diff --git a/skills/baoyu-image-gen/scripts/main.ts b/skills/baoyu-image-gen/scripts/main.ts
index c07f105..f64b41c 100644
--- a/skills/baoyu-image-gen/scripts/main.ts
+++ b/skills/baoyu-image-gen/scripts/main.ts
@@ -1,6 +1,7 @@
 import path from "node:path";
 import process from "node:process";
 import { homedir } from "node:os";
+import { fileURLToPath } from "node:url";
 import { access, mkdir, readFile, writeFile } from "node:fs/promises";
 import type {
   BatchFile,
@@ -136,7 +137,7 @@ Environment variables:
 Env file load order: CLI args > EXTEND.md > process.env > <cwd>/.baoyu-skills/.env > ~/.baoyu-skills/.env`);
 }
 
-function parseArgs(argv: string[]): CliArgs {
+export function parseArgs(argv: string[]): CliArgs {
   const out: CliArgs = {
     prompt: null,
     promptFiles: [],
@@ -338,12 +339,12 @@ async function loadEnv(): Promise<void> {
   }
 }
 
-function extractYamlFrontMatter(content: string): string | null {
+export function extractYamlFrontMatter(content: string): string | null {
   const match = content.match(/^---\s*\n([\s\S]*?)\n---\s*$/m);
   return match ? match[1] : null;
 }
 
-function parseSimpleYaml(yaml: string): Partial<ExtendConfig> {
+export function parseSimpleYaml(yaml: string): Partial<ExtendConfig> {
   const config: Partial<ExtendConfig> = {};
   const lines = yaml.split("\n");
   let currentKey: string | null = null;
@@ -473,7 +474,7 @@ async function loadExtendConfig(): Promise<Partial<ExtendConfig>> {
   return {};
 }
 
-function mergeConfig(args: CliArgs, extend: Partial<ExtendConfig>): CliArgs {
+export function mergeConfig(args: CliArgs, extend: Partial<ExtendConfig>): CliArgs {
   return {
     ...args,
     provider: args.provider ?? extend.default_provider ?? null,
@@ -483,13 +484,13 @@ function mergeConfig(args: CliArgs, extend: Partial<ExtendConfig>): CliArgs {
   };
 }
 
-function parsePositiveInt(value: string | undefined): number | null {
+export function parsePositiveInt(value: string | undefined): number | null {
   if (!value) return null;
   const parsed = parseInt(value, 10);
   return Number.isFinite(parsed) && parsed > 0 ? parsed : null;
 }
 
-function parsePositiveBatchInt(value: unknown): number | null {
+export function parsePositiveBatchInt(value: unknown): number | null {
   if (value === null || value === undefined) return null;
   if (typeof value === "number") {
     return Number.isInteger(value) && value > 0 ? value : null;
@@ -500,13 +501,13 @@ function parsePositiveBatchInt(value: unknown): number | null {
   return null;
 }
 
-function getConfiguredMaxWorkers(extendConfig: Partial<ExtendConfig>): number {
+export function getConfiguredMaxWorkers(extendConfig: Partial<ExtendConfig>): number {
   const envValue = parsePositiveInt(process.env.BAOYU_IMAGE_GEN_MAX_WORKERS);
   const configValue = extendConfig.batch?.max_workers ?? null;
   return Math.max(1, envValue ?? configValue ?? DEFAULT_MAX_WORKERS);
 }
 
-function getConfiguredProviderRateLimits(
+export function getConfiguredProviderRateLimits(
   extendConfig: Partial<ExtendConfig>
 ): Record<Provider, ProviderRateLimit> {
   const configured: Record<Provider, ProviderRateLimit> = {
@@ -559,14 +560,14 @@ async function readPromptFromStdin(): Promise<string | null> {
   }
 }
 
-function normalizeOutputImagePath(p: string): string {
+export function normalizeOutputImagePath(p: string): string {
   const full = path.resolve(p);
   const ext = path.extname(full);
   if (ext) return full;
   return `${full}.png`;
 }
 
-function detectProvider(args: CliArgs): Provider {
+export function detectProvider(args: CliArgs): Provider {
   if (
     args.referenceImages.length > 0 &&
     args.provider &&
@@ -619,7 +620,7 @@ function detectProvider(args: CliArgs): Provider {
   );
 }
 
-async function validateReferenceImages(referenceImages: string[]): Promise<void> {
+export async function validateReferenceImages(referenceImages: string[]): Promise<void> {
   for (const refPath of referenceImages) {
     const fullPath = path.resolve(refPath);
     try {
@@ -630,7 +631,7 @@ async function validateReferenceImages(referenceImages: string[]): Promise<void>
   }
 }
 
-function isRetryableGenerationError(error: unknown): boolean {
+export function isRetryableGenerationError(error: unknown): boolean {
   const msg = error instanceof Error ? error.message : String(error);
   const nonRetryableMarkers = [
     "Reference image",
@@ -712,7 +713,7 @@ async function prepareSingleTask(args: CliArgs, extendConfig: Partial<ExtendConf
   };
 }
 
-async function loadBatchTasks(batchFilePath: string): Promise<LoadedBatchTasks> {
+export async function loadBatchTasks(batchFilePath: string): Promise<LoadedBatchTasks> {
   const resolvedBatchFilePath = path.resolve(batchFilePath);
   const content = await readFile(resolvedBatchFilePath, "utf8");
   const parsed = JSON.parse(content.replace(/^\uFEFF/, "")) as BatchFile;
@@ -738,11 +739,11 @@ async function loadBatchTasks(batchFilePath: string): Promise<LoadedBatchTasks>
   throw new Error("Invalid batch file. Expected an array of tasks or an object with a tasks array.");
 }
 
-function resolveBatchPath(batchDir: string, filePath: string): string {
+export function resolveBatchPath(batchDir: string, filePath: string): string {
   return path.isAbsolute(filePath) ? filePath : path.resolve(batchDir, filePath);
 }
 
-function createTaskArgs(baseArgs: CliArgs, task: BatchTaskInput, batchDir: string): CliArgs {
+export function createTaskArgs(baseArgs: CliArgs, task: BatchTaskInput, batchDir: string): CliArgs {
   return {
     ...baseArgs,
     prompt: task.prompt ?? null,
@@ -881,7 +882,7 @@ function createProviderGate(providerRateLimits: Record<Provider, ProviderRateLim
   };
 }
 
-function getWorkerCount(taskCount: number, jobs: number | null, maxWorkers: number): number {
+export function getWorkerCount(taskCount: number, jobs: number | null, maxWorkers: number): number {
   const requested = jobs ?? Math.min(taskCount, maxWorkers);
   return Math.max(1, Math.min(requested, taskCount, maxWorkers));
 }
@@ -1011,8 +1012,21 @@ async function main(): Promise<void> {
   await runSingleMode(mergedArgs, extendConfig);
 }
 
-main().catch((error) => {
-  const message = error instanceof Error ? error.message : String(error);
-  console.error(message);
-  process.exit(1);
-});
+function isDirectExecution(metaUrl: string): boolean {
+  const entryPath = process.argv[1];
+  if (!entryPath) return false;
+
+  try {
+    return path.resolve(entryPath) === fileURLToPath(metaUrl);
+  } catch {
+    return false;
+  }
+}
+
+if (isDirectExecution(import.meta.url)) {
+  main().catch((error) => {
+    const message = error instanceof Error ? error.message : String(error);
+    console.error(message);
+    process.exit(1);
+  });
+}
diff --git a/skills/baoyu-image-gen/scripts/providers/dashscope.ts b/skills/baoyu-image-gen/scripts/providers/dashscope.ts
index e59a048..f854e33 100644
--- a/skills/baoyu-image-gen/scripts/providers/dashscope.ts
+++ b/skills/baoyu-image-gen/scripts/providers/dashscope.ts
@@ -13,7 +13,7 @@ function getBaseUrl(): string {
   return base.replace(/\/+$/g, "");
 }
 
-function parseAspectRatio(ar: string): { width: number; height: number } | null {
+export function parseAspectRatio(ar: string): { width: number; height: number } | null {
   const match = ar.match(/^(\d+(?:\.\d+)?):(\d+(?:\.\d+)?)$/);
   if (!match) return null;
   const w = parseFloat(match[1]!);
@@ -45,7 +45,7 @@ const STANDARD_SIZES_2K: [number, number][] = [
   [2048, 2048],
 ];
 
-function getSizeFromAspectRatio(ar: string | null, quality: CliArgs["quality"]): string {
+export function getSizeFromAspectRatio(ar: string | null, quality: CliArgs["quality"]): string {
   const is2k = quality === "2k";
   const defaultSize = is2k ? "1536*1536" : "1024*1024";
 
@@ -71,7 +71,7 @@ function getSizeFromAspectRatio(ar: string | null, quality: CliArgs["quality"]):
   return best;
 }
 
-function normalizeSize(size: string): string {
+export function normalizeSize(size: string): string {
   return size.replace("x", "*");
 }
 
diff --git a/skills/baoyu-image-gen/scripts/providers/google.ts b/skills/baoyu-image-gen/scripts/providers/google.ts
index a3649f0..09985d4 100644
--- a/skills/baoyu-image-gen/scripts/providers/google.ts
+++ b/skills/baoyu-image-gen/scripts/providers/google.ts
@@ -17,16 +17,16 @@ export function getDefaultModel(): string {
   return process.env.GOOGLE_IMAGE_MODEL || "gemini-3-pro-image-preview";
 }
 
-function normalizeGoogleModelId(model: string): string {
+export function normalizeGoogleModelId(model: string): string {
   return model.startsWith("models/") ? model.slice("models/".length) : model;
 }
 
-function isGoogleMultimodal(model: string): boolean {
+export function isGoogleMultimodal(model: string): boolean {
   const normalized = normalizeGoogleModelId(model);
   return GOOGLE_MULTIMODAL_MODELS.some((m) => normalized.includes(m));
 }
 
-function isGoogleImagen(model: string): boolean {
+export function isGoogleImagen(model: string): boolean {
   const normalized = normalizeGoogleModelId(model);
   return GOOGLE_IMAGEN_MODELS.some((m) => normalized.includes(m));
 }
@@ -35,7 +35,7 @@ function getGoogleApiKey(): string | null {
   return process.env.GOOGLE_API_KEY || process.env.GEMINI_API_KEY || null;
 }
 
-function getGoogleImageSize(args: CliArgs): "1K" | "2K" | "4K" {
+export function getGoogleImageSize(args: CliArgs): "1K" | "2K" | "4K" {
   if (args.imageSize) return args.imageSize as "1K" | "2K" | "4K";
   return args.quality === "2k" ? "2K" : "1K";
 }
@@ -46,7 +46,7 @@ function getGoogleBaseUrl(): string {
   return base.replace(/\/+$/g, "");
 }
 
-function buildGoogleUrl(pathname: string): string {
+export function buildGoogleUrl(pathname: string): string {
   const base = getGoogleBaseUrl();
   const cleanedPath = pathname.replace(/^\/+/g, "");
   if (base.endsWith("/v1beta")) return `${base}/${cleanedPath}`;
@@ -162,7 +162,7 @@ async function postGoogleJson<T>(pathname: string, body: unknown): Promise<T> {
   return postGoogleJsonViaFetch<T>(url, apiKey, body);
 }
 
-function buildPromptWithAspect(
+export function buildPromptWithAspect(
   prompt: string,
   ar: string | null,
   quality: CliArgs["quality"],
@@ -177,7 +177,7 @@ function buildPromptWithAspect(
   return result;
 }
 
-function addAspectRatioToPrompt(prompt: string, ar: string | null): string {
+export function addAspectRatioToPrompt(prompt: string, ar: string | null): string {
   if (!ar) return prompt;
   return `${prompt} Aspect ratio: ${ar}.`;
 }
@@ -194,7 +194,7 @@ async function readImageAsBase64(
   return { data: buf.toString("base64"), mimeType };
 }
 
-function extractInlineImageData(response: {
+export function extractInlineImageData(response: {
   candidates?: Array<{
     content?: { parts?: Array<{ inlineData?: { data?: string } }> };
   }>;
@@ -208,7 +208,7 @@ function extractInlineImageData(response: {
   return null;
 }
 
-function extractPredictedImageData(response: {
+export function extractPredictedImageData(response: {
   predictions?: Array<any>;
   generatedImages?: Array<any>;
 }): string | null {
diff --git a/skills/baoyu-image-gen/scripts/providers/openai.ts b/skills/baoyu-image-gen/scripts/providers/openai.ts
index 73f6eab..875631d 100644
--- a/skills/baoyu-image-gen/scripts/providers/openai.ts
+++ b/skills/baoyu-image-gen/scripts/providers/openai.ts
@@ -8,7 +8,7 @@ export function getDefaultModel(): string {
 
 type OpenAIImageResponse = { data: Array<{ url?: string; b64_json?: string }> };
 
-function parseAspectRatio(ar: string): { width: number; height: number } | null {
+export function parseAspectRatio(ar: string): { width: number; height: number } | null {
   const match = ar.match(/^(\d+(?:\.\d+)?):(\d+(?:\.\d+)?)$/);
   if (!match) return null;
   const w = parseFloat(match[1]!);
@@ -23,7 +23,7 @@ type SizeMapping = {
   portrait: string;
 };
 
-function getOpenAISize(
+export function getOpenAISize(
   model: string,
   ar: string | null,
   quality: CliArgs["quality"]
@@ -201,7 +201,7 @@ async function generateWithOpenAIEdits(
   return extractImageFromResponse(result);
 }
 
-function getMimeType(filename: string): string {
+export function getMimeType(filename: string): string {
   const ext = path.extname(filename).toLowerCase();
   if (ext === ".jpg" || ext === ".jpeg") return "image/jpeg";
   if (ext === ".webp") return "image/webp";
@@ -209,7 +209,7 @@ function getMimeType(filename: string): string {
   return "image/png";
 }
 
-async function extractImageFromResponse(result: OpenAIImageResponse): Promise<Uint8Array> {
+export async function extractImageFromResponse(result: OpenAIImageResponse): Promise<Uint8Array> {
   const img = result.data[0];
 
   if (img?.b64_json) {
diff --git a/skills/baoyu-image-gen/scripts/providers/replicate.ts b/skills/baoyu-image-gen/scripts/providers/replicate.ts
index e829c23..611d24e 100644
--- a/skills/baoyu-image-gen/scripts/providers/replicate.ts
+++ b/skills/baoyu-image-gen/scripts/providers/replicate.ts
@@ -20,7 +20,7 @@ function getBaseUrl(): string {
   return base.replace(/\/+$/g, "");
 }
 
-function parseModelId(model: string): { owner: string; name: string; version: string | null } {
+export function parseModelId(model: string): { owner: string; name: string; version: string | null } {
   const [ownerName, version] = model.split(":");
   const parts = ownerName!.split("/");
   if (parts.length !== 2 || !parts[0] || !parts[1]) {
@@ -31,7 +31,7 @@ function parseModelId(model: string): { owner: string; name: string; version: st
   return { owner: parts[0], name: parts[1], version: version || null };
 }
 
-function buildInput(prompt: string, args: CliArgs, referenceImages: string[]): Record<string, unknown> {
+export function buildInput(prompt: string, args: CliArgs, referenceImages: string[]): Record<string, unknown> {
   const input: Record<string, unknown> = { prompt };
 
   if (args.aspectRatio) {
@@ -144,7 +144,7 @@ async function pollPrediction(apiToken: string, getUrl: string): Promise<Predict
   throw new Error(`Replicate prediction timed out after ${MAX_POLL_MS / 1000}s`);
 }
 
-function extractOutputUrl(prediction: PredictionResponse): string {
+export function extractOutputUrl(prediction: PredictionResponse): string {
   const output = prediction.output;
 
   if (typeof output === "string") return output;