diff --git a/aleph_alpha_client/aleph_alpha_client.py b/aleph_alpha_client/aleph_alpha_client.py
index 7e15e30..43afeb6 100644
--- a/aleph_alpha_client/aleph_alpha_client.py
+++ b/aleph_alpha_client/aleph_alpha_client.py
@@ -163,6 +163,7 @@ def __init__(
         total_retries: int = 8,
         nice: bool = False,
         verify_ssl=True,
+        tags: Optional[Sequence[str]] = None
     ) -> None:
         if host[-1] != "/":
             host += "/"
@@ -171,6 +172,7 @@ def __init__(
         self.request_timeout_seconds = request_timeout_seconds
         self.token = token
         self.nice = nice
+        self.tags = tags
 
         retry_strategy = Retry(
             total=total_retries,
@@ -242,6 +244,8 @@ def _build_json_body(
             json_body["model"] = model
         if self.hosting is not None:
             json_body["hosting"] = self.hosting
+        if self.tags is not None:
+            json_body["tags"] = self.tags
         return json_body
 
     def models(self) -> List[Mapping[str, Any]]:
@@ -647,6 +651,7 @@ def __init__(
         total_retries: int = 8,
         nice: bool = False,
         verify_ssl=True,
+        tags: Optional[Sequence[str]] = None
     ) -> None:
         if host[-1] != "/":
             host += "/"
@@ -655,6 +660,7 @@ def __init__(
         self.request_timeout_seconds = request_timeout_seconds
         self.token = token
         self.nice = nice
+        self.tags = tags
 
         retry_options = ExponentialRetry(
             attempts=total_retries + 1,
@@ -762,6 +768,8 @@ def _build_json_body(
             json_body["model"] = model
         if self.hosting is not None:
             json_body["hosting"] = self.hosting
+        if self.tags is not None:
+            json_body["tags"] = self.tags
         return json_body
 
     async def models(self) -> List[Mapping[str, Any]]:
diff --git a/tests/test_clients.py b/tests/test_clients.py
index d1b5f2e..1e920af 100644
--- a/tests/test_clients.py
+++ b/tests/test_clients.py
@@ -54,7 +54,7 @@ async def test_can_use_async_client_without_context_manager(model_name: str):
 
 
 def test_nice_flag_on_client(httpserver: HTTPServer):
-    httpserver.expect_request("/version").respond_with_data("OK")
+    httpserver.expect_request("/version").respond_with_data(MIN_API_VERSION)
 
     httpserver.expect_request(
         "/complete", query_string={"nice": "true"}
@@ -79,7 +79,7 @@ def test_nice_flag_on_client(httpserver: HTTPServer):
 
 
 async def test_nice_flag_on_async_client(httpserver: HTTPServer):
-    httpserver.expect_request("/version").respond_with_data("OK")
+    httpserver.expect_request("/version").respond_with_data(MIN_API_VERSION)
 
     httpserver.expect_request(
         "/complete",
@@ -96,10 +96,60 @@ async def test_nice_flag_on_async_client(httpserver: HTTPServer):
     request = CompletionRequest(prompt=Prompt.from_text("Hello world"))
 
     async with AsyncClient(
-        host=httpserver.url_for(""), token="AA_TOKEN", nice=True
+        host=httpserver.url_for(""), token="AA_TOKEN", nice=True, request_timeout_seconds=1
     ) as client:
         await client.complete(request, model="luminous")
 
+def test_tags_on_client(httpserver: HTTPServer):
+    httpserver.expect_request("/version").respond_with_data(MIN_API_VERSION)
+
+    request = CompletionRequest(prompt=Prompt.from_text("Hello world"))
+    body = request.to_json()
+    body["tags"] = ["tim-tagger"]
+    body["model"] = "luminous"
+    httpserver.expect_request(
+        "/complete", json=body
+    ).respond_with_json(
+        CompletionResponse(
+            "model_version",
+            [
+                CompletionResult(
+                    log_probs=[],
+                    completion="foo",
+                )
+            ],
+            num_tokens_prompt_total=2,
+            num_tokens_generated=1,
+        ).to_json()
+    )
+
+    client = Client(host=httpserver.url_for(""), request_timeout_seconds=1, token="AA_TOKEN", tags=["tim-tagger"])
+
+    client.complete(request, model="luminous")
+
+
+async def test_tags_on_async_client(httpserver: HTTPServer):
+    httpserver.expect_request("/version").respond_with_data(MIN_API_VERSION)
+
+    request = CompletionRequest(prompt=Prompt.from_text("Hello world"))
+    body = request.to_json()
+    body["tags"] = ["tim-tagger"]
+    body["model"] = "luminous"
+    httpserver.expect_request(
+        "/complete", json=body
+    ).respond_with_json(
+        CompletionResponse(
+            "model_version",
+            [CompletionResult(log_probs=[], completion="foo")],
+            num_tokens_prompt_total=2,
+            num_tokens_generated=1,
+        ).to_json()
+    )
+
+    async with AsyncClient(
+        host=httpserver.url_for(""), token="AA_TOKEN", tags=["tim-tagger"]
+    ) as client:
+        await client.complete(request, model="luminous")
 
 @pytest.mark.system_test
 def test_available_models_sync_client(sync_client: Client, model_name: str):