Your Agent's Planner Shouldn't Be a Language Model
· 21 min read

Here is a question worth sitting with. Your agent has twelve steps it can take, MCP tool calls among them. A user asks for something that needs four of them, in a particular order. Who decides that order?
For almost every agent shipping today, the answer is: the language model. The same stochastic, temperature-sampled, occasionally-confidently-wrong component that we carefully sandbox, rate-limit, and never trust with raw SQL is also the component we hand the entire execution plan to. We validate its outputs obsessively. We rarely validate its plans, because the plan does not exist as an object you could validate.
There is another way to do this, it comes from video games, and it has a production release on the JVM.