D104 - Blocked instructions name their dependency

Status: decided Date: 2026-08-20

model::BLOCKED lists instructions whose semantics are understood but which wait on a missing subsystem, each with its reason. It is not a to-do list: anything that could simply be written is written.

Why: the worklist must tell an instruction nobody has looked at from one waiting on a whole subsystem, because they rank differently.

Rejected:

• Mapping an export onto the observation buffer: an invented destination that appears to work.
• Leaving blocked instructions unlabelled: an afternoon and a subsystem look alike.