If You’ve Ever Tried to Build a Conversational App, You Know the Struggle

Let’s face it: creating a conversational app that feels native to your users is harder than it looks. You’re juggling chatbot logic, UI consistency, and data flows—all while trying to meet deadlines. What if you could embed a dynamic, role-specific interface directly into your app-based conversations? That’s exactly what Microsoft is now offering with the Power Apps App Agents Public Preview. In this post, we’ll walk through how to leverage the new Agent UI Framework API, Custom Tool Registry, and Agent Conversation Context API to build smarter, faster conversational apps with minimal code.

The Problem: Stuck with Generic UI and Slow Workflows

Traditional Power Virtual Agents and Power Automate workflows often force you into a one-size-fits-all UI. You can’t embed a product catalog for sales teams or a compliance checklist for HR without writing custom code. And when you need to sync data between apps, it’s a manual mess. The result? Delays, workarounds, and frustrated users.

The Solution: App Agents with Rich UI and Custom Tools

Microsoft’s new Power Apps App Agents preview solves these problems by introducing three game-changing features:

  1. Agent UI Framework API – Embed dynamic, Fluent V2-compliant interfaces directly into conversational flows.
  2. Custom Tool Registry – Package and reuse domain-specific tools like CRM lookups or analytics widgets.
  3. Agent Conversation Context API – Enable real-time data sync between Power Automate, Power Virtual Agents, and Power Apps.

Let’s dive into each one with concrete examples.

1. Building Role-Specific UI with the Agent UI Framework API

Imagine a sales rep needing to quickly look up product details during a customer call. With the Agent UI Framework API, you can embed a dynamic product catalog directly into the chat interface, eliminating the need to switch apps.

How It Works

  • Use Fluent V2 design principles to create responsive, role-specific UI components (e.g., dropdowns, tables, sliders).
  • Embed these components into Power Virtual Agents conversations using the AgentUI control.
  • Example: AgentUI.ShowProductCatalog({filter: 'Electronics'}) dynamically displays a filtered catalog.

Practical Use Case

A customer service agent can now view a customer’s support history in a sidebar widget while resolving a ticket, all within the same conversation. No more tab-switching or manual data entry.

2. Reusing Tools with the Custom Tool Registry

Legacy systems and domain-specific tools often require custom code to integrate. The Custom Tool Registry changes that by letting you package tools as reusable components.

Key Features

  • Tool Packaging: Create .tool files containing logic, metadata, and dependencies (e.g., a tool for fetching CRM data).
  • Tool Deployment: Upload tools to a central registry and reference them in Power Apps App Agents.
  • Tool Reuse: Use the same tool across multiple apps without rewriting code.

Example: Integrating with On-Premise ERP Systems

  1. Create a .tool file for an on-premise ERP lookup using Power Automate connectors.
  2. Deploy it to the registry.
  3. In your app agent, call the tool via CustomTool.Execute('ERP-Lookup', {itemID: '12345'}).

This reduces integration time by 40-60% compared to traditional methods, according to Microsoft’s internal benchmarks.

3. Real-Time Sync with the Agent Conversation Context API

The Agent Conversation Context API enables bidirectional data flow between Power Apps, Power Automate, and Power Virtual Agents. This is a big deal—for the first time, you can update a Power App form based on user input in a chatbot, and vice versa.

Use Case: HR Onboarding Workflow

  1. A new employee starts the onboarding flow in Power Virtual Agents.
  2. The chatbot asks for the employee’s department, which updates a Power App form in real time.
  3. The form then triggers a Power Automate flow to send a welcome email with the employee’s details.

This level of orchestration was previously impossible without custom middleware.

Business Impact: Faster Time-to-Market and Higher ROI

Microsoft claims the preview reduces development time for conversational apps by 40-60%. Here’s why:

  • Prebuilt UI Templates: Reduce the need for custom frontend code.
  • AI-Driven Tool Suggestions: The preview includes an AI engine that recommends tools based on conversation history (e.g., suggesting a CRM lookup when a customer’s name is mentioned).
  • Legacy System Integration: The Custom Tool Registry makes it easier to connect to on-premise ERP systems, reducing manual workarounds.

For HR teams, this means deploying a new onboarding app in days, not weeks. For sales teams, it means embedding product catalogs and pricing tools directly into customer conversations.

Future Implications: AI Co-Pilots and Multi-Modal Interfaces

The preview is just the beginning. Microsoft’s roadmap hints at:

  • Generative UI Components: AI-generated interfaces tailored to user roles.
  • Automated Tool Recommendations: AI that suggests tools based on conversation context.
  • Multi-Modal Interactions: Combining chat with embedded Power BI visuals or file attachments.

Long-term, this could transform the Power Platform into a full-stack agentic development environment, with AI co-pilots helping makers build apps without writing code.

Who Needs to Act Now?

Admins: Govern Custom Tool Deployments

Admins must now manage access to the Custom Tool Registry and monitor API usage. Set up governance policies to ensure only approved tools are deployed.

Makers: Leverage New UI/UX Capabilities

Makers can now build apps with richer interfaces without deep frontend expertise. Start experimenting with the Agent UI Framework API to create dynamic UI components.

ISVs: Build Vertical-Specific App Agent Templates

ISVs can now create industry-specific app agent templates (e.g., healthcare, retail) using the Custom Tool Registry. This opens up new revenue streams for solution providers.

IT Leaders: Evaluate Security Implications

The Custom Tool Registry allows third-party tools to be embedded. IT leaders should assess security risks and ensure tools meet compliance standards before deployment.

Getting Started: A Step-by-Step Walkthrough

Step 1: Enable the Power Apps App Agents Preview

  1. Go to the Power Platform Admin Center.
  2. Search for ‘App Agents Preview’ and enable it for your environment.
  3. Wait for the feature to activate (may take 1-2 hours).

Step 2: Create Your First Agent UI Component

  1. Open Power Apps and create a new canvas app.
  2. Use the AgentUI control to embed a Fluent V2-compliant component (e.g., a dropdown for selecting a product category).
  3. Save the app and publish it to the Power Apps portal.

Step 3: Package a Custom Tool

  1. Create a Power Automate flow that connects to your ERP system.
  2. In the Power Automate portal, select ‘Export as Tool’ from the flow’s context menu.
  3. Upload the .tool file to the Custom Tool Registry.

Step 4: Use the Tool in an App Agent

  1. Open your Power Virtual Agents bot in the Power Apps portal.
  2. In the ‘Tools’ section, select the ERP lookup tool from the registry.
  3. Use the tool in a conversation flow with CustomTool.Execute('ERP-Lookup', {itemID: '12345'}).

Summary: A Game-Changer for Conversational Apps

The Power Apps App Agents preview is a major leap forward for makers building conversational apps. With the Agent UI Framework API, Custom Tool Registry, and Agent Conversation Context API, you can now create apps with rich UI, reuse tools across environments, and sync data in real time. This isn’t just about saving time—it’s about creating experiences that feel native and intuitive to users.

Next Steps

  • Experiment with the Agent UI Framework API to build dynamic interfaces.
  • Start packaging tools for the Custom Tool Registry to streamline integrations.
  • Monitor Microsoft’s roadmap for AI-driven tool recommendations and generative UI components.

By embracing these new capabilities, makers can future-proof their apps and deliver experiences that outperform traditional chatbots and workflows.