diff --git a/tests/test_app.py b/tests/test_app.py
index 4651d37..b9d92d9 100644
--- a/tests/test_app.py
+++ b/tests/test_app.py
@@ -1,9 +1,11 @@
 """test titiler-cmr app."""
 
 import io
+from copy import deepcopy
 from typing import Tuple
 
 import pytest
+from fastapi.testclient import TestClient
 from httpx import Response
 from PIL import Image
 from rasterio.errors import NotGeoreferencedWarning
@@ -187,7 +189,6 @@ def test_xarray_statistics(
         params=xarray_query_params,
         json=arctic_geojson,
     )
-
     assert response.status_code == 200
     assert response.headers["content-type"] == "application/geo+json"
     resp = response.json()
@@ -254,7 +255,7 @@ def test_xarray_part(
 
 
 def test_timeseries_statistics(
-    app,
+    app: TestClient,
     mocker,
     mock_cmr_get_assets,
     xarray_query_params,
@@ -266,7 +267,7 @@ def test_timeseries_statistics(
     we need to catch those requests and mock a response since we can't forward them to
     the test client.
     """
-    arctic_stats = arctic_geojson.copy()
+    arctic_stats = deepcopy(arctic_geojson)
     arctic_stats["properties"]["statistics"] = {
         "sea_ice_fraction": {
             "min": 0,
@@ -292,7 +293,7 @@ async def mock_timestep_request(url: str, **kwargs) -> Response:
         },
         json=arctic_geojson,
     )
-
+    print(response.text)
     assert response.status_code == 200
     assert response.headers["content-type"] == "application/geo+json"
 
diff --git a/titiler/cmr/timeseries.py b/titiler/cmr/timeseries.py
index 84a4f22..f8f261e 100644
--- a/titiler/cmr/timeseries.py
+++ b/titiler/cmr/timeseries.py
@@ -7,7 +7,7 @@
 from datetime import datetime, timedelta
 from enum import Enum
 from types import DynamicClassAttribute
-from typing import Annotated, Any, Dict, List, Literal, Optional, Tuple
+from typing import Annotated, Any, Dict, List, Literal, Optional, Tuple, Union
 from urllib.parse import urlencode
 
 import earthaccess
@@ -17,7 +17,7 @@
 from fastapi import Body, Depends, Path, Query, Request, Response
 from fastapi.exceptions import HTTPException
 from fastapi.responses import StreamingResponse
-from geojson_pydantic import Feature
+from geojson_pydantic import Feature, FeatureCollection
 from PIL import Image
 from pydantic import BaseModel
 
@@ -26,6 +26,7 @@
 from titiler.core.algorithm import algorithms as available_algorithms
 from titiler.core.dependencies import CoordCRSParams, DefaultDependency, DstCRSParams
 from titiler.core.factory import FactoryExtension
+from titiler.core.models.responses import MultiBaseStatisticsGeoJSON
 from titiler.core.resources.enums import ImageType
 from titiler.core.resources.responses import GeoJSONResponse
 
@@ -227,7 +228,7 @@ def timeseries_query(
     else:
         raise HTTPException(
             status_code=400,
-            detail="you must provide start_datetime, end_datetime, and step",
+            detail="you must provide at least start_datetime and end_datetime",
         )
 
     return [
@@ -279,6 +280,7 @@ def register_statistics(self, factory: Endpoints):
 
         @factory.router.post(
             "/timeseries/statistics",
+            response_model=MultiBaseStatisticsGeoJSON,
             response_model_exclude_none=True,
             response_class=GeoJSONResponse,
             responses={
@@ -292,8 +294,8 @@ def register_statistics(self, factory: Endpoints):
         async def timeseries_geojson_statistics(
             request: Request,
             geojson: Annotated[
-                Feature,
-                Body(description="GeoJSON Feature or FeatureCollection."),
+                Union[FeatureCollection, Feature],
+                Body(description="GeoJSON Feature or FeatureCollection.", embed=False),
             ],
             query=Depends(timeseries_query),
             coord_crs=Depends(CoordCRSParams),