One of the Build 2026 announcements I wanted to test immediately was the Serverless Agents Runtime for Azure Functions.
It is a public preview. So you can test it today.
Made two posts on the announcements at Build 2026 in the past: This & this
What is Serverless Agent Runtime in Azure Functions?
Microsoft has added a way to build AI agents directly inside Azure Functions, so I jumped into the official chat agent sample to see what the developer experience actually looks like.
At its core, the Serverless Agents Runtime lets you build AI agents without managing infrastructure, orchestration services, or dedicated agent hosts.
The agent runs inside your Azure Function.
It can receive input, decide what tools to call, process results, maintain context, and generate responses, all while staying within the Azure Functions model developers already know.
The shift worth noticing
It is declarative. You define the agent’s tools, instructions, and behavior — and the runtime figures out the execution in .md files. You are not writing the loop that decides when to call a tool, check the result, and call the model again. You describe what the agent can do, and the runtime handles the reasoning cycle.
What I built
I followed the chat agent sample from Microsoft Learn.
The flow is simple:
An HTTP-triggered Function receives a message.
The agent processes the request.
It calls tools when needed.
A response is returned.
Durable Task keeps track of conversation state across interactions.
Why this matters
For teams already using Azure Functions, this lowers the barrier to building AI-powered applications. You can add agent capabilities to an architecture you already understand.
You don’t need a separate agent platform.
You don’t need to host another service.
You don’t need to learn a completely different runtime.
The bigger picture
This becomes even more interesting when combined with the new Managed Connectors announcement, which I talked about here
An agent could monitor incoming emails, understand the content, trigger actions, update business systems, and post results into Teams, all from the same Function App.
I’ll be exploring more of the Build 2026 announcements over the coming weeks.
That’s all for today, see you in the next one.
