Microsoft Foundry Agent Service and Copilot Studio
Overview
Foundry Agent Service offers Prompt Agents (configuration only), voice prompt agents, and Hosted Agents, where you bring your own code built with Microsoft Agent Framework, LangGraph, the OpenAI SDK, the Anthropic SDK, the GitHub Copilot SDK or custom code. Agents publish through OpenResponses, the Activity Protocol, the Invocations Protocol and A2A, with versioned publishing to Teams and Microsoft 365 Copilot.
Copilot Studio multi-agent
Copilot Studio supports child agents, connected Copilot Studio agents, and external agents over A2A, with Foundry agents, Fabric data agents and Microsoft 365 Agents SDK agents in preview. Microsoft documents limits: an agent used as a main agent cannot also be a connected agent elsewhere, citations may not persist between agents, and orchestration hops add latency. Microsoft suggests splitting into connected agents when a main agent has 30 to 40 or more action choices.
Interoperability
A2A v1.0 is GA in Foundry. MCP support includes remote MCP servers, Toolboxes as a single managed MCP-compatible endpoint, and custom MCP servers on Azure Functions.
Governance
Microsoft Entra Agent ID gives each agent an identity. Also OAuth on-behalf-of passthrough, Azure RBAC, content filters including cross-prompt injection filtering, end-to-end tracing, Application Insights and evaluations.
Pricing
Foundry agent pricing is usage-based (model and tool consumption); Microsoft's agent pricing page could not be retrieved, so we do not quote rates. Microsoft 365 Copilot is $30 per user per month, paid yearly. Copilot Studio uses Copilot Credits, prepaid (Microsoft cites up to 20% savings) or pay-as-you-go.
Strengths
- A2A v1.0 GA and broad MCP support.
- Per-agent identity with Entra Agent ID.
- Direct publishing to Teams and Microsoft 365 Copilot.
- Hosted Agents accept code from several frameworks.
Limitations
- Runtime, identity and governance live in Azure; no other-cloud or self-hosted runtime is stated.
- Documented multi-agent limits in Copilot Studio.
- Agent pricing is hard to model from public pages.
How it fits with BAND
Foundry and Copilot Studio are where Microsoft-side agents live. BAND lists Azure AI Foundry and Copilot Studio integrations, so those agents can collaborate with agents from AWS, Salesforce, SAP or internal frameworks in BAND rooms while Foundry keeps hosting and identity.
Sources
- learn.microsoft.com/en-us/azure/ai-foundry/agents/overview
- learn.microsoft.com/en-us/microsoft-copilot-studio/authoring-add-other-agents
- microsoft.com/en-us/microsoft-365-copilot/pricing/copilot-studio
Reviewed Sep 2026
Frequently asked questions
Does Microsoft Foundry support A2A?
Yes. A2A v1.0 is generally available in Foundry Agent Service; v0.3 remains in preview.
Can Copilot Studio agents work with agents from other vendors?
Copilot Studio can call external agents over A2A. For many-to-many collaboration across vendors with people involved, a collaboration layer such as BAND, which lists Copilot Studio as an integration, adds shared rooms and delivery tracking.
Compare with
Connect Microsoft Foundry agents with agents from other vendors