diff --git a/test_langgraph/__main__.py b/test_langgraph/__main__.py
index 504ae04..2f1d7f2 100644
--- a/test_langgraph/__main__.py
+++ b/test_langgraph/__main__.py
@@ -32,9 +32,15 @@ def create_model():
     llm.bind_tools(tools=available_tools )
     return create_react_agent(llm, tools=available_tools )
 
+SYSTEM_MESSAGE = '''
+You are a useful assistant with access to built in system tools.
+Format responses as markdown.
+Provide links when available.
+'''
+
 def main():
     logging.basicConfig(level='INFO')
-    messages = [SystemMessage("You are a useful assistant with access to built in system tools.")]
+    messages = [SystemMessage(SYSTEM_MESSAGE)]
     llm = create_model()
     prev_idx = 0
     while True:
@@ -49,7 +55,7 @@ def main():
         })
         messages = result['messages']
         for msg in messages[prev_idx:]:
-            print(f'{msg.type}: {msg.content}')
+            print(msg.pretty_repr())
             del msg
         prev_idx = len(messages)
 
diff --git a/test_langgraph/tools.py b/test_langgraph/tools.py
index a0837de..9c22aa1 100644
--- a/test_langgraph/tools.py
+++ b/test_langgraph/tools.py
@@ -1,12 +1,18 @@
 from langchain_core.tools import tool
 
 import requests_cache
+import dataclasses
 import clients
 from typing import get_type_hints, List, Dict, Any
 from collections.abc import Iterator
 import logging
 import secret_loader
 
+try:
+    import pycountry.db
+except ImportError:
+    pycountry = None
+
 logger = logging.getLogger(__name__)
 
 
@@ -17,6 +23,29 @@ def search(query: str):
         return "It's 60 degrees and foggy."
     return "It's 90 degrees and sunny."
 
+def dataclasses_to_json(data):
+    if pycountry and isinstance(data, pycountry.db.Country):
+        return data.alpha_3
+    if isinstance(data, list | tuple):
+        return [dataclasses_to_json(d) for d in data]
+    if dataclasses.is_dataclass(data):
+        result = {}
+        for field in dataclasses.fields(data):
+            result[field.name] = dataclasses_to_json(getattr(data,field.name))
+        return result
+    return data
+
+
+assert dataclasses_to_json([1,2,3]) == [1,2,3]
+
+
+RETURN_FORMATS = {
+        'raw_python': lambda x: x,
+        'json': dataclasses_to_json,
+}
+
+RETURN_FORMAT = 'json'
+
 def wrap_method(class_, method):
     logger.info("Wrapping %s.%s", class_.__name__, method.__name__)
     is_iterator = str(method.__annotations__.get('return', '')).startswith('collections.abc.Iterator')
@@ -26,10 +55,14 @@ def wrap_method(class_, method):
             logger.warning("Silently converting from dict to plain value!")
             input_value = next(input_value.values())
         logger.info("AI called %s.%s(%s)", class_.__name__, method.__name__, repr(input_value))
-        result = method(input_value)
-        if is_iterator:
-            result = list(result)
-        return result
+        try:
+            result = method(input_value)
+            if is_iterator:
+                result = list(result)
+            return RETURN_FORMATS[RETURN_FORMAT](result)
+        except:
+            logger.exception("AI invocation of %s.%s(%s) failed!", class_.__name__, method.__name__, repr(input_value))
+            raise
 
     wrapper.__name__ = f'{class_.__name__}.{method.__name__}'
     wrapper.__doc__ = method.__doc__