结果替代中间件允许在代理返回到调用方之前截获和修改代理的输出。 这对于内容转换、响应扩充或完全替换代理输出非常有用。
在 C# 中，可以通过修改 AgentResponse 代理运行返回的结果来替代结果：
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading;
using System.Threading.Tasks;
using Azure.AI.OpenAI;
using Azure.Identity;
using Microsoft.Agents.AI;
using Microsoft.Extensions.AI;
// Middleware that modifies the AgentResponse after the agent completes
async Task<AgentResponse> ResultOverrideMiddleware(
IEnumerable<ChatMessage> messages,
AgentSession? session,
AgentRunOptions? options,
AIAgent innerAgent,
CancellationToken cancellationToken)
{
var response = await innerAgent.RunAsync(messages, session, options, cancellationToken);
// Post-process: append a disclaimer to every assistant message
var modifiedMessages = response.Messages.Select(msg =>
{
if (msg.Role == ChatRole.Assistant && msg.Text is not null)
{
return new ChatMessage(ChatRole.Assistant,
msg.Text + "\n\n_Disclaimer: This information is AI-generated._");
}
return msg;
}).ToList();
return new AgentResponse(modifiedMessages);
}
AIAgent agent = new AzureOpenAIClient(
new Uri("https://<myresource>.openai.azure.com"),
new AzureCliCredential())
.GetChatClient("gpt-4o-mini")
.AsAIAgent(instructions: "You are a helpful weather assistant.");
var agentWithOverride = agent
.AsBuilder()
.Use(runFunc: ResultOverrideMiddleware, runStreamingFunc: null)
.Build();
Console.WriteLine(await agentWithOverride.RunAsync("What's the weather in Seattle?"));
天气覆盖中间件
此示例替代流式处理和非流式处理方案的代理结果：
# Copyright (c) Microsoft. All rights reserved.
import asyncio
import re
from collections.abc import Awaitable, Callable
from random import randint
from typing import Annotated
from agent_framework import (
AgentContext,
AgentResponse,
AgentResponseUpdate,
ChatContext,
ChatResponse,
ChatResponseUpdate,
Message,
ResponseStream,
tool,
)
from agent_framework.openai import OpenAIResponsesClient
from pydantic import Field
"""
Result Override with MiddlewareTypes (Regular and Streaming)
This sample demonstrates how to use middleware to intercept and modify function results
after execution, supporting both regular and streaming agent responses. The example shows:
- How to execute the original function first and then modify its result
- Replacing function outputs with custom messages or transformed data
- Using middleware for result filtering, formatting, or enhancement
- Detecting streaming vs non-streaming execution using context.stream
- Overriding streaming results with custom async generators
The weather override middleware lets the original weather function execute normally,
then replaces its result with a custom "perfect weather" message. For streaming responses,
it creates a custom async generator that yields the override message in chunks.
"""
# NOTE: approval_mode="never_require" is for sample brevity. Use "always_require" in production; see samples/02-agents/tools/function_tool_with_approval.py and samples/02-agents/tools/function_tool_with_approval_and_sessions.py.
@tool(approval_mode="never_require")
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."
async def weather_override_middleware(context: ChatContext, call_next: Callable[[], Awaitable[None]]) -> None:
"""Chat middleware that overrides weather results for both streaming and non-streaming cases."""
# Let the original agent execution complete first
await call_next()
# Check if there's a result to override (agent called weather function)
if context.result is not None:
# Create custom weather message
chunks = [
"due to special atmospheric conditions, ",
"all locations are experiencing perfect weather today! ",
"Temperature is a comfortable 22°C with gentle breezes. ",
"Perfect day for outdoor activities!",
]
if context.stream and isinstance(context.result, ResponseStream):
index = {"value": 0}
def _update_hook(update: ChatResponseUpdate) -> ChatResponseUpdate:
for content in update.contents or []:
if not content.text:
continue
content.text = f"Weather Advisory: [{index['value']}] {content.text}"
index["value"] += 1
return update
context.result.with_transform_hook(_update_hook)
else:
# For non-streaming: just replace with a new message
current_text = context.result.text if isinstance(context.result, ChatResponse) else ""
custom_message = f"Weather Advisory: [0] {''.join(chunks)} Original message was: {current_text}"
context.result = ChatResponse(messages=[Message(role="assistant", contents=[custom_message])])
async def validate_weather_middleware(context: ChatContext, call_next: Callable[[], Awaitable[None]]) -> None:
"""Chat middleware that simulates result validation for both streaming and non-streaming cases."""
await call_next()
validation_note = "Validation: weather data verified."
if context.result is None:
return
if context.stream and isinstance(context.result, ResponseStream):
def _append_validation_note(response: ChatResponse) -> ChatResponse:
response.messages.append(Message(role="assistant", contents=[validation_note]))
return response
context.result.with_finalizer(_append_validation_note)
elif isinstance(context.result, ChatResponse):
context.result.messages.append(Message(role="assistant", contents=[validation_note]))
async def agent_cleanup_middleware(context: AgentContext, call_next: Callable[[], Awaitable[None]]) -> None:
"""Agent middleware that validates chat middleware effects and cleans the result."""
await call_next()
if context.result is None:
return
validation_note = "Validation: weather data verified."
state = {"found_prefix": False}
def _sanitize(response: AgentResponse) -> AgentResponse:
found_prefix = state["found_prefix"]
found_validation = False
cleaned_messages: list[Message] = []
for message in response.messages:
text = message.text
if text is None:
cleaned_messages.append(message)
continue
if validation_note in text:
found_validation = True
text = text.replace(validation_note, "").strip()
if not text:
continue
if "Weather Advisory:" in text:
found_prefix = True
text = text.replace("Weather Advisory:", "")
text = re.sub(r"\[\d+\]\s*", "", text)
cleaned_messages.append(
Message(
role=message.role,
contents=[text.strip()],
author_name=message.author_name,
message_id=message.message_id,
additional_properties=message.additional_properties,
raw_representation=message.raw_representation,
)
)
if not found_prefix:
raise RuntimeError("Expected chat middleware prefix not found in agent response.")
if not found_validation:
raise RuntimeError("Expected validation note not found in agent response.")
cleaned_messages.append(Message(role="assistant", contents=[" Agent: OK"]))
response.messages = cleaned_messages
return response
if context.stream and isinstance(context.result, ResponseStream):
def _clean_update(update: AgentResponseUpdate) -> AgentResponseUpdate:
for content in update.contents or []:
if not content.text:
continue
text = content.text
if "Weather Advisory:" in text:
state["found_prefix"] = True
text = text.replace("Weather Advisory:", "")
text = re.sub(r"\[\d+\]\s*", "", text)
content.text = text
return update
context.result.with_transform_hook(_clean_update)
context.result.with_finalizer(_sanitize)
elif isinstance(context.result, AgentResponse):
context.result = _sanitize(context.result)
async def main() -> None:
"""Example demonstrating result override with middleware for both streaming and non-streaming."""
print("=== Result Override MiddlewareTypes Example ===")
# For authentication, run `az login` command in terminal or replace AzureCliCredential with preferred
# authentication option.
agent = OpenAIResponsesClient(
middleware=[validate_weather_middleware, weather_override_middleware],
).as_agent(
name="WeatherAgent",
instructions="You are a helpful weather assistant. Use the weather tool to get current conditions.",
tools=get_weather,
middleware=[agent_cleanup_middleware],
)
# Non-streaming example
print("\n--- Non-streaming Example ---")
query = "What's the weather like in Seattle?"
print(f"User: {query}")
result = await agent.run(query)
print(f"Agent: {result}")
# Streaming example
print("\n--- Streaming Example ---")
query = "What's the weather like in Portland?"
print(f"User: {query}")
print("Agent: ", end="", flush=True)
response = agent.run(query, stream=True)
async for chunk in response:
if chunk.text:
print(chunk.text, end="", flush=True)
print("\n")
print(f"Final Result: {(await response.get_final_response()).text}")
if __name__ == "__main__":
asyncio.run(main())
验证中间件
此示例验证代理结果，并根据需要对其进行修改：
# Copyright (c) Microsoft. All rights reserved.
import asyncio
import re
from collections.abc import Awaitable, Callable
from random import randint
from typing import Annotated
from agent_framework import (
AgentContext,
AgentResponse,
AgentResponseUpdate,
ChatContext,
ChatResponse,
ChatResponseUpdate,
Message,
ResponseStream,
tool,
)
from agent_framework.openai import OpenAIResponsesClient
from pydantic import Field
"""
Result Override with MiddlewareTypes (Regular and Streaming)
This sample demonstrates how to use middleware to intercept and modify function results
after execution, supporting both regular and streaming agent responses. The example shows:
- How to execute the original function first and then modify its result
- Replacing function outputs with custom messages or transformed data
- Using middleware for result filtering, formatting, or enhancement
- Detecting streaming vs non-streaming execution using context.stream
- Overriding streaming results with custom async generators
The weather override middleware lets the original weather function execute normally,
then replaces its result with a custom "perfect weather" message. For streaming responses,
it creates a custom async generator that yields the override message in chunks.
"""
# NOTE: approval_mode="never_require" is for sample brevity. Use "always_require" in production; see samples/02-agents/tools/function_tool_with_approval.py and samples/02-agents/tools/function_tool_with_approval_and_sessions.py.
@tool(approval_mode="never_require")
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."
async def weather_override_middleware(context: ChatContext, call_next: Callable[[], Awaitable[None]]) -> None:
"""Chat middleware that overrides weather results for both streaming and non-streaming cases."""
# Let the original agent execution complete first
await call_next()
# Check if there's a result to override (agent called weather function)
if context.result is not None:
# Create custom weather message
chunks = [
"due to special atmospheric conditions, ",
"all locations are experiencing perfect weather today! ",
"Temperature is a comfortable 22°C with gentle breezes. ",
"Perfect day for outdoor activities!",
]
if context.stream and isinstance(context.result, ResponseStream):
index = {"value": 0}
def _update_hook(update: ChatResponseUpdate) -> ChatResponseUpdate:
for content in update.contents or []:
if not content.text:
continue
content.text = f"Weather Advisory: [{index['value']}] {content.text}"
index["value"] += 1
return update
context.result.with_transform_hook(_update_hook)
else:
# For non-streaming: just replace with a new message
current_text = context.result.text if isinstance(context.result, ChatResponse) else ""
custom_message = f"Weather Advisory: [0] {''.join(chunks)} Original message was: {current_text}"
context.result = ChatResponse(messages=[Message(role="assistant", contents=[custom_message])])
async def validate_weather_middleware(context: ChatContext, call_next: Callable[[], Awaitable[None]]) -> None:
"""Chat middleware that simulates result validation for both streaming and non-streaming cases."""
await call_next()
validation_note = "Validation: weather data verified."
if context.result is None:
return
if context.stream and isinstance(context.result, ResponseStream):
def _append_validation_note(response: ChatResponse) -> ChatResponse:
response.messages.append(Message(role="assistant", contents=[validation_note]))
return response
context.result.with_finalizer(_append_validation_note)
elif isinstance(context.result, ChatResponse):
context.result.messages.append(Message(role="assistant", contents=[validation_note]))
async def agent_cleanup_middleware(context: AgentContext, call_next: Callable[[], Awaitable[None]]) -> None:
"""Agent middleware that validates chat middleware effects and cleans the result."""
await call_next()
if context.result is None:
return
validation_note = "Validation: weather data verified."
state = {"found_prefix": False}
def _sanitize(response: AgentResponse) -> AgentResponse:
found_prefix = state["found_prefix"]
found_validation = False
cleaned_messages: list[Message] = []
for message in response.messages:
text = message.text
if text is None:
cleaned_messages.append(message)
continue
if validation_note in text:
found_validation = True
text = text.replace(validation_note, "").strip()
if not text:
continue
if "Weather Advisory:" in text:
found_prefix = True
text = text.replace("Weather Advisory:", "")
text = re.sub(r"\[\d+\]\s*", "", text)
cleaned_messages.append(
Message(
role=message.role,
contents=[text.strip()],
author_name=message.author_name,
message_id=message.message_id,
additional_properties=message.additional_properties,
raw_representation=message.raw_representation,
)
)
if not found_prefix:
raise RuntimeError("Expected chat middleware prefix not found in agent response.")
if not found_validation:
raise RuntimeError("Expected validation note not found in agent response.")
cleaned_messages.append(Message(role="assistant", contents=[" Agent: OK"]))
response.messages = cleaned_messages
return response
if context.stream and isinstance(context.result, ResponseStream):
def _clean_update(update: AgentResponseUpdate) -> AgentResponseUpdate:
for content in update.contents or []:
if not content.text:
continue
text = content.text
if "Weather Advisory:" in text:
state["found_prefix"] = True
text = text.replace("Weather Advisory:", "")
text = re.sub(r"\[\d+\]\s*", "", text)
content.text = text
return update
context.result.with_transform_hook(_clean_update)
context.result.with_finalizer(_sanitize)
elif isinstance(context.result, AgentResponse):
context.result = _sanitize(context.result)
async def main() -> None:
"""Example demonstrating result override with middleware for both streaming and non-streaming."""
print("=== Result Override MiddlewareTypes Example ===")
# For authentication, run `az login` command in terminal or replace AzureCliCredential with preferred
# authentication option.
agent = OpenAIResponsesClient(
middleware=[validate_weather_middleware, weather_override_middleware],
).as_agent(
name="WeatherAgent",
instructions="You are a helpful weather assistant. Use the weather tool to get current conditions.",
tools=get_weather,
middleware=[agent_cleanup_middleware],
)
# Non-streaming example
print("\n--- Non-streaming Example ---")
query = "What's the weather like in Seattle?"
print(f"User: {query}")
result = await agent.run(query)
print(f"Agent: {result}")
# Streaming example
print("\n--- Streaming Example ---")
query = "What's the weather like in Portland?"
print(f"User: {query}")
print("Agent: ", end="", flush=True)
response = agent.run(query, stream=True)
async for chunk in response:
if chunk.text:
print(chunk.text, end="", flush=True)
print("\n")
print(f"Final Result: {(await response.get_final_response()).text}")
if __name__ == "__main__":
asyncio.run(main())