diff --git a/ragna/assistants/_ai21labs.py b/ragna/assistants/_ai21labs.py
index 19cfd59b..f941c999 100644
--- a/ragna/assistants/_ai21labs.py
+++ b/ragna/assistants/_ai21labs.py
@@ -2,10 +2,10 @@
 
 from ragna.core import Source
 
-from ._api import ApiAssistant
+from ._api import AuthenticatedApiAssistant
 
 
-class Ai21LabsAssistant(ApiAssistant):
+class Ai21LabsAssistant(AuthenticatedApiAssistant):
     _API_KEY_ENV_VAR = "AI21_API_KEY"
     _MODEL_TYPE: str
 
diff --git a/ragna/assistants/_anthropic.py b/ragna/assistants/_anthropic.py
index f5f4c538..4b44ce8e 100644
--- a/ragna/assistants/_anthropic.py
+++ b/ragna/assistants/_anthropic.py
@@ -3,10 +3,10 @@
 
 from ragna.core import PackageRequirement, RagnaException, Requirement, Source
 
-from ._api import ApiAssistant
+from ._api import AuthenticatedApiAssistant
 
 
-class AnthropicApiAssistant(ApiAssistant):
+class AnthropicApiAssistant(AuthenticatedApiAssistant):
     _API_KEY_ENV_VAR = "ANTHROPIC_API_KEY"
     _MODEL: str
 
diff --git a/ragna/assistants/_api.py b/ragna/assistants/_api.py
index 01041c2b..296476b8 100644
--- a/ragna/assistants/_api.py
+++ b/ragna/assistants/_api.py
@@ -11,12 +11,10 @@
 from ragna.core import Assistant, EnvVarRequirement, RagnaException, Requirement, Source
 
 
-class ApiAssistant(Assistant):
-    _API_KEY_ENV_VAR: str
-
+class _ApiAssistant(Assistant):
     @classmethod
     def requirements(cls) -> list[Requirement]:
-        return [EnvVarRequirement(cls._API_KEY_ENV_VAR), *cls._extra_requirements()]
+        return []
 
     @classmethod
     def _extra_requirements(cls) -> list[Requirement]:
@@ -27,7 +25,6 @@ def __init__(self) -> None:
             headers={"User-Agent": f"{ragna.__version__}/{self}"},
             timeout=60,
         )
-        self._api_key = os.environ[self._API_KEY_ENV_VAR]
 
     async def answer(
         self, prompt: str, sources: list[Source], *, max_new_tokens: int = 256
@@ -58,3 +55,20 @@ async def _assert_api_call_is_success(self, response: Response) -> None:
             response_status_code=response.status_code,
             response_content=content,
         )
+
+
+class AuthenticatedApiAssistant(_ApiAssistant):
+    _API_KEY_ENV_VAR: str
+
+    @classmethod
+    def requirements(cls) -> list[Requirement]:
+        return [EnvVarRequirement(cls._API_KEY_ENV_VAR), *cls._extra_requirements()]
+
+    def __init__(self) -> None:
+        super().__init__()
+        self._api_key = os.environ[self._API_KEY_ENV_VAR]
+
+
+class UnauthenticatedApiAssistant(_ApiAssistant):
+    def __init__(self) -> None:
+        super().__init__()
diff --git a/ragna/assistants/_cohere.py b/ragna/assistants/_cohere.py
index a93a264f..0525481b 100644
--- a/ragna/assistants/_cohere.py
+++ b/ragna/assistants/_cohere.py
@@ -3,10 +3,10 @@
 
 from ragna.core import RagnaException, Source
 
-from ._api import ApiAssistant
+from ._api import AuthenticatedApiAssistant
 
 
-class CohereApiAssistant(ApiAssistant):
+class CohereApiAssistant(AuthenticatedApiAssistant):
     _API_KEY_ENV_VAR = "COHERE_API_KEY"
     _MODEL: str
 
diff --git a/ragna/assistants/_google.py b/ragna/assistants/_google.py
index afbb829a..92998bb3 100644
--- a/ragna/assistants/_google.py
+++ b/ragna/assistants/_google.py
@@ -3,7 +3,7 @@
 from ragna._compat import anext
 from ragna.core import PackageRequirement, Requirement, Source
 
-from ._api import ApiAssistant
+from ._api import AuthenticatedApiAssistant
 
 
 # ijson does not support reading from an (async) iterator, but only from file-like
@@ -25,7 +25,7 @@ async def read(self, n: int) -> bytes:
         return await anext(self._ait, b"")  # type: ignore[call-arg]
 
 
-class GoogleApiAssistant(ApiAssistant):
+class GoogleApiAssistant(AuthenticatedApiAssistant):
     _API_KEY_ENV_VAR = "GOOGLE_API_KEY"
     _MODEL: str
 
diff --git a/ragna/assistants/_mosaicml.py b/ragna/assistants/_mosaicml.py
index 64edac1b..5e024d63 100644
--- a/ragna/assistants/_mosaicml.py
+++ b/ragna/assistants/_mosaicml.py
@@ -2,10 +2,10 @@
 
 from ragna.core import Source
 
-from ._api import ApiAssistant
+from ._api import AuthenticatedApiAssistant
 
 
-class MosaicmlApiAssistant(ApiAssistant):
+class MosaicmlApiAssistant(AuthenticatedApiAssistant):
     _API_KEY_ENV_VAR = "MOSAICML_API_KEY"
     _MODEL: str
 
diff --git a/ragna/assistants/_openai.py b/ragna/assistants/_openai.py
index a9dad3ee..4a1b0a46 100644
--- a/ragna/assistants/_openai.py
+++ b/ragna/assistants/_openai.py
@@ -3,10 +3,10 @@
 
 from ragna.core import PackageRequirement, Requirement, Source
 
-from ._api import ApiAssistant
+from ._api import AuthenticatedApiAssistant
 
 
-class OpenaiApiAssistant(ApiAssistant):
+class OpenaiApiAssistant(AuthenticatedApiAssistant):
     _API_KEY_ENV_VAR = "OPENAI_API_KEY"
     _MODEL: str
 
diff --git a/tests/assistants/test_api.py b/tests/assistants/test_api.py
index 97961456..5c84f3cf 100644
--- a/tests/assistants/test_api.py
+++ b/tests/assistants/test_api.py
@@ -4,7 +4,11 @@
 
 from ragna import assistants
 from ragna._compat import anext
-from ragna.assistants._api import ApiAssistant
+from ragna.assistants._api import (
+    AuthenticatedApiAssistant,
+    UnauthenticatedApiAssistant,
+    _ApiAssistant,
+)
 from ragna.core import RagnaException
 from tests.utils import skip_on_windows
 
@@ -12,8 +16,10 @@
     assistant
     for assistant in assistants.__dict__.values()
     if isinstance(assistant, type)
-    and issubclass(assistant, ApiAssistant)
-    and assistant is not ApiAssistant
+    and issubclass(assistant, _ApiAssistant)
+    and assistant is not _ApiAssistant
+    and assistant is not AuthenticatedApiAssistant
+    and assistant is not UnauthenticatedApiAssistant
 ]