diff --git a/servers/fastapi/api/lifespan.py b/servers/fastapi/api/lifespan.py
deleted file mode 100644
index 49a9378a..00000000
--- a/servers/fastapi/api/lifespan.py
+++ /dev/null
@@ -1,16 +0,0 @@
-from contextlib import asynccontextmanager
-import os
-
-from fastapi import FastAPI
-from sqlmodel import SQLModel
-
-from services import SQL_ENGINE
-from utils.check_llm_model_availability import check_llm_model_availability
-
-
-@asynccontextmanager
-async def app_lifespan(_: FastAPI):
-    os.makedirs(os.getenv("APP_DATA_DIRECTORY"), exist_ok=True)
-    SQLModel.metadata.create_all(SQL_ENGINE)
-    await check_llm_model_availability()
-    yield
diff --git a/servers/fastapi/api/main.py b/servers/fastapi/api/main.py
index 6d00861b..40589d17 100644
--- a/servers/fastapi/api/main.py
+++ b/servers/fastapi/api/main.py
@@ -1,12 +1,51 @@
-from fastapi import FastAPI
+from contextlib import asynccontextmanager
+import os
+from fastapi import FastAPI, Request
+from fastapi.middleware.cors import CORSMiddleware
 from fastapi.staticfiles import StaticFiles
+from sqlmodel import SQLModel
 from api.v1.ppt.router import API_V1_PPT_ROUTER
-from api.lifespan import app_lifespan
+from services import SQL_ENGINE
+from utils.check_llm_model_availability import check_llm_model_availability
+from utils.get_env import get_can_change_keys_env
+from utils.user_config import update_env_with_user_config
 
 
+# Lifespan
+@asynccontextmanager
+async def app_lifespan(_: FastAPI):
+    os.makedirs(os.getenv("APP_DATA_DIRECTORY"), exist_ok=True)
+    SQLModel.metadata.create_all(SQL_ENGINE)
+    await check_llm_model_availability()
+    yield
+
+
+# App
 APP = FastAPI(lifespan=app_lifespan)
 
+
+# Static files
 APP.mount("/static", StaticFiles(directory="static"), name="static")
 # APP.mount("/static/app-data", StaticFiles(directory=get_app_data_directory_env()))
 
+
+# Routers
 APP.include_router(API_V1_PPT_ROUTER)
+
+
+# Middlewares
+origins = ["*"]
+APP.add_middleware(
+    CORSMiddleware,
+    allow_origins=origins,
+    allow_credentials=True,
+    allow_methods=["*"],
+    allow_headers=["*"],
+)
+
+
+@APP.middleware("http")
+async def update_env_middleware(request: Request, call_next):
+    if get_can_change_keys_env() != "false":
+        update_env_with_user_config()
+    return await call_next(request)
diff --git a/servers/fastapi/api/middlewares.py b/servers/fastapi/api/middlewares.py
deleted file mode 100644
index 8a1bf7a0..00000000
--- a/servers/fastapi/api/middlewares.py
+++ /dev/null
@@ -1,23 +0,0 @@
-from fastapi import Request
-from api.main import APP
-from fastapi.middleware.cors import CORSMiddleware
-
-from utils.get_env import get_can_change_keys_env
-from utils.user_config import update_env_with_user_config
-
-
-origins = ["*"]
-APP.add_middleware(
-    CORSMiddleware,
-    allow_origins=origins,
-    allow_credentials=True,
-    allow_methods=["*"],
-    allow_headers=["*"],
-)
-
-
-@APP.middleware("http")
-async def update_env_middleware(request: Request, call_next):
-    if get_can_change_keys_env() != "false":
-        update_env_with_user_config()
-    return await call_next(request)
diff --git a/servers/fastapi/api/v1/ppt/endpoints/files.py b/servers/fastapi/api/v1/ppt/endpoints/files.py
index c4230604..e2f43329 100644
--- a/servers/fastapi/api/v1/ppt/endpoints/files.py
+++ b/servers/fastapi/api/v1/ppt/endpoints/files.py
@@ -37,7 +37,7 @@ async def upload_files(files: Optional[List[UploadFile]]):
     return temp_files
 
 
-@FILES_ROUTER.post("/decompose")
+@FILES_ROUTER.post("/decompose", response_model=List[DecomposedFileInfo])
 async def decompose_files(file_paths: Annotated[List[str], Body(embed=True)]):
     temp_dir = TEMP_FILE_SERVICE.create_temp_dir(str(uuid.uuid4()))