feat: enhance visualization functions with optional type hints and improved handling of agents and handoffs

Author: MartinEBravo

src/agents/extensions/visualization.py

@@ -1,6 +1,7 @@
 import graphviz
 
 from agents import Agent
+from agents.handoffs import Handoff
 
 
 def get_main_graph(agent: Agent) -> str:
@@ -29,7 +30,9 @@ def get_main_graph(agent: Agent) -> str:
     return "".join(parts)
 
 
-def get_all_nodes(agent: Agent, parent: Agent = None) -> str:
+from typing import Optional
+
+def get_all_nodes(agent: Agent, parent: Optional[Agent] = None) -> str:
     """
     Recursively generates the nodes for the given agent and its handoffs in DOT format.
 
@@ -47,25 +50,29 @@ def get_all_nodes(agent: Agent, parent: Agent = None) -> str:
             "fillcolor=lightyellow, width=1.5, height=0.8];"
         )
 
-    # Smaller tools (ellipse, green)
     for tool in agent.tools:
         parts.append(
             f'"{tool.name}" [label="{tool.name}", shape=ellipse, style=filled, '
             f"fillcolor=lightgreen, width=0.5, height=0.3];"
         )
 
-    # Bigger handoffs (rounded box, yellow)
     for handoff in agent.handoffs:
-        parts.append(
-            f'"{handoff.name}" [label="{handoff.name}", shape=box, style=filled, style=rounded, '
-            f"fillcolor=lightyellow, width=1.5, height=0.8];"
-        )
-        parts.append(get_all_nodes(handoff))
+        if isinstance(handoff, Handoff):
+            parts.append(
+                f'"{handoff.agent_name}" [label="{handoff.agent_name}", shape=box, style=filled, style=rounded, '
+                f"fillcolor=lightyellow, width=1.5, height=0.8];"
+            )
+        if isinstance(handoff, Agent):
+            parts.append(
+                f'"{handoff.name}" [label="{handoff.name}", shape=box, style=filled, style=rounded, '
+                f"fillcolor=lightyellow, width=1.5, height=0.8];"
+            )
+            parts.append(get_all_nodes(handoff))
 
     return "".join(parts)
 
 
-def get_all_edges(agent: Agent, parent: Agent = None) -> str:
+def get_all_edges(agent: Agent, parent: Optional[Agent] = None) -> str:
     """
     Recursively generates the edges for the given agent and its handoffs in DOT format.
 
@@ -92,14 +99,20 @@ def get_all_edges(agent: Agent, parent: Agent = None) -> str:
         "{agent.name}" -> "__end__";""")
 
     for handoff in agent.handoffs:
-        parts.append(f"""
-        "{agent.name}" -> "{handoff.name}";""")
-        parts.append(get_all_edges(handoff, agent))
+        if isinstance(handoff, Handoff):
+            parts.append(f"""
+            "{agent.name}" -> "{handoff.agent_name}";""")
+        if isinstance(handoff, Agent):
+            parts.append(f"""
+            "{agent.name}" -> "{handoff.name}";""")
+            parts.append(get_all_edges(handoff, agent))
 
     return "".join(parts)
 
 
-def draw_graph(agent: Agent, filename: str = None) -> graphviz.Source:
+from typing import Optional
+
+def draw_graph(agent: Agent, filename: Optional[str] = None) -> graphviz.Source:
     """
     Draws the graph for the given agent and optionally saves it as a PNG file.