Microsoft Build 2026

Keep the Agent as Ordinary Code: Packaging Without the Rewrite

原演讲者: Facundo, Principal Product Manager · Microsoft / Anacuma, Senior Software Engineer · Microsoft

来源已核验演讲日期待核实presentation16:26EN2 分钟阅读

An agent loop kept as ordinary inspectable code stays debuggable with ordinary tools, whereas a loop absorbed into a runtime is debuggable only through what that runtime chooses to expose — which is exactly what you need when something goes wrong.

The question this session opens with is narrower than most Build sessions and more useful for it: you have built an agent with open-source tooling, so how does it reach production without being rewritten?

The answer they demonstrate is worth extracting from the product context, because the design principle underneath it applies regardless of platform.

Keeping the agent as ordinary code

The property they emphasise is that the tool boundary stays inspectable and the agent remains normal code (4:02).

This sounds unremarkable and is not. A great deal of agent framework design pulls the loop inside a runtime you configure rather than write — you declare tools, describe behaviour, and the framework decides what happens between steps. It works until something goes wrong, at which point the thing you need to inspect is exactly the part you did not write.

Their framing of the loop is deliberately plain: it asks the model for the next step, runs tools when needed, and uses each result to decide what follows (1:08). Kept as code, that loop is debuggable with ordinary tools. Wrapped in a runtime, it is debuggable only through whatever the runtime chooses to expose.

The token argument for local tools

The technical observation most likely to transfer concerns where tool definitions live.

Connecting to a remote tool server means retrieving its instructions — often large structured definitions — into context before anything is called. Defining the tool in the agent's own code avoids that round trip and the context it consumes (8:34).

The trade-off is real and worth stating in both directions. Remote tool servers give you a shared, versioned, independently maintained definition that many agents can use, which is exactly what you want across an organisation. Local definitions are cheaper per invocation and cost you that sharing.

Which means the correct answer is architectural rather than universal: tools used by one agent belong close to it, and tools used by many belong behind a shared interface. The failure mode is treating either as the default and paying the other's costs everywhere.

What packaging is actually solving

The problem statement — reaching production without a rewrite — is the honest description of where most agent projects lose time.

A prototype built with open-source tooling runs on a developer's machine with their credentials, their environment and their patience for restarting it. Production requires identity, isolation, observability, deployment and a way to update it, none of which the prototype needed. The usual outcome is that the prototype is treated as a specification and rebuilt on whatever the platform supports.

What is being offered here is that the packaging changes and the agent does not. Whether that holds in practice is the question a sixteen-minute session cannot answer. But it is the right thing to be attempting, and it is a more useful target than another orchestration abstraction.

演讲章节

关键要点

  1. 01

    The design property they emphasise is that the tool boundary stays inspectable and the agent remains ordinary code rather than runtime configuration. 4:02

  2. 02

    Their description of the loop is deliberately plain: ask the model for the next step, run tools when needed, use each result to decide what follows. 1:08

  3. 03

    Remote tool servers cost context before anything is called, since their instructions must be retrieved; local definitions avoid that and give up sharing. 8:34

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