	const trajectories = await loadAll(store, sessionId);
 	log("loaded " + trajectories.length + " trajectories");
 
 	let records: unknown[] = [];
diff --git a/src/services/trajectory/index.ts b/src/services/trajectory/index.ts
index af2ecac..c19e6ee 100644
--- a/src/services/trajectory/index.ts
+++ b/src/services/trajectory/index.ts
@@ -2,33 +2,33 @@
 
 export {
 	collectTrajectories,
-	readManifest,
-	loadCollectedTrajectory,
-	DEFAULT_SOURCE_DIR,
 	DEFAULT_DEST_DIR,
+	DEFAULT_SOURCE_DIR,
+	loadCollectedTrajectory,
 	MANIFEST_VERSION,
+	readManifest,
 } from "./collector.js";
 
 export {
-	exportTrajectories,
-	toSFTSample,
-	toGRPOSample,
 	buildDPOPairs,
+	exportTrajectories,
 	loadAll,
+	toGRPOSample,
+	toSFTSample,
 } from "./exporters.js";
 
 export type {
+	CollectedTrajectory,
+	CollectOptions,
+	DPOPair,
+	ExportFormat,
+	ExportOptions,
+	GRPOSample,
+	ManifestEntry,
+	SFTSample,
 	ToolCall,
 	ToolResult,
-	TrajectoryStep,
 	TrajectoryLabel,
-	CollectedTrajectory,
-	ManifestEntry,
 	TrajectoryManifest,
-	ExportFormat,
-	SFTSample,
-	DPOPair,
-	GRPOSample,
-	CollectOptions,
-	ExportOptions,
+	TrajectoryStep,
 } from "./types.js";
diff --git a/src/services/trajectory/types.ts b/src/services/trajectory/types.ts
index 823fea8..33b3d2f 100644
--- a/src/services/trajectory/types.ts
+++ b/src/services/trajectory/types.ts
@@ -106,9 +106,13 @@ export interface CollectOptions {
 }
 
 // 导出选项
+// storeDir  = 汇聚库目录 (manifest.json + raw/ 所在), 优先使用
+// sourceDir = 兼容旧调用: 若 storeDir 未传, 作为汇聚库回退
+// destDir   = 输出目录 (sft/dpo/grpo.jsonl 写入处)
 export interface ExportOptions {
 	sourceDir: string;
 	destDir: string;
 	format: ExportFormat;
 	sessionId?: string;
+	storeDir?: string;
 }