diff --git a/clients/python/client/osparc/__init__.py b/clients/python/client/osparc/__init__.py
index 8567dd59..af097ee9 100644
--- a/clients/python/client/osparc/__init__.py
+++ b/clients/python/client/osparc/__init__.py
@@ -4,7 +4,6 @@
 
 import nest_asyncio
 from osparc_client import (  # APIs; API client; models
-    ApiClient,
     ApiException,
     ApiKeyError,
     ApiTypeError,
@@ -38,6 +37,7 @@
 )
 from packaging.version import Version
 
+from ._api_client import ApiClient
 from ._exceptions import RequestError, VisibleDeprecationWarning
 from ._files_api import FilesApi
 from ._info import openapi
@@ -114,4 +114,4 @@
     "UsersApi",
     "UsersGroup",
     "ValidationError",
-)
+)  # type: ignore
diff --git a/clients/python/client/osparc/_api_client.py b/clients/python/client/osparc/_api_client.py
new file mode 100644
index 00000000..a30c51d5
--- /dev/null
+++ b/clients/python/client/osparc/_api_client.py
@@ -0,0 +1,37 @@
+from typing import Optional
+
+from osparc_client import ApiClient as _ApiClient
+from osparc_client import Configuration
+from pydantic import ValidationError
+
+from ._models import ConfigurationModel
+
+
+class ApiClient(_ApiClient):
+    def __init__(
+        self,
+        configuration: Optional[Configuration] = None,
+        header_name=None,
+        header_value=None,
+        cookie=None,
+        pool_threads=1,
+    ):
+        if configuration is None:
+            try:
+                env_vars = ConfigurationModel()
+                configuration = Configuration(
+                    host=f"{env_vars.OSPARC_API_HOST}".rstrip(
+                        "/"
+                    ),  # https://github.com/pydantic/pydantic/issues/7186
+                    username=env_vars.OSPARC_API_KEY,
+                    password=env_vars.OSPARC_API_SECRET,
+                )
+            except ValidationError as exc:
+                raise RuntimeError(
+                    "Could not initialize configuration from environment. "
+                    "If your osparc host, key and secret are not exposed as "
+                    "environment variables you must construct the "
+                    "Configuration object explicitly"
+                ) from exc
+
+        super().__init__(configuration, header_name, header_value, cookie, pool_threads)
diff --git a/clients/python/client/osparc/_files_api.py b/clients/python/client/osparc/_files_api.py
index 401e43b5..a9b8bd42 100644
--- a/clients/python/client/osparc/_files_api.py
+++ b/clients/python/client/osparc/_files_api.py
@@ -21,7 +21,8 @@
 from tqdm.asyncio import tqdm
 from tqdm.contrib.logging import logging_redirect_tqdm
 
-from . import ApiClient, File
+from . import File
+from ._api_client import ApiClient
 from ._http_client import AsyncHttpClient
 from ._utils import (
     DEFAULT_TIMEOUT_SECONDS,
@@ -36,7 +37,7 @@
 class FilesApi(_FilesApi):
     """Class for interacting with files"""
 
-    def __init__(self, api_client: Optional[ApiClient] = None):
+    def __init__(self, api_client: ApiClient):
         """Construct object
 
         Args:
diff --git a/clients/python/client/osparc/_models.py b/clients/python/client/osparc/_models.py
index 4e5ea3cc..b5266f28 100644
--- a/clients/python/client/osparc/_models.py
+++ b/clients/python/client/osparc/_models.py
@@ -1,7 +1,7 @@
 from typing import Optional
 from uuid import UUID
 
-from pydantic import Field, field_validator
+from pydantic import AnyHttpUrl, Field, field_validator
 from pydantic_settings import BaseSettings
 
 
@@ -18,7 +18,19 @@ class ParentProjectInfo(BaseSettings):
 
     @field_validator("x_simcore_parent_project_uuid", "x_simcore_parent_node_id")
     @classmethod
-    def _validate_uuids(cls, v: Optional[str]) -> str:
+    def _validate_uuids(cls, v: Optional[str]) -> Optional[str]:
         if v is not None:
             _ = UUID(v)
         return v
+
+
+class ConfigurationModel(BaseSettings):
+    """Model for capturing env vars which should go into the Configuration"""
+
+    OSPARC_API_HOST: AnyHttpUrl = Field(
+        default=...,
+        description="OSPARC api url",
+        examples=["https://api.osparc-master.speag.com/"],
+    )
+    OSPARC_API_KEY: str = Field(default=..., description="OSPARC api key")
+    OSPARC_API_SECRET: str = Field(default=..., description="OSPARC api secret")
diff --git a/clients/python/client/osparc/_solvers_api.py b/clients/python/client/osparc/_solvers_api.py
index 714337a2..6a3d6aa2 100644
--- a/clients/python/client/osparc/_solvers_api.py
+++ b/clients/python/client/osparc/_solvers_api.py
@@ -4,7 +4,7 @@
 from osparc_client import JobInputs, OnePageSolverPort, SolverPort
 from osparc_client import SolversApi as _SolversApi
 
-from . import ApiClient
+from ._api_client import ApiClient
 from ._models import ParentProjectInfo
 from ._utils import (
     _DEFAULT_PAGINATION_LIMIT,
@@ -27,7 +27,7 @@ def __getattr__(self, name: str) -> Any:
             raise NotImplementedError(f"SolversApi.{name} is still under development")
         return super().__getattribute__(name)
 
-    def __init__(self, api_client: Optional[ApiClient] = None):
+    def __init__(self, api_client: ApiClient):
         """Construct object
 
         Args:
diff --git a/clients/python/client/osparc/_studies_api.py b/clients/python/client/osparc/_studies_api.py
index 3bc07578..887b99df 100644
--- a/clients/python/client/osparc/_studies_api.py
+++ b/clients/python/client/osparc/_studies_api.py
@@ -5,10 +5,11 @@
 from typing import Any, Optional
 
 import httpx
-from osparc_client import ApiClient, JobInputs, JobLogsMap, PageStudy
+from osparc_client import JobInputs, JobLogsMap, PageStudy
 from osparc_client import StudiesApi as _StudiesApi
 from tqdm.asyncio import tqdm_asyncio
 
+from ._api_client import ApiClient
 from ._http_client import AsyncHttpClient
 from ._models import ParentProjectInfo
 from ._utils import (
@@ -39,7 +40,7 @@ class StudiesApi(_StudiesApi):
         "stop_study_job",
     ]
 
-    def __init__(self, api_client: Optional[ApiClient] = None):
+    def __init__(self, api_client: ApiClient):
         """Construct object
 
         Args:
diff --git a/clients/python/test/e2e/conftest.py b/clients/python/test/e2e/conftest.py
index f7822d93..20c94b03 100644
--- a/clients/python/test/e2e/conftest.py
+++ b/clients/python/test/e2e/conftest.py
@@ -4,6 +4,7 @@
 # pylint: disable=unused-argument
 # pylint: disable=unused-variable
 
+import datetime
 import logging
 import os
 from pathlib import Path
@@ -14,6 +15,7 @@
 import pytest
 from httpx import AsyncClient, BasicAuth
 from numpy import random
+from osparc._models import ConfigurationModel
 from pydantic import ByteSize
 
 _KB: ByteSize = ByteSize(1024)  # in bytes
@@ -21,30 +23,85 @@
 _GB: ByteSize = ByteSize(_MB * 1024)  # in bytes
 
 
-@pytest.fixture
-def configuration() -> osparc.Configuration:
-    assert (host := os.environ.get("OSPARC_API_HOST"))
-    assert (username := os.environ.get("OSPARC_API_KEY"))
-    assert (password := os.environ.get("OSPARC_API_SECRET"))
-    return osparc.Configuration(
-        host=host,
-        username=username,
-        password=password,
-    )
+# Dictionary to store start times of tests
+_test_start_times = {}
+
+
+def _utc_now():
+    return datetime.datetime.now(tz=datetime.timezone.utc)
+
+
+def _construct_graylog_url(api_host, start_time, end_time):
+    """
+    Construct a Graylog URL for the given time interval.
+    """
+    base_url = api_host.replace("api.", "monitoring.", 1).rstrip("/")
+    url = f"{base_url}/graylog/search"
+    start_time_str = start_time.strftime("%Y-%m-%dT%H:%M:%S.%fZ")
+    end_time_str = end_time.strftime("%Y-%m-%dT%H:%M:%S.%fZ")
+    query = f"from={start_time_str}&to={end_time_str}"
+    return f"{url}?{query}"
+
+
+def pytest_runtest_setup(item):
+    """
+    Hook to capture the start time of each test.
+    """
+    _test_start_times[item.name] = _utc_now()
+
+
+def pytest_runtest_makereport(item, call):
+    """
+    Hook to add extra information when a test fails.
+    """
+    if call.when == "call":
+        # Check if the test failed
+        if call.excinfo is not None:
+            test_name = item.name
+            test_location = item.location
+            api_host = os.environ.get("OSPARC_API_HOST", "")
+
+            diagnostics = {
+                "test_name": test_name,
+                "test_location": test_location,
+                "api_host": api_host,
+            }
+
+            # Get the start and end times of the test
+            start_time = _test_start_times.get(test_name)
+            end_time = _utc_now()
+
+            if start_time:
+                diagnostics["graylog_url"] = _construct_graylog_url(
+                    api_host, start_time, end_time
+                )
+
+            # Print the diagnostics
+            print(f"\nDiagnostics for {test_name}:")
+            for key, value in diagnostics.items():
+                print("  ", key, ":", value)
+
+
+@pytest.hookimpl(tryfirst=True)
+def pytest_configure(config):
+    config.pluginmanager.register(pytest_runtest_setup, "osparc_test_times_plugin")
+    config.pluginmanager.register(pytest_runtest_makereport, "osparc_makereport_plugin")
 
 
 @pytest.fixture
-def api_client(configuration: osparc.Configuration) -> Iterable[osparc.ApiClient]:
-    with osparc.ApiClient(configuration=configuration) as _api_client:
-        yield _api_client
+def api_client() -> Iterable[osparc.ApiClient]:
+    with osparc.ApiClient() as api_client:
+        yield api_client
 
 
 @pytest.fixture
-def async_client(configuration: osparc.Configuration) -> AsyncClient:
-    return AsyncClient(
-        base_url=configuration.host,
+def async_client() -> Iterable[AsyncClient]:
+    configuration = ConfigurationModel()
+    yield AsyncClient(
+        base_url=f"{configuration.OSPARC_API_HOST}".rstrip("/"),
         auth=BasicAuth(
-            username=configuration.username, password=configuration.password
+            username=configuration.OSPARC_API_KEY,
+            password=configuration.OSPARC_API_SECRET,
         ),
     )  # type: ignore
 
diff --git a/clients/python/test/test_osparc/conftest.py b/clients/python/test/test_osparc/conftest.py
index a0947987..67dfd069 100644
--- a/clients/python/test/test_osparc/conftest.py
+++ b/clients/python/test/test_osparc/conftest.py
@@ -2,6 +2,7 @@
 import pytest
 from faker import Faker
 
+
 @pytest.fixture
 def cfg(faker: Faker) -> osparc.Configuration:
     return osparc.Configuration(
@@ -12,5 +13,10 @@ def cfg(faker: Faker) -> osparc.Configuration:
 
 
 @pytest.fixture
-def dev_mode_enabled(monkeypatch:pytest.MonkeyPatch):
+def api_client(cfg: osparc.Configuration) -> osparc.ApiClient:
+    return osparc.ApiClient(configuration=cfg)
+
+
+@pytest.fixture
+def dev_mode_enabled(monkeypatch: pytest.MonkeyPatch) -> None:
     monkeypatch.setenv("OSPARC_DEV_FEATURES_ENABLED", "1")
diff --git a/clients/python/test/test_osparc/test_apis.py b/clients/python/test/test_osparc/test_apis.py
index 1a094572..4f01a961 100644
--- a/clients/python/test/test_osparc/test_apis.py
+++ b/clients/python/test/test_osparc/test_apis.py
@@ -4,11 +4,11 @@
 # pylint: disable=too-many-arguments
 
 import os
-from typing import Callable
+from typing import Callable, Optional
 
 import pytest
 from faker import Faker
-from osparc import SolversApi, StudiesApi
+from osparc import ApiClient, SolversApi, StudiesApi
 from pytest_mock import MockerFixture
 
 
@@ -31,6 +31,7 @@ def test_create_jobs_parent_headers(
     create_parent_env: Callable,
     dev_mode_enabled: None,
     parent_env: bool,
+    api_client: ApiClient,
 ):
     create_parent_env(parent_env)
 
@@ -58,9 +59,43 @@ def check_headers(**kwargs):
         side_effect=lambda study_id, **kwargs: check_headers(**kwargs),
     )
 
-    solvers_api = SolversApi()
+    solvers_api = SolversApi(api_client=api_client)
     solvers_api.create_job(solver_key="mysolver", version="1.2.3", job_inputs={})
 
-    studies_api = StudiesApi()
+    studies_api = StudiesApi(api_client=api_client)
     studies_api.create_study_job(study_id=faker.uuid4(), job_inputs={})
     studies_api.clone_study(study_id=faker.uuid4())
+
+
+@pytest.mark.parametrize(
+    "OSPARC_API_HOST", ["https://api.foo.com", "https://api.bar.com/", None]
+)
+@pytest.mark.parametrize("OSPARC_API_KEY", ["key", None])
+@pytest.mark.parametrize("OSPARC_API_SECRET", ["secret", None])
+def test_api_client_constructor(
+    monkeypatch: pytest.MonkeyPatch,
+    OSPARC_API_HOST: Optional[str],
+    OSPARC_API_KEY: Optional[str],
+    OSPARC_API_SECRET: Optional[str],
+):
+    with monkeypatch.context() as patch:
+        patch.delenv("OSPARC_API_HOST", raising=False)
+        patch.delenv("OSPARC_API_KEY", raising=False)
+        patch.delenv("OSPARC_API_SECRET", raising=False)
+
+        if OSPARC_API_HOST is not None:
+            patch.setenv("OSPARC_API_HOST", OSPARC_API_HOST)
+        if OSPARC_API_KEY is not None:
+            patch.setenv("OSPARC_API_KEY", OSPARC_API_KEY)
+        if OSPARC_API_SECRET is not None:
+            patch.setenv("OSPARC_API_SECRET", OSPARC_API_SECRET)
+
+        if OSPARC_API_HOST and OSPARC_API_KEY and OSPARC_API_SECRET:
+            api = ApiClient()
+            assert api.configuration.host == OSPARC_API_HOST.rstrip("/")
+            assert api.configuration.username == OSPARC_API_KEY
+            assert api.configuration.password == OSPARC_API_SECRET
+
+        else:
+            with pytest.raises(RuntimeError):
+                ApiClient()
diff --git a/clients/python/test/test_osparc/test_osparc_client/test_files_api.py b/clients/python/test/test_osparc/test_osparc_client/test_files_api.py
index 62bfa9a4..d08ccad7 100644
--- a/clients/python/test/test_osparc/test_osparc_client/test_files_api.py
+++ b/clients/python/test/test_osparc/test_osparc_client/test_files_api.py
@@ -14,14 +14,16 @@
 
 import unittest
 
-from osparc import FilesApi  # noqa: E501
+from osparc import ApiClient, Configuration, FilesApi  # noqa: E501
 
 
 class TestFilesApi(unittest.TestCase):
     """FilesApi unit test stubs"""
 
     def setUp(self):
-        self.api = FilesApi()  # noqa: E501
+        self.api = FilesApi(
+            api_client=ApiClient(configuration=Configuration())
+        )  # noqa: E501
 
     def tearDown(self):
         pass
diff --git a/clients/python/test/test_osparc/test_osparc_client/test_meta_api.py b/clients/python/test/test_osparc/test_osparc_client/test_meta_api.py
index 44dbdd23..3499ff77 100644
--- a/clients/python/test/test_osparc/test_osparc_client/test_meta_api.py
+++ b/clients/python/test/test_osparc/test_osparc_client/test_meta_api.py
@@ -14,14 +14,16 @@
 
 import unittest
 
-from osparc import MetaApi  # noqa: E501
+from osparc import ApiClient, Configuration, MetaApi  # noqa: E501
 
 
 class TestMetaApi(unittest.TestCase):
     """MetaApi unit test stubs"""
 
     def setUp(self):
-        self.api = MetaApi()  # noqa: E501
+        self.api = MetaApi(
+            api_client=ApiClient(configuration=Configuration())
+        )  # noqa: E501
 
     def tearDown(self):
         pass
diff --git a/clients/python/test/test_osparc/test_osparc_client/test_solvers_api.py b/clients/python/test/test_osparc/test_osparc_client/test_solvers_api.py
index 55709aaa..71078984 100644
--- a/clients/python/test/test_osparc/test_osparc_client/test_solvers_api.py
+++ b/clients/python/test/test_osparc/test_osparc_client/test_solvers_api.py
@@ -14,14 +14,16 @@
 
 import unittest
 
-from osparc import SolversApi  # noqa: E501
+from osparc import ApiClient, Configuration, SolversApi  # noqa: E501
 
 
 class TestSolversApi(unittest.TestCase):
     """SolversApi unit test stubs"""
 
     def setUp(self):
-        self.api = SolversApi()  # noqa: E501
+        self.api = SolversApi(
+            api_client=ApiClient(configuration=Configuration())
+        )  # noqa: E501
 
     def tearDown(self):
         pass
diff --git a/clients/python/test/test_osparc/test_osparc_client/test_users_api.py b/clients/python/test/test_osparc/test_osparc_client/test_users_api.py
index f4a3cf7a..ae4073c6 100644
--- a/clients/python/test/test_osparc/test_osparc_client/test_users_api.py
+++ b/clients/python/test/test_osparc/test_osparc_client/test_users_api.py
@@ -14,14 +14,16 @@
 
 import unittest
 
-from osparc import UsersApi  # noqa: E501
+from osparc import ApiClient, Configuration, UsersApi  # noqa: E501
 
 
 class TestUsersApi(unittest.TestCase):
     """UsersApi unit test stubs"""
 
     def setUp(self):
-        self.api = UsersApi()  # noqa: E501
+        self.api = UsersApi(
+            api_client=ApiClient(configuration=Configuration())
+        )  # noqa: E501
 
     def tearDown(self):
         pass