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agent-framework/python
T
claude89757 db283cd396 Python: Fix MCP tool result serialization for list[TextContent] (#2523)
* Fix MCP tool result serialization for list[TextContent]

When MCP tools return results containing list[TextContent], they were
incorrectly serialized to object repr strings like:
'[<agent_framework._types.TextContent object at 0x...>]'

This fix properly extracts text content from list items by:
1. Checking if items have a 'text' attribute (TextContent)
2. Using model_dump() for items that support it
3. Falling back to str() for other types
4. Joining single items as plain text, multiple items as JSON array

Fixes #2509

* Address PR review feedback for MCP tool result serialization

- Extract serialize_content_result() to shared _utils.py
- Fix logic: use texts[0] instead of join for single item
- Add type annotation: texts: list[str] = []
- Return empty string for empty list instead of '[]'
- Move import json to file top level
- Add comprehensive unit tests for serialization

* Address PR review feedback: fix type checking and double serialization

- Add isinstance(item.text, str) check to ensure text attribute is a string
- Fix double-serialization issue by keeping model_dump results as dicts
  until final json.dumps (removes escaped JSON strings in arrays)
- Improve docstring with detailed return value documentation
- Add test for non-string text attribute handling
- Add tests for list type tool results in _events.py path

* Simplify PR: minimal changes to fix MCP tool result serialization

Addresses reviewer feedback about excessive refactoring:
- Reset _events.py to original structure
- Only add import and use serialize_content_result in one location
- All review comments addressed in serialize_content_result():
  - Added isinstance(item.text, str) check
  - Use model_dump(mode="json") to avoid double-serialization
  - Improved docstring with explicit return value documentation
  - Empty list returns "" instead of "[]"

* Refactor: Move MCP TextContent serialization to core prepare_function_call_results

Per reviewer feedback, moved the TextContent serialization logic from
ag-ui's serialize_content_result to the core package's
prepare_function_call_results function.

Changes:
- Added handling for objects with 'text' attribute (like MCP TextContent)
  in _prepare_function_call_results_as_dumpable
- Removed serialize_content_result from ag-ui/_utils.py
- Updated _events.py and _message_adapters.py to use
  prepare_function_call_results from core package
- Updated tests to match the core function's behavior

* Fix failing tests for prepare_function_call_results behavior

- test_tool_result_with_none: Update expected value to 'null' (JSON serialization of None)
- test_tool_result_with_model_dump_objects: Use Pydantic BaseModel instead of plain class

* Fix B903 linter error: Convert MockTextContent to dataclass

The ruff linter was reporting B903 (class could be dataclass or namedtuple)
for the MockTextContent test helper classes. This commit converts them to
dataclasses to satisfy the linter check.
db283cd396 · 2026-01-07 00:47:26 +00:00
History
..
2026-01-06 22:57:54 +00:00
2025-10-01 11:54:26 +00:00
2025-11-14 02:56:44 +00:00
2026-01-07 09:34:02 +09:00

Get Started with Microsoft Agent Framework for Python Developers

Quick Install

We recommend two common installation paths depending on your use case.

1. Development mode

If you are exploring or developing locally, install the entire framework with all sub-packages:

pip install agent-framework --pre

This installs the core and every integration package, making sure that all features are available without additional steps. The --pre flag is required while Agent Framework is in preview. This is the simplest way to get started.

2. Selective install

If you only need specific integrations, you can install at a more granular level. This keeps dependencies lighter and focuses on what you actually plan to use. Some examples:

# Core only
# includes Azure OpenAI and OpenAI support by default
# also includes workflows and orchestrations
pip install agent-framework-core --pre

# Core + Azure AI integration
pip install agent-framework-azure-ai --pre

# Core + Microsoft Copilot Studio integration
pip install agent-framework-copilotstudio --pre

# Core + both Microsoft Copilot Studio and Azure AI integration
pip install agent-framework-microsoft agent-framework-azure-ai --pre

This selective approach is useful when you know which integrations you need, and it is the recommended way to set up lightweight environments.

Supported Platforms:

  • Python: 3.10+
  • OS: Windows, macOS, Linux

1. Setup API Keys

Set as environment variables, or create a .env file at your project root:

OPENAI_API_KEY=sk-...
OPENAI_CHAT_MODEL_ID=...
...
AZURE_OPENAI_API_KEY=...
AZURE_OPENAI_ENDPOINT=...
AZURE_OPENAI_CHAT_DEPLOYMENT_NAME=...
...
AZURE_AI_PROJECT_ENDPOINT=...
AZURE_AI_MODEL_DEPLOYMENT_NAME=...

You can also override environment variables by explicitly passing configuration parameters to the chat client constructor:

from agent_framework.azure import AzureOpenAIChatClient

chat_client = AzureOpenAIChatClient(
    api_key='',
    endpoint='',
    deployment_name='',
    api_version='',
)

See the following setup guide for more information.

2. Create a Simple Agent

Create agents and invoke them directly:

import asyncio
from agent_framework import ChatAgent
from agent_framework.openai import OpenAIChatClient

async def main():
    agent = ChatAgent(
        chat_client=OpenAIChatClient(),
        instructions="""
        1) A robot may not injure a human being...
        2) A robot must obey orders given it by human beings...
        3) A robot must protect its own existence...

        Give me the TLDR in exactly 5 words.
        """
    )

    result = await agent.run("Summarize the Three Laws of Robotics")
    print(result)

asyncio.run(main())
# Output: Protect humans, obey, self-preserve, prioritized.

3. Directly Use Chat Clients (No Agent Required)

You can use the chat client classes directly for advanced workflows:

import asyncio
from agent_framework import ChatMessage
from agent_framework.openai import OpenAIChatClient

async def main():
    client = OpenAIChatClient()

    messages = [
        ChatMessage(role="system", text="You are a helpful assistant."),
        ChatMessage(role="user", text="Write a haiku about Agent Framework.")
    ]

    response = await client.get_response(messages)
    print(response.messages[0].text)

    """
    Output:

    Agents work in sync,
    Framework threads through each task—
    Code sparks collaboration.
    """

asyncio.run(main())

4. Build an Agent with Tools and Functions

Enhance your agent with custom tools and function calling:

import asyncio
from typing import Annotated
from random import randint
from pydantic import Field
from agent_framework import ChatAgent
from agent_framework.openai import OpenAIChatClient


def get_weather(
    location: Annotated[str, Field(description="The location to get the weather for.")],
) -> str:
    """Get the weather for a given location."""
    conditions = ["sunny", "cloudy", "rainy", "stormy"]
    return f"The weather in {location} is {conditions[randint(0, 3)]} with a high of {randint(10, 30)}°C."


def get_menu_specials() -> str:
    """Get today's menu specials."""
    return """
    Special Soup: Clam Chowder
    Special Salad: Cobb Salad
    Special Drink: Chai Tea
    """


async def main():
    agent = ChatAgent(
        chat_client=OpenAIChatClient(),
        instructions="You are a helpful assistant that can provide weather and restaurant information.",
        tools=[get_weather, get_menu_specials]
    )

    response = await agent.run("What's the weather in Amsterdam and what are today's specials?")
    print(response)

    """
    Output:
    The weather in Amsterdam is sunny with a high of 22°C. Today's specials include
    Clam Chowder soup, Cobb Salad, and Chai Tea as the special drink.
    """

if __name__ == "__main__":
    asyncio.run(main())

You can explore additional agent samples here.

5. Multi-Agent Orchestration

Coordinate multiple agents to collaborate on complex tasks using orchestration patterns:

import asyncio
from agent_framework import ChatAgent
from agent_framework.openai import OpenAIChatClient


async def main():
    # Create specialized agents
    writer = ChatAgent(
        chat_client=OpenAIChatClient(),
        name="Writer",
        instructions="You are a creative content writer. Generate and refine slogans based on feedback."
    )

    reviewer = ChatAgent(
        chat_client=OpenAIChatClient(),
        name="Reviewer",
        instructions="You are a critical reviewer. Provide detailed feedback on proposed slogans."
    )

    # Sequential workflow: Writer creates, Reviewer provides feedback
    task = "Create a slogan for a new electric SUV that is affordable and fun to drive."

    # Step 1: Writer creates initial slogan
    initial_result = await writer.run(task)
    print(f"Writer: {initial_result}")

    # Step 2: Reviewer provides feedback
    feedback_request = f"Please review this slogan: {initial_result}"
    feedback = await reviewer.run(feedback_request)
    print(f"Reviewer: {feedback}")

    # Step 3: Writer refines based on feedback
    refinement_request = f"Please refine this slogan based on the feedback: {initial_result}\nFeedback: {feedback}"
    final_result = await writer.run(refinement_request)
    print(f"Final Slogan: {final_result}")

    # Example Output:
    # Writer: "Charge Forward: Affordable Adventure Awaits!"
    # Reviewer: "Good energy, but 'Charge Forward' is overused in EV marketing..."
    # Final Slogan: "Power Up Your Adventure: Premium Feel, Smart Price!"

if __name__ == "__main__":
    asyncio.run(main())

For more advanced orchestration patterns including Sequential, GroupChat, Concurrent, Magentic, and Handoff orchestrations, see the orchestration samples.

More Examples & Samples

Agent Framework Documentation