Python: [BREAKING] Types API Review improvements (#3647)

* Replace Role and FinishReason classes with NewType + Literal

- Remove EnumLike metaclass from _types.py
- Replace Role class with NewType('Role', str) + RoleLiteral
- Replace FinishReason class with NewType('FinishReason', str) + FinishReasonLiteral
- Update all usages across codebase to use string literals
- Remove .value access patterns (direct string comparison now works)
- Add backward compatibility for legacy dict serialization format
- Update tests to reflect new string-based types

Addresses #3591, #3615

* Simplify ChatResponse and AgentResponse type hints (#3592)

- Remove overloads from ChatResponse.__init__
- Remove text parameter from ChatResponse.__init__
- Remove | dict[str, Any] from finish_reason and usage_details params
- Remove **kwargs from AgentResponse.__init__
- Both now accept ChatMessage | Sequence[ChatMessage] | None for messages
- Update docstrings and examples to reflect changes
- Fix tests that were using removed kwargs
- Fix Role type hint usage in ag-ui utils

* Remove text parameter from ChatResponseUpdate and AgentResponseUpdate (#3597)

- Remove text parameter from ChatResponseUpdate.__init__
- Remove text parameter from AgentResponseUpdate.__init__
- Remove **kwargs from both update classes
- Simplify contents parameter type to Sequence[Content] | None
- Update all usages to use contents=[Content.from_text(...)] pattern
- Fix imports in test files
- Update docstrings and examples

* Rename from_chat_response_updates to from_updates (#3593)

- ChatResponse.from_chat_response_updates → ChatResponse.from_updates
- ChatResponse.from_chat_response_generator → ChatResponse.from_update_generator
- AgentResponse.from_agent_run_response_updates → AgentResponse.from_updates

* Remove try_parse_value method from ChatResponse and AgentResponse (#3595)

- Remove try_parse_value method from ChatResponse
- Remove try_parse_value method from AgentResponse
- Remove try_parse_value calls from from_updates and from_update_generator methods
- Update samples to use try/except with response.value instead
- Update tests to use response.value pattern
- Users should now use response.value with try/except for safe parsing

* Add agent_id to AgentResponse and clarify author_name documentation (#3596)

- Add agent_id parameter to AgentResponse class
- Document that author_name is on ChatMessage objects, not responses
- Update ChatResponse docstring with author_name note
- Update AgentResponse docstring with author_name note

* Simplify ChatMessage.__init__ signature (#3618)

- Make contents a positional argument accepting Sequence[Content | str]
- Auto-convert strings in contents to TextContent
- Remove overloads, keep text kwarg for backward compatibility with serialization
- Update _parse_content_list to handle string items
- Update all usages across codebase to use new format: ChatMessage("role", ["text"])

* Allow Content as input on run and get_response

- Update prepare_messages and normalize_messages to accept Content
- Update type signatures in _agents.py and _clients.py
- Add tests for Content input handling

* Fix ChatMessage usage across packages and samples

Update all remaining ChatMessage(role=..., text=...) to use new
ChatMessage('role', ['text']) signature.

* Fix Role string usage and response format parsing

- Fix redis provider: remove .value access on string literals
- Fix durabletask ensure_response_format: set _response_format before accessing .value

* Fix ollama .value and ai_model_id issues, handle None in content list

- Fix ollama _chat_client: remove .value on string literals
- Fix ollama _chat_client: rename ai_model_id to model_id
- Fix _parse_content_list: skip None values gracefully

* Fix A2AAgent type signature to include Content

* Fix Role/FinishReason NewType dict annotations and improve test coverage to 95%

* Fix mypy errors for Role/FinishReason NewType usage

* Fix Role.TOOL and Role.ASSISTANT usage in _orchestrator_helpers.py

* Fix Role NewType usage in durabletask _models.py

python/samples/getting_started/devui/fanout_workflow/workflow.py

@@ -25,7 +25,6 @@ from agent_framework import (
     WorkflowBuilder,
     WorkflowContext,
     handler,
-    tool,
 )
 from pydantic import BaseModel, Field
 from typing_extensions import Never

python/samples/getting_started/devui/foundry_agent/agent.py

@@ -8,12 +8,12 @@ Make sure to run 'az login' before starting devui.
 import os
 from typing import Annotated
 
-from agent_framework import ChatAgent
-from agent_framework import tool
+from agent_framework import ChatAgent, tool
 from agent_framework.azure import AzureAIAgentClient
 from azure.identity.aio import AzureCliCredential
 from pydantic import Field
 
+
 # NOTE: approval_mode="never_require" is for sample brevity. Use "always_require" in production; see samples/getting_started/tools/function_tool_with_approval.py and samples/getting_started/tools/function_tool_with_approval_and_threads.py.
 @tool(approval_mode="never_require")
 def get_weather(
@@ -24,6 +24,7 @@ def get_weather(
     temperature = 22
     return f"The weather in {location} is {conditions[0]} with a high of {temperature}°C."
 
+
 @tool(approval_mode="never_require")
 def get_forecast(
     location: Annotated[str, Field(description="The location to get the forecast for.")],

python/samples/getting_started/devui/in_memory_mode.py

@@ -10,8 +10,7 @@ import logging
 import os
 from typing import Annotated
 
-from agent_framework import ChatAgent, Executor, WorkflowBuilder, WorkflowContext, handler
-from agent_framework import tool
+from agent_framework import ChatAgent, Executor, WorkflowBuilder, WorkflowContext, handler, tool
 from agent_framework.azure import AzureOpenAIChatClient
 from agent_framework.devui import serve
 from typing_extensions import Never
@@ -29,6 +28,7 @@ def get_weather(
     temperature = 53
     return f"The weather in {location} is {conditions[0]} with a high of {temperature}°C."
 
+
 @tool(approval_mode="never_require")
 def get_time(
     timezone: Annotated[str, "The timezone to get time for."] = "UTC",

python/samples/getting_started/devui/spam_workflow/workflow.py

@@ -27,7 +27,6 @@ from agent_framework import (
     WorkflowContext,
     handler,
     response_handler,
-    tool,
 )
 from pydantic import BaseModel, Field
 from typing_extensions import Never

python/samples/getting_started/devui/weather_agent_azure/agent.py

@@ -14,10 +14,9 @@ from agent_framework import (
     ChatResponseUpdate,
     Content,
     FunctionInvocationContext,
-    Role,
-    tool,
     chat_middleware,
     function_middleware,
+    tool,
 )
 from agent_framework.azure import AzureOpenAIChatClient
 from agent_framework_devui import register_cleanup
@@ -43,7 +42,7 @@ async def security_filter_middleware(
 
     # Check only the last message (most recent user input)
     last_message = context.messages[-1] if context.messages else None
-    if last_message and last_message.role == Role.USER and last_message.text:
+    if last_message and last_message.role == "user" and last_message.text:
         message_lower = last_message.text.lower()
         for term in blocked_terms:
             if term in message_lower:
@@ -58,7 +57,7 @@ async def security_filter_middleware(
                     async def blocked_stream() -> AsyncIterable[ChatResponseUpdate]:
                         yield ChatResponseUpdate(
                             contents=[Content.from_text(text=error_message)],
-                            role=Role.ASSISTANT,
+                            role="assistant",
                         )
 
                     context.result = blocked_stream()
@@ -67,7 +66,7 @@ async def security_filter_middleware(
                     context.result = ChatResponse(
                         messages=[
                             ChatMessage(
-                                role=Role.ASSISTANT,
+                                role="assistant",
                                 text=error_message,
                             )
                         ]