Orchestrate Copilot Studio Agents With the A2A Bridge

Introducing the A2A Bridge for Microsoft Copilot Studio

Overview

Many enterprises already run agents in Copilot Studio, but those agents can’t join A2A-based multi-agent workflows without custom adapters. Today, the A2A Bridge for Microsoft Copilot Studio is generally available in Agent Fabric, following the release of the A2A Bridge for Agentforce in September.

The bridge puts an Agent2Agent (A2A) protocol endpoint in front of a Copilot Studio agent. It runs on Omni Gateway, so A2A clients, including the Agent Broker, can discover, call, and govern the agent, leaving the agent itself unchanged.

Why It Matters

Copilot Studio agents talk through Direct Line, an activity-based chat API. A2A clients expect tasks with states. Without a bridge, connecting each to an orchestrator means building and maintaining a custom adapter.

The bridge gives you:

• Your existing agents, put to work: Copilot Studio agents join multi-agent A2A flows with no rewrites.
• One set of policies: The inbound authentication and A2A policies you use for other agents apply to bridged agents too.
• Configuration, not code: A guided wizard publishes the agent card and deploys the bridge together.
• A path to native A2A: If Copilot Studio’s native A2A support fits your needs later, retire the bridge and point your clients at the native endpoint.

Microsoft is also adding native A2A to Copilot Studio, which requires callers to authenticate as a signed-in user. The bridge is available today and supports services such as Agent Broker, which call the agent under their own identity. Use the bridge for service-to-service orchestration today, and native A2A when callers need to act as a signed-in user.

How It Works

The bridge is a chain of policies on Omni Gateway: inbound authentication, any A2A policies, then the bridge policy. To an A2A client, it looks like any other A2A server.

Figure 1. An A2A client calls the bridge on Omni Gateway. The bridge translates the call to Direct Line, polls for the reply, and returns an A2A task.

• The client reads the agent card from the instance’s discovery URL.
• The gateway checks the caller and applies A2A policies.
• The bridge turns the A2A message into a Direct Line activity. Calls that share a context ID reuse the same Direct Line conversation.
• The bridge polls Direct Line until the turn completes or a configurable timeout elapses. A classifier then decides whether the reply is final or asks for more input.
• The client receives an A2A task with an ID and a state. If the agent hasn’t answered before the timeout, the task is returned in the submitted state, and the client calls GetTask later to get the result.

Key Features

• One wizard: Pick the agent in Agent Registry, edit its card, and deploy the first instance in one flow.
• An accurate agent card: Edit, hide, or add skills. The platform locks capabilities the bridge can’t support.
• Multi-turn, long-running, and attachments: Conversations carry across calls. Slow turns come back as submitted tasks you can poll. Files can be sent as a URI reference or inline Base64 content.
• Authentication on both sides: Callers authenticate with JWT validation, Client ID Enforcement, or Basic Authentication. The bridge authenticates to Copilot Studio with a Direct Line secret.

Get Started

You need an Anypoint Platform account with Exchange and API Manager permissions, a managed or self-managed Omni Gateway, and a Copilot Studio agent registered in Agent Registry, for example through Scanners. Have the agent’s Direct Line secret and endpoint URL ready.

Open the agent in Agent Registry and select Configure A2A Bridge & Deploy First Instance. The wizard covers the card, the gateway instance, and both authentication settings. The full steps are in Make an Agent A2A-Compliant.

What to Know

• Scope: Copilot Studio agents only. Microsoft 365 Copilot agents aren’t supported.
• Identity: Copilot Studio sees the bridge, not the original caller, so enforce caller authorization at the gateway. Agents whose topics or actions require the end user to sign in won’t work through the bridge.
• Task state is inferred: Direct Line has no task states, so the bridge infers completed and input-required on a best-effort basis.
• No streaming, cancellation, or push notifications: The bridge polls Direct Line and returns complete replies.
• State lives in gateway memory: An Omni Gateway restart loses task state, and conversations expire on the Copilot Studio side.

Demo

What’s Next

The bridge is designed so you’re never locked in. When Copilot Studio’s native A2A fits your scenario, point your A2A clients at the native endpoint and retire the bridge. Start with one agent and check the task states and the timeout against your workload. For full setup steps, see .