diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index cbb32aa3e9..e98ac6b473 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -88,6 +88,7 @@ jobs:
         cd src/cli
         pip install -r requirements-lint.txt
         flake8 .
+        black ./__app__/ ./tests --check
         isort --profile black ./onefuzz ./examples/ ./tests/ --check
         mypy . --ignore-missing-imports
         pytest -v tests
@@ -166,6 +167,7 @@ jobs:
         pip install -r requirements-dev.txt
         pytest
         flake8 .
+        black ./__app__/ ./tests --check
         isort --profile black ./__app__/ ./tests --check
         mypy __app__
 
diff --git a/src/api-service/__app__/agent_can_schedule/__init__.py b/src/api-service/__app__/agent_can_schedule/__init__.py
index 3f730bd698..e20fc3c674 100644
--- a/src/api-service/__app__/agent_can_schedule/__init__.py
+++ b/src/api-service/__app__/agent_can_schedule/__init__.py
@@ -39,7 +39,8 @@ def post(req: func.HttpRequest) -> func.HttpResponse:
         )
         allowed = False
         stop_message = NodeMessage(
-            agent_id=node.machine_id, message=NodeCommand(stop=StopNodeCommand()),
+            agent_id=node.machine_id,
+            message=NodeCommand(stop=StopNodeCommand()),
         )
         stop_message.save()
 
diff --git a/src/api-service/requirements-dev.txt b/src/api-service/requirements-dev.txt
index 73795ff63e..00794cd8bb 100644
--- a/src/api-service/requirements-dev.txt
+++ b/src/api-service/requirements-dev.txt
@@ -3,4 +3,5 @@ pytest
 flake8
 mypy
 isort
-vulture
\ No newline at end of file
+vulture
+black
diff --git a/src/ci/onefuzztypes.sh b/src/ci/onefuzztypes.sh
index 6e13136eb5..06009cc4ab 100755
--- a/src/ci/onefuzztypes.sh
+++ b/src/ci/onefuzztypes.sh
@@ -12,6 +12,7 @@ pip install -r requirements-dev.txt
 python setup.py sdist bdist_wheel
 
 pip install -r requirements-lint.txt
+black ./onefuzztypes --check
 flake8 ./onefuzztypes
 isort --profile black ./onefuzztypes --check
 mypy ./onefuzztypes --ignore-missing-imports
diff --git a/src/cli/onefuzz/status/cache.py b/src/cli/onefuzz/status/cache.py
index 5e694c2ffc..e4baaf70d1 100644
--- a/src/cli/onefuzz/status/cache.py
+++ b/src/cli/onefuzz/status/cache.py
@@ -197,7 +197,7 @@ def render_pools(self) -> List:
                 pool.name,
                 pool.os,
                 pool.state,
-                nodes,
+                nodes or "None",
             ]
             results.append(entry)
         return results
diff --git a/src/cli/requirements-lint.txt b/src/cli/requirements-lint.txt
index 08109915e1..27a97b8b59 100644
--- a/src/cli/requirements-lint.txt
+++ b/src/cli/requirements-lint.txt
@@ -2,4 +2,5 @@ flake8
 mypy
 pytest
 isort
-vulture
\ No newline at end of file
+vulture
+black
diff --git a/src/pytypes/onefuzztypes/models.py b/src/pytypes/onefuzztypes/models.py
index 87d705f4b8..87355f468b 100644
--- a/src/pytypes/onefuzztypes/models.py
+++ b/src/pytypes/onefuzztypes/models.py
@@ -42,10 +42,10 @@ def exactly_one(cls: Any, values: Any) -> Any:
                 some.append(field)
 
         if not some:
-            raise ValueError('no variant set for enum')
+            raise ValueError("no variant set for enum")
 
         if len(some) > 1:
-            raise ValueError('multiple values set for enum: %s' % some)
+            raise ValueError("multiple values set for enum: %s" % some)
 
         return values
 
diff --git a/src/pytypes/requirements-lint.txt b/src/pytypes/requirements-lint.txt
index 11404bee76..4568b5e405 100644
--- a/src/pytypes/requirements-lint.txt
+++ b/src/pytypes/requirements-lint.txt
@@ -4,3 +4,4 @@ pytest
 isort
 pydantic
 vulture
+black