Connected data rules can check whole application paths
Theo describes the T3 stack's composition, where Prisma produces typed functions and tRPC carries those types toward the interface. Type safety then reaches from an interface hook or component back to the database underneath it. He compares that satisfying connection with agent setups, saying he now experiences similar moments much more often.
Reuse data definitions instead of copying them
When a layer produces types, have the next layer consume them instead of declaring the same shapes again. Look for equivalent connections in the agent setup so tools and checks share the same source. Let schemas, tools, tests, and documentation derive from that source where the existing contract supports the connection.
Connect duplicated data definitions when they drift apart
This fits a stack where handwritten copies of the same underlying shape have begun to drift apart. The composition opportunity is to carry the existing guarantee across a boundary instead of recreating it there. Without duplicated contracts to connect, this tip does not supply a reason to adopt Theo's particular stack.
You need not adopt Theo's chosen technologies
The named technologies belong to Theo's example, and the video does not make them a general requirement. His report of experiencing these moments almost daily is anecdotal rather than a measured engineering outcome. The idea still applies where a single typed source can connect layers that currently repeat its contract.