Advanced Agents From First Principles 05: Is One Model Doing Everything? Build a Mixture of Experts at the Agent Level

Sat, 08 Aug 2026 23:41:00 +0100

A common agent architecture starts simply:

request
   ↓
model
   ↓
action

That simplicity is valuable.

It should be your default.

But eventually you may notice something strange.

The same model is being asked to do everything:

classify the task,
search documentation,
reason about code,
write SQL,
review a patch,
summarize logs,
judge another model,
decide whether a deployment is safe,
and answer simple questions that did not require an expensive model in the first place.

At that point the problem may no longer be:

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