diff --git a/agent-team/agent_team/api.py b/agent-team/agent_team/api.py
index 8ba955c..730d0c8 100644
--- a/agent-team/agent_team/api.py
+++ b/agent-team/agent_team/api.py
@@ -63,6 +63,7 @@ _DEFAULT_PORT = 8765
 # Pydantic request/response models (module-level so FastAPI resolves them).
 # ---------------------------------------------------------------------------
 
+
 class TaskRequest(BaseModel):
     task: str
     transport: str = "claude_code"
@@ -89,6 +90,7 @@ class OrchestratorInvokeResponse(BaseModel):
 # Token helper.
 # ---------------------------------------------------------------------------
 
+
 def _get_token() -> str:
     """Read the API bearer token from the environment.
 
@@ -139,6 +141,7 @@ def _build_coordinator(db_path: str | Path | None = None) -> Any:
 # App factory.
 # ---------------------------------------------------------------------------
 
+
 def make_app(
     *,
     coordinator: Any = None,
@@ -179,7 +182,9 @@ def make_app(
     ) -> None:
         expected = _get_token()
         if creds is None or not hmac.compare_digest(creds.credentials, expected):
-            raise HTTPException(status_code=401, detail="invalid or missing bearer token")
+            raise HTTPException(
+                status_code=401, detail="invalid or missing bearer token"
+            )
 
     # Coordinator is built lazily and cached on first use so test clients that
     # inject a pre-built coordinator never trigger the DB path.
@@ -194,7 +199,9 @@ def make_app(
             _state["ready"] = True
         return coord
 
-    @app.post("/tasks", response_model=TaskResponse, dependencies=[Depends(_check_token)])
+    @app.post(
+        "/tasks", response_model=TaskResponse, dependencies=[Depends(_check_token)]
+    )
     def create_task(request: TaskRequest) -> TaskResponse:
         """Intake a new agent-team task and run it to the first human gate."""
         coord = _get_coordinator()
@@ -233,7 +240,9 @@ def make_app(
         response_model=OrchestratorInvokeResponse,
         dependencies=[Depends(_check_token)],
     )
-    def orchestrator_invoke(request: OrchestratorInvokeRequest) -> OrchestratorInvokeResponse:
+    def orchestrator_invoke(
+        request: OrchestratorInvokeRequest,
+    ) -> OrchestratorInvokeResponse:
         """Route a one-shot prompt through the root orchestrator run.py.
 
         Shells out to the orchestrator root's ``run.py`` with the prompt text.
@@ -272,6 +281,7 @@ def make_app(
 # Attended deploy helper (do NOT call in tests or CI).
 # ---------------------------------------------------------------------------
 
+
 def serve(
     *,
     host: str = _DEFAULT_HOST,
diff --git a/agent-team/agent_team/invoker_multi.py b/agent-team/agent_team/invoker_multi.py
index a34ffd8..384c085 100644
--- a/agent-team/agent_team/invoker_multi.py
+++ b/agent-team/agent_team/invoker_multi.py
@@ -96,8 +96,7 @@ def _load_model(key: str) -> Any:
     }
     if key not in factories:
         raise ValueError(
-            f"unknown model key {key!r}; must be one of: "
-            + ", ".join(sorted(MODELS))
+            f"unknown model key {key!r}; must be one of: " + ", ".join(sorted(MODELS))
         )
     return factories[key]()
 
diff --git a/agent-team/agent_team/nodes/builders_llm.py b/agent-team/agent_team/nodes/builders_llm.py
index 5440e11..7f3ad78 100644
--- a/agent-team/agent_team/nodes/builders_llm.py
+++ b/agent-team/agent_team/nodes/builders_llm.py
@@ -177,7 +177,9 @@ def make_fast_coder_invoker() -> "BuildCallable":
     return _invoke
 
 
-def subprocess_build(instruction: str, *, route: _OrchestratorRoute | None = None) -> str:
+def subprocess_build(
+    instruction: str, *, route: _OrchestratorRoute | None = None
+) -> str:
     """Opt-in fallback :data:`BuildCallable`: shell out to ``run.py fast_coder``.
 
     The original subprocess-based build path, retained as an opt-in alternative
diff --git a/agent-team/tests/test_builders_llm.py b/agent-team/tests/test_builders_llm.py
index cacfc46..535fd5d 100644
--- a/agent-team/tests/test_builders_llm.py
+++ b/agent-team/tests/test_builders_llm.py
@@ -337,6 +337,7 @@ def test_default_build_is_the_injection_default() -> None:
     src = inspect.getsource(default_build)
     assert "make_fast_coder_invoker" in src
     from agent_team.nodes.builders_llm import subprocess_build
+
     subprocess_src = inspect.getsource(subprocess_build)
     assert "subprocess.run" in subprocess_src
 
diff --git a/agent-team/tests/test_ws1_invoker_multi_api.py b/agent-team/tests/test_ws1_invoker_multi_api.py
index f6c7786..775c869 100644
--- a/agent-team/tests/test_ws1_invoker_multi_api.py
+++ b/agent-team/tests/test_ws1_invoker_multi_api.py
@@ -12,6 +12,7 @@ Covers:
 
 from __future__ import annotations
 
+import importlib.util
 import sys
 from pathlib import Path
 from typing import Any
@@ -180,7 +181,9 @@ def test_review_loop_llm_default_is_cross_reviewer_invoker() -> None:
     saved = sys.modules.pop("models", None)
     try:
         with patch.dict(sys.modules, {"models": None}):  # type: ignore[dict-item]
-            with pytest.raises((RuntimeError, AttributeError, TypeError, ModuleNotFoundError)):
+            with pytest.raises(
+                (RuntimeError, AttributeError, TypeError, ModuleNotFoundError)
+            ):
                 fn("any prompt")
     finally:
         if saved is not None:
@@ -232,6 +235,15 @@ def test_builders_llm_default_build_uses_in_process() -> None:
 # api.py: bearer-token auth + endpoint smoke tests via FastAPI TestClient
 # ---------------------------------------------------------------------------
 
+# fastapi is a box-only dependency (installed on the R720 during attended
+# deploy, never in CI or the root requirements). api.py imports it lazily, so
+# these TestClient-based smoke tests are the only thing that hard-requires it.
+# Skip them when it is absent rather than failing collection in CI.
+requires_fastapi = pytest.mark.skipif(
+    importlib.util.find_spec("fastapi") is None,
+    reason="fastapi not installed (box-only dependency)",
+)
+
 
 @pytest.fixture()
 def api_token(monkeypatch: Any) -> str:
@@ -249,6 +261,7 @@ def _make_stub_coordinator(thread_id: str = "t-test-123") -> MagicMock:
     return coord
 
 
+@requires_fastapi
 def test_api_401_without_token(api_token: str) -> None:
     from fastapi.testclient import TestClient
 
@@ -260,6 +273,7 @@ def test_api_401_without_token(api_token: str) -> None:
     assert resp.status_code == 401
 
 
+@requires_fastapi
 def test_api_401_wrong_token(api_token: str) -> None:
     from fastapi.testclient import TestClient
 
@@ -275,6 +289,7 @@ def test_api_401_wrong_token(api_token: str) -> None:
     assert resp.status_code == 401
 
 
+@requires_fastapi
 def test_api_post_tasks_200(api_token: str) -> None:
     from fastapi.testclient import TestClient
 
@@ -293,6 +308,7 @@ def test_api_post_tasks_200(api_token: str) -> None:
     stub.start_task.assert_called_once()
 
 
+@requires_fastapi
 def test_api_get_task_404_no_state(api_token: str) -> None:
     from fastapi.testclient import TestClient
 
@@ -309,6 +325,7 @@ def test_api_get_task_404_no_state(api_token: str) -> None:
     assert resp.status_code == 503
 
 
+@requires_fastapi
 def test_api_get_task_with_graph_state(api_token: str) -> None:
     from fastapi.testclient import TestClient
 
@@ -332,7 +349,10 @@ def test_api_get_task_with_graph_state(api_token: str) -> None:
     assert data["state"]["task"] == "add login"
 
 
-def test_api_orchestrator_invoke_calls_subprocess(api_token: str, tmp_path: Any) -> None:
+@requires_fastapi
+def test_api_orchestrator_invoke_calls_subprocess(
+    api_token: str, tmp_path: Any
+) -> None:
     from fastapi.testclient import TestClient
 
     from agent_team.api import make_app
@@ -357,6 +377,7 @@ def test_api_orchestrator_invoke_calls_subprocess(api_token: str, tmp_path: Any)
     assert "hello world" in resp.json()["text"]
 
 
+@requires_fastapi
 def test_api_no_token_env_raises_on_request(monkeypatch: Any) -> None:
     from fastapi.testclient import TestClient