Python: Add concrete AGUIChatClient (#2072)

* Add concrete AGUIChatClient

* Update logging docstrings and conventions

* PR feedback

* Updates to support client-side tool calls

python/packages/ag-ui/tests/test_orchestrators.py

@@ -0,0 +1,82 @@
+"""Tests for AG-UI orchestrators."""
+
+from collections.abc import AsyncGenerator
+from types import SimpleNamespace
+from typing import Any
+
+from agent_framework import AgentRunResponseUpdate, TextContent, ai_function
+from agent_framework._tools import FunctionInvocationConfiguration
+
+from agent_framework_ag_ui._agent import AgentConfig
+from agent_framework_ag_ui._orchestrators import DefaultOrchestrator, ExecutionContext
+
+
+@ai_function
+def server_tool() -> str:
+    """Server-executable tool."""
+    return "server"
+
+
+class DummyAgent:
+    """Minimal agent stub to capture run_stream parameters."""
+
+    def __init__(self) -> None:
+        self.chat_options = SimpleNamespace(tools=[server_tool], response_format=None)
+        self.tools = [server_tool]
+        self.chat_client = SimpleNamespace(
+            function_invocation_configuration=FunctionInvocationConfiguration(),
+        )
+        self.seen_tools: list[Any] | None = None
+
+    async def run_stream(
+        self,
+        messages: list[Any],
+        *,
+        thread: Any,
+        tools: list[Any] | None = None,
+    ) -> AsyncGenerator[AgentRunResponseUpdate, None]:
+        self.seen_tools = tools
+        yield AgentRunResponseUpdate(contents=[TextContent(text="ok")], role="assistant")
+
+
+async def test_default_orchestrator_merges_client_tools() -> None:
+    """Client tool declarations are merged with server tools before running agent."""
+
+    agent = DummyAgent()
+    orchestrator = DefaultOrchestrator()
+
+    input_data = {
+        "messages": [
+            {
+                "role": "user",
+                "content": [{"type": "input_text", "text": "Hello"}],
+            }
+        ],
+        "tools": [
+            {
+                "name": "get_weather",
+                "description": "Client weather lookup.",
+                "parameters": {
+                    "type": "object",
+                    "properties": {"location": {"type": "string"}},
+                    "required": ["location"],
+                },
+            }
+        ],
+    }
+
+    context = ExecutionContext(
+        input_data=input_data,
+        agent=agent,
+        config=AgentConfig(),
+    )
+
+    events = []
+    async for event in orchestrator.run(context):
+        events.append(event)
+
+    assert agent.seen_tools is not None
+    tool_names = [getattr(tool, "name", "?") for tool in agent.seen_tools]
+    assert "server_tool" in tool_names
+    assert "get_weather" in tool_names
+    assert agent.chat_client.function_invocation_configuration.additional_tools