GPT-4o & HITL Workflow Nodes
New Defaults and Capabilities
GPT-4o is now the default generative engine for Copilot Studio orchestration. It provides significantly faster function-calling and deeper reasoning for dynamic tool selection.
Additionally, Claude 3.5 Sonnet is now fully supported as an optional model specifically optimized for Computer-Using Agents (CUAs), given its superior visual reasoning capabilities. Computer-Using Agents reached General Availability in May 2026, enabling production-ready agentic RPA with vision-based UI automation.
Human-in-the-Loop (HITL) Forms
The most requested feature of 2025 is now GA: HITL Dynamic Workflow Nodes. When an agent reaches a high-stakes decision point, it can automatically pause execution and trigger a structured Outlook Adaptive Card Form.
The human manager reviews the agent's proposed action in Outlook, modifies the parameters if necessary, and clicks 'Approve'. The agent instantly wakes up and resumes the workflow with the human's input.
April 2026 GA Announcements
| Feature | Status | Impact |
|---|---|---|
| Copilot Studio Multi-Agent Coordination | GA | Orchestrate multiple specialized agents from a single Copilot Studio environment — each with distinct knowledge, tools, and permission scopes. |
| Work IQ | GA | AI-powered process mining that discovers automation opportunities from employee work patterns across M365 — surfaces bottlenecks and suggests agents. |
| Evaluation APIs | Public Preview | Programmatic agent quality assessment — score agents on groundedness, coherence, and safety before production deployment. |
| OpenAI o1 Integration | Preview | OpenAI o1 available as an optional orchestration model with 1M token context for deep multi-document agentic workflows. |
Microsoft Build 2026 (June 2–3)
Microsoft Build 2026 expanded on Wave 1 with the Unified Workflows Designer — a single canvas for authoring cloud flows, desktop flows, and agent flows — and enhanced Copilot Studio capabilities including deeper A2A protocol integration and real-time agent analytics dashboards.