diff --git a/CHANGES.md b/CHANGES.md
index dfecdc558..bfb6451b1 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -14,6 +14,7 @@
 * add `MultiBaseTilerFactory` and `MultiBandTilerFactory` custom tiler factories (https://github.com/developmentseed/titiler/pull/230)
 * Update STAC tiler to use the new `MultiBaseTilerFactory` factory
 * depreciate *empty* GET endpoint for MosaicTilerFactory read (https://github.com/developmentseed/titiler/pull/232)
+* better `debug` configuration and make reponse headers metadata optional (https://github.com/developmentseed/titiler/pull/232)
 
 **breaking change**
 
diff --git a/tests/routes/test_cog.py b/tests/routes/test_cog.py
index c1963cb5a..f76f41543 100644
--- a/tests/routes/test_cog.py
+++ b/tests/routes/test_cog.py
@@ -129,10 +129,6 @@ def test_tile(rio, app):
     meta = parse_img(response.content)
     assert meta["width"] == 256
     assert meta["height"] == 256
-    timing = response.headers["server-timing"]
-    assert "dataread;dur" in timing
-    assert "postprocess;dur" in timing
-    assert "format;dur" in timing
 
     response = app.get(
         "/cog/tiles/8/87/48@2x?url=https://myurl.com/cog.tif&rescale=0,1000&color_formula=Gamma R 3"
@@ -278,10 +274,6 @@ def test_preview(rio, app):
     assert meta["width"] == 256
     assert meta["height"] == 256
     assert meta["driver"] == "JPEG"
-    timing = response.headers["server-timing"]
-    assert "dataread;dur" in timing
-    assert "postprocess;dur" in timing
-    assert "format;dur" in timing
 
     response = app.get(
         "/cog/preview.png?url=https://myurl.com/cog.tif&rescale=0,1000&max_size=256"
@@ -339,10 +331,6 @@ def test_part(rio, app):
     assert meta["width"] == 256
     assert meta["height"] == 73
     assert meta["driver"] == "PNG"
-    timing = response.headers["server-timing"]
-    assert "dataread;dur" in timing
-    assert "postprocess;dur" in timing
-    assert "format;dur" in timing
 
     response = app.get(
         "/cog/crop/-56.228,72.715,-54.547,73.188.jpg?url=https://myurl.com/cog.tif&rescale=0,1000&max_size=256&return_mask=false"
@@ -394,8 +382,6 @@ def test_point(rio, app):
     assert response.headers["content-type"] == "application/json"
     body = response.json()
     assert body["coordinates"] == [-56.228, 72.715]
-    timing = response.headers["server-timing"]
-    assert "dataread;dur" in timing
 
 
 def test_file_not_found_error(app):
diff --git a/tests/routes/test_mosaic.py b/tests/routes/test_mosaic.py
index 38b0df485..2f4db51de 100644
--- a/tests/routes/test_mosaic.py
+++ b/tests/routes/test_mosaic.py
@@ -105,10 +105,6 @@ def test_point(app):
     assert len(body["values"]) == 1
     assert body["values"][0][0].endswith(".tif")
     assert body["values"][0][1] == [9943, 9127, 9603]
-    timing = response.headers["server-timing"]
-    assert "mosaicread;dur" in timing
-    assert "dataread;dur" in timing
-    assert "total;dur" in timing
 
 
 def test_tile(app):
@@ -126,15 +122,8 @@ def test_tile(app):
         )
         assert response.status_code == 200
         assert response.headers["content-type"] == "image/png"
-        assert response.headers["X-Assets"]
         meta = parse_img(response.content)
         assert meta["width"] == meta["height"] == 256
-        timing = response.headers["server-timing"]
-        assert "mosaicread;dur" in timing
-        assert "dataread;dur" in timing
-        assert "postprocess;dur" in timing
-        assert "format;dur" in timing
-        assert "total;dur" in timing
 
         response = app.get(
             f"/mosaicjson/tiles/{tile.z}/{tile.x}/{tile.y}@2x",
diff --git a/tests/test_factories.py b/tests/test_factories.py
index a69cef148..ce4c455a9 100644
--- a/tests/test_factories.py
+++ b/tests/test_factories.py
@@ -1,26 +1,117 @@
 # """Test TiTiler Tiler Factories."""
 
-from rio_tiler.io import COGReader
+import os
+import tempfile
+from contextlib import contextmanager
 
+from cogeo_mosaic.backends import FileBackend
+from cogeo_mosaic.mosaic import MosaicJSON
 
-def test_TilerFactory(set_env):
+from titiler.dependencies import TMSParams, WebMercatorTMSParams
+from titiler.endpoints import factory
+from titiler.resources.enums import OptionalHeaders
+
+from .conftest import DATA_DIR
+
+from fastapi import FastAPI
+
+from starlette.testclient import TestClient
+
+assets = [os.path.join(DATA_DIR, asset) for asset in ["cog1.tif", "cog2.tif"]]
+
+
+def test_TilerFactory():
     """Test TilerFactory class."""
-    from titiler.dependencies import TMSParams
-    from titiler.endpoints import factory
+    cog = factory.TilerFactory()
+    assert len(cog.router.routes) == 21
+    assert cog.tms_dependency == TMSParams
+
+    cog = factory.TilerFactory(add_preview=False, add_part=False)
+    assert len(cog.router.routes) == 17
+
+    app = FastAPI()
+    cog = factory.TilerFactory(optional_headers=[OptionalHeaders.server_timing])
+    app.include_router(cog.router)
+    client = TestClient(app)
 
-    app = factory.TilerFactory(reader=COGReader)
-    assert len(app.router.routes) == 21
-    assert app.tms_dependency == TMSParams
+    response = client.get(f"/tiles/8/87/48?url={DATA_DIR}/cog.tif&rescale=0,1000")
+    assert response.status_code == 200
+    assert response.headers["content-type"] == "image/jpeg"
+    timing = response.headers["server-timing"]
+    assert "dataread;dur" in timing
+    assert "postprocess;dur" in timing
+    assert "format;dur" in timing
 
-    app = factory.TilerFactory(reader=COGReader, add_preview=False, add_part=False)
-    assert len(app.router.routes) == 17
+    response = client.get(
+        f"/preview?url={DATA_DIR}/cog.tif&rescale=0,1000&max_size=256"
+    )
+    assert response.status_code == 200
+    assert response.headers["content-type"] == "image/jpeg"
+    timing = response.headers["server-timing"]
+    assert "dataread;dur" in timing
+    assert "postprocess;dur" in timing
+    assert "format;dur" in timing
 
+    response = client.get(
+        f"/crop/-56.228,72.715,-54.547,73.188.png?url={DATA_DIR}/cog.tif&rescale=0,1000&max_size=256"
+    )
+    assert response.status_code == 200
+    assert response.headers["content-type"] == "image/png"
+    timing = response.headers["server-timing"]
+    assert "dataread;dur" in timing
+    assert "postprocess;dur" in timing
+    assert "format;dur" in timing
 
-def test_MosaicTilerFactory(set_env):
+    response = client.get(f"/point/-56.228,72.715?url={DATA_DIR}/cog.tif")
+    assert response.status_code == 200
+    assert response.headers["content-type"] == "application/json"
+    timing = response.headers["server-timing"]
+    assert "dataread;dur" in timing
+
+
+@contextmanager
+def tmpmosaic():
+    """Create a Temporary MosaicJSON file."""
+    fileobj = tempfile.NamedTemporaryFile(suffix=".json.gz", delete=False)
+    fileobj.close()
+    mosaic_def = MosaicJSON.from_urls(assets)
+    with FileBackend(fileobj.name, mosaic_def=mosaic_def) as mosaic:
+        mosaic.write(overwrite=True)
+
+    try:
+        yield fileobj.name
+    finally:
+        os.remove(fileobj.name)
+
+
+def test_MosaicTilerFactory():
     """Test MosaicTilerFactory class."""
-    from titiler.dependencies import WebMercatorTMSParams
-    from titiler.endpoints import factory
+    mosaic = factory.MosaicTilerFactory(
+        optional_headers=[OptionalHeaders.server_timing, OptionalHeaders.x_assets],
+        router_prefix="mosaic",
+    )
+    assert len(mosaic.router.routes) == 19
+    assert mosaic.tms_dependency == WebMercatorTMSParams
+
+    app = FastAPI()
+    app.include_router(mosaic.router, prefix="/mosaic")
+    client = TestClient(app)
+
+    with tmpmosaic() as mosaic_file:
+        response = client.get(
+            "/mosaic/point/-74.53125,45.9956935", params={"url": mosaic_file},
+        )
+        assert response.status_code == 200
+        timing = response.headers["server-timing"]
+        assert "mosaicread;dur" in timing
+        assert "dataread;dur" in timing
+
+        response = client.get("/mosaic/tiles/7/37/45", params={"url": mosaic_file})
+        assert response.status_code == 200
 
-    app = factory.MosaicTilerFactory()
-    assert len(app.router.routes) == 19
-    assert app.tms_dependency == WebMercatorTMSParams
+        assert response.headers["X-Assets"]
+        timing = response.headers["server-timing"]
+        assert "mosaicread;dur" in timing
+        assert "dataread;dur" in timing
+        assert "postprocess;dur" in timing
+        assert "format;dur" in timing
diff --git a/tests/test_main.py b/tests/test_main.py
index 13c21d757..e6ceee2f2 100644
--- a/tests/test_main.py
+++ b/tests/test_main.py
@@ -6,4 +6,3 @@ def test_health(app):
     response = app.get("/healthz")
     assert response.status_code == 200
     assert response.json() == {"ping": "pong!"}
-    assert response.headers["server-timing"]
diff --git a/titiler/endpoints/factory.py b/titiler/endpoints/factory.py
index ae91118be..fc9259e9d 100644
--- a/titiler/endpoints/factory.py
+++ b/titiler/endpoints/factory.py
@@ -36,7 +36,12 @@
 )
 from ..models.mapbox import TileJSON
 from ..models.OGC import TileMatrixSetList
-from ..resources.enums import ImageType, MimeTypes, PixelSelectionMethod
+from ..resources.enums import (
+    ImageType,
+    MimeTypes,
+    OptionalHeaders,
+    PixelSelectionMethod,
+)
 from ..resources.responses import GeoJSONResponse, XMLResponse
 from ..templates import templates
 
@@ -100,6 +105,9 @@ class BaseTilerFactory(metaclass=abc.ABCMeta):
     # Add specific GDAL environement (e.g {"AWS_REQUEST_PAYER": "requester"})
     gdal_config: Dict = field(default_factory=dict)
 
+    # add additional headers in response
+    optional_headers: List[OptionalHeaders] = field(default_factory=list)
+
     def __post_init__(self):
         """Post Init: register route and configure specific options."""
         self.register_routes()
@@ -341,9 +349,10 @@ def tile(
                 )
             timings.append(("format", round(t.elapsed * 1000, 2)))
 
-            headers["Server-Timing"] = ", ".join(
-                [f"{name};dur={time}" for (name, time) in timings]
-            )
+            if OptionalHeaders.server_timing in self.optional_headers:
+                headers["Server-Timing"] = ", ".join(
+                    [f"{name};dur={time}" for (name, time) in timings]
+                )
 
             return Response(content, media_type=format.mimetype, headers=headers)
 
@@ -544,9 +553,10 @@ def point(
                         )
             timings.append(("dataread", round(t.elapsed * 1000, 2)))
 
-            response.headers["Server-Timing"] = ", ".join(
-                [f"{name};dur={time}" for (name, time) in timings]
-            )
+            if OptionalHeaders.server_timing in self.optional_headers:
+                response.headers["Server-Timing"] = ", ".join(
+                    [f"{name};dur={time}" for (name, time) in timings]
+                )
 
             return {"coordinates": [lon, lat], "values": values}
 
@@ -606,7 +616,7 @@ def preview(
                 )
             timings.append(("format", round(t.elapsed * 1000, 2)))
 
-            if timings:
+            if OptionalHeaders.server_timing in self.optional_headers:
                 headers["Server-Timing"] = ", ".join(
                     [f"{name};dur={time}" for (name, time) in timings]
                 )
@@ -674,7 +684,7 @@ def part(
                 )
             timings.append(("format", round(t.elapsed * 1000, 2)))
 
-            if timings:
+            if OptionalHeaders.server_timing in self.optional_headers:
                 headers["Server-Timing"] = ", ".join(
                     [f"{name};dur={time}" for (name, time) in timings]
                 )
@@ -934,6 +944,9 @@ class MosaicTilerFactory(BaseTilerFactory):
     # BaseBackend does not support other TMS than WebMercator
     tms_dependency: Callable[..., TileMatrixSet] = WebMercatorTMSParams
 
+    # Add X-Assets in response headers
+    add_assets_headers: bool = False
+
     def register_routes(self):
         """
         This Method register routes to the router.
@@ -1127,11 +1140,13 @@ def tile(
                 )
             timings.append(("format", round(t.elapsed * 1000, 2)))
 
-            headers["Server-Timing"] = ", ".join(
-                [f"{name};dur={time}" for (name, time) in timings]
-            )
+            if OptionalHeaders.server_timing in self.optional_headers:
+                headers["Server-Timing"] = ", ".join(
+                    [f"{name};dur={time}" for (name, time) in timings]
+                )
 
-            headers["X-Assets"] = ",".join(data.assets)
+            if OptionalHeaders.x_assets in self.optional_headers:
+                headers["X-Assets"] = ",".join(data.assets)
 
             return Response(content, media_type=format.mimetype, headers=headers)
 
@@ -1340,9 +1355,10 @@ def point(
                         )
             timings.append(("dataread", round((t.elapsed - mosaic_read) * 1000, 2)))
 
-            response.headers["Server-Timing"] = ", ".join(
-                [f"{name};dur={time}" for (name, time) in timings]
-            )
+            if OptionalHeaders.server_timing in self.optional_headers:
+                response.headers["Server-Timing"] = ", ".join(
+                    [f"{name};dur={time}" for (name, time) in timings]
+                )
 
             return {"coordinates": [lon, lat], "values": values}
 
diff --git a/titiler/main.py b/titiler/main.py
index 3aef83b9f..ea0d10a71 100644
--- a/titiler/main.py
+++ b/titiler/main.py
@@ -56,9 +56,9 @@
 
 app.add_middleware(BrotliMiddleware, minimum_size=0, gzip_fallback=True)
 app.add_middleware(CacheControlMiddleware, cachecontrol=api_settings.cachecontrol)
-app.add_middleware(TotalTimeMiddleware)
 if api_settings.debug:
-    app.add_middleware(LoggerMiddleware)
+    app.add_middleware(TotalTimeMiddleware)
+    app.add_middleware(LoggerMiddleware, headers=True, querystrings=True)
 
 
 @app.get("/healthz", description="Health Check", tags=["Health Check"])
diff --git a/titiler/resources/enums.py b/titiler/resources/enums.py
index 912265ccd..5f8fe3b96 100644
--- a/titiler/resources/enums.py
+++ b/titiler/resources/enums.py
@@ -77,3 +77,10 @@ class PixelSelectionMethod(str, Enum):
     def method(self):
         """Return rio-tiler-mosaic pixel selection class"""
         return getattr(defaults, f"{self._value_.title()}Method")
+
+
+class OptionalHeaders(str, Enum):
+    """Optional Headers in responses."""
+
+    server_timing = "Server-Timing"
+    x_assets = "X-Assets"