diff --git a/core/interactive_question.py b/core/interactive_question.py
index 09535f3..9abe6d4 100644
--- a/core/interactive_question.py
+++ b/core/interactive_question.py
@@ -110,24 +110,33 @@ class QuestionManager:
             raise TimeoutError(f"Question {question.question_id} timed out waiting for human input")
         finally:
             self._futures.pop(question.question_id, None)
+            self._pending.pop(question.question_id, None)
 
     def answer_question(self, question_id: str, answer: Any) -> bool:
-        """Called when human operator submits an answer from the UI."""
+        """Called when human operator submits an answer from the UI.
+
+        Returns False if the question is unknown or was already answered."""
         question = self._pending.get(question_id)
         if not question:
             logger.warning(f"No pending question found for id {question_id}")
             return False
+        if question.answered:
+            logger.warning(f"Question {question_id} already answered; ignoring")
+            return False
 
         question.answered = True
         question.answer = answer
 
         fut = self._futures.get(question_id)
         if fut and not fut.done():
-            fut.set_result(answer)
-            return True
-
+            fut.set_result(answer)  # wait_for_answer() removes it from _pending
+        else:
+            self._pending.pop(question_id, None)  # nobody waiting; don't leak
         return True
 
+    def list_pending(self) -> List[Question]:
+        return [q for q in self._pending.values() if not q.answered]
+
     def get_pending(self, question_id: str) -> Optional[Question]:
         return self._pending.get(question_id)
 
diff --git a/core/logger.py b/core/logger.py
index ca44df3..806a74a 100644
--- a/core/logger.py
+++ b/core/logger.py
@@ -1,33 +1,27 @@
-"""Structured logging for LogiFlow AI — loguru setup with standard logging fallback."""
+"""Structured logging for LogiFlow AI — single loguru setup imported by all modules."""
 import sys
 import os
-import logging
 from pathlib import Path
+from loguru import logger
 
-try:
-    from loguru import logger
+Path("logs").mkdir(exist_ok=True)
 
-    Path("logs").mkdir(exist_ok=True)
+logger.remove()
 
-    logger.remove()
+logger.add(
+    sys.stderr,
+    format="{time:YYYY-MM-DD HH:mm:ss} | {level: <8} | {name}:{function}:{line} - {message}",
+    level=os.getenv("LOG_LEVEL", "INFO"),
+    colorize=False,
+)
 
-    logger.add(
-        sys.stderr,
-        format="{time:YYYY-MM-DD HH:mm:ss} | {level: <8} | {name}:{function}:{line} - {message}",
-        level=os.getenv("LOG_LEVEL", "INFO"),
-        colorize=False,
-    )
-
-    logger.add(
-        "logs/logiflow_{time:YYYY-MM-DD}.log",
-        rotation="100 MB",
-        retention="30 days",
-        compression="gz",
-        level="DEBUG",
-        format="{time:YYYY-MM-DD HH:mm:ss} | {level: <8} | {name}:{function}:{line} - {message}",
-    )
-except ImportError:
-    logging.basicConfig(level=logging.INFO, format="%(asctime)s | %(levelname)-8s | %(message)s")
-    logger = logging.getLogger("logiflow")
+logger.add(
+    "logs/logiflow_{time:YYYY-MM-DD}.log",
+    rotation="100 MB",
+    retention="30 days",
+    compression="gz",
+    level="DEBUG",
+    format="{time:YYYY-MM-DD HH:mm:ss} | {level: <8} | {name}:{function}:{line} - {message}",
+)
 
 __all__ = ["logger"]
diff --git a/core/message_bus.py b/core/message_bus.py
index e33e26d..a79ac9a 100644
--- a/core/message_bus.py
+++ b/core/message_bus.py
@@ -8,11 +8,8 @@ from collections import defaultdict
 from dataclasses import dataclass
 from enum import Enum
 
-try:
-    import nats
-    import nats.js.errors
-except ImportError:
-    nats = None
+import nats
+import nats.js.errors
 
 from core.types import AgentMessage, MessageType
 from core.logger import logger
@@ -59,9 +56,6 @@ class MessageBus:
 
     async def connect(self):
         """Connect to NATS and create the logistics JetStream stream."""
-        if nats is None:
-            logger.warning("nats-py not installed; message bus running in local in-memory mode")
-            return
         self._nc = await nats.connect(
             servers=[f"nats://{NATS_HOST}:{NATS_PORT}"],
             user=NATS_USER,
diff --git a/core/skills/__init__.py b/core/skills/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/core/tool_registry.py b/core/tool_registry.py
index 377585e..b5e2e20 100644
--- a/core/tool_registry.py
+++ b/core/tool_registry.py
@@ -33,7 +33,7 @@ class Tool:
     metadata: Dict[str, Any] = field(default_factory=dict)
 
     def to_schema(self) -> Dict[str, Any]:
-        """Generate OpenAI/Claude compatible JSON Schema for tool calling."""
+        """Generate an Anthropic Messages API tool definition (name / description / input_schema)."""
         properties = {}
         required = []
 
@@ -56,7 +56,7 @@ class Tool:
         return {
             "name": self.name,
             "description": self.description,
-            "parameters": {
+            "input_schema": {
                 "type": "object",
                 "properties": properties,
                 "required": required,
diff --git a/tests/test_tool_registry.py b/tests/test_tool_registry.py
index 4c82df3..dc6a758 100644
--- a/tests/test_tool_registry.py
+++ b/tests/test_tool_registry.py
@@ -27,7 +27,8 @@ async def test_tool_registry_registration_and_execution():
     schemas = registry.get_schemas()
     assert len(schemas) == 1
     assert schemas[0]["name"] == "test_tool"
-    assert "order_id" in schemas[0]["parameters"]["properties"]
+    assert "order_id" in schemas[0]["input_schema"]["properties"]
+    assert "parameters" not in schemas[0]  # Anthropic shape, not OpenAI
 
     result = await registry.execute_tool("test_tool", order_id="ORD-100")
     assert result == {"order": "ORD-100", "items": 1}
@@ -50,6 +51,32 @@ async def test_question_manager_flow():
     assert q.options[0].badge == "12 AM–9 AM"
     assert not q.answered
 
-    qm.answer_question(q.question_id, "morning")
+    assert qm.list_pending() == [q]
+    assert qm.answer_question(q.question_id, "morning") is True
     assert q.answered is True
     assert q.answer == "morning"
+    assert qm.get_pending(q.question_id) is None  # cleaned up, not leaked
+    assert qm.answer_question(q.question_id, "afternoon") is False  # double-answer rejected
+
+
+@pytest.mark.asyncio
+async def test_question_manager_wait_and_answer():
+    qm = QuestionManager()
+    q = qm.create_question(prompt="Reassign?", options=["yes", "no"], allow_custom_input=False)
+
+    async def operator():
+        await asyncio.sleep(0.01)
+        qm.answer_question(q.question_id, "yes")
+
+    asyncio.create_task(operator())
+    assert await qm.wait_for_answer(q, timeout_s=1.0) == "yes"
+    assert qm.get_pending(q.question_id) is None
+
+
+@pytest.mark.asyncio
+async def test_question_manager_timeout_cleans_up():
+    qm = QuestionManager()
+    q = qm.create_question(prompt="Reassign?", options=["yes", "no"])
+    with pytest.raises(TimeoutError):
+        await qm.wait_for_answer(q, timeout_s=0.01)
+    assert qm.get_pending(q.question_id) is None