Upgrade to agent_framework 1.0.0 — HandoffBuilder → WorkflowBuilder

[JasonHaley]

Summary

Refactor the application from the HandoffBuilder orchestration pattern (event-streaming with pending requests) to the new WorkflowBuilder pattern (structured output with switch-case routing) to upgrade to agent_framework 1.0.0.

Key Changes Needed

Architecture Change

• HandoffBuilder → WorkflowBuilder: Replace event-streaming handoff with stateless switch-case routing using structured output from a classifier agent
• Each workflow.run(question) is independent and stateless — no more pending request/response loops

Classifier Agent Rewrite

• Add Pydantic models (ClassifyResult, ClassifiedQuery) for structured output
• Add @executor function (extract_category) to parse classifier JSON and route downstream
• Add QueryBridge executor class to convert ClassifiedQuery → plain string for specialist agents
• Use response_format to enforce structured JSON output

API Renames (all 9 specialist agents)

Old (current)	New (1.0.0)
ChatAgent	Agent
@ai_function	@tool
agent_framework.azure.AzureOpenAIChatClient	agent_framework.openai.OpenAIChatClient
OpenAIChatOptions	(removed)

Auth Model Change

• Switch from API key-based OpenAI auth to DefaultAzureCredential with token provider
• Remove openai_api_key from config
• Use azure_ad_token_provider in AzureOpenAI client

Workflow Handlers

• Replace drain_events / handle_workflow_events (event-streaming) with simple handle_workflow_result(result: WorkflowRunResult)

main.py Rewrite

• Build workflow with edges: classifier → extract_category → [switch_case] → bridges → specialist agents
• Include all 9 agent categories (yes_no, semantic_search, count, difference, intersection, multi_hop, comparative, ordinal, superlative)
• Simplify test loop — no more pending request handling

Agents Retained

• ordinal_agent and superlative_agent are unique to this repo and will be upgraded to the new API patterns (not deleted)

Reference

Target codebase: https://github.com/AgentFrameworkDev/agent-framework-dev-day/tree/main/labs/python/lab3-agentic-rag/solution

Files to Modify

• src/config/azure_config.py
• src/services/search_service.py
• src/agents/classifier_agent.py (major rewrite)
• src/agents/semantic_search_agent.py
• src/agents/yes_no_agent.py
• src/agents/count_agent.py
• src/agents/difference_agent.py
• src/agents/intersection_agent.py
• src/agents/multi_hop_agent.py
• src/agents/comparative_agent.py
• src/agents/ordinal_agent.py
• src/agents/superlative_agent.py
• src/agents/agent_factory.py
• src/agents/__init__.py
• src/workflows/workflow_handlers.py
• src/workflows/__init__.py
• src/main.py