ADK domains

The ADK repository reserves three domain directories alongside the shipped assembly rules, each carrying a README stating that no rules are shipped yet, so that when rules land they attach at an already-agreed place rather than forcing a reorganisation.

The shipped assembly rules are geometric: they check placement and attachment density. The three reserved domains below are further axes along which an assembly can fail for reasons geometry alone cannot express. They are not the only ones: the inter-die connectivity axis is in the kit’s scope rather than in a reserved domain, and it is not part of this preview release. See Roadmap.

Thermal

Reserved. Directory thermal/ in the ADK repository.

Intended scope: interposer hot-spot and power-density checks against chiplet thermal maps. An assembly that is geometrically legal can still be thermally unviable, because dissipation from one die raises the junction temperature of its neighbour through the shared substrate. Checking that requires a per-chiplet thermal description that the current data model does not carry.

Power delivery

Reserved. Directory power/ in the ADK repository.

Intended scope: interposer power delivery network coverage checks against chiplet supply maps. The question is whether the substrate delivers adequate current to every die’s supply pads within an acceptable voltage drop, which again needs a per-chiplet description the assembly file does not model today.

Timing

Reserved. Directory timing/ in the ADK repository.

Intended scope: inter-chiplet trace-length budgets on the interposer. Static timing analysis across die boundaries is a broader open problem and is not in scope for a rule deck.

What would have to change first

All three domains share one prerequisite, which is why they are reserved rather than in progress: each needs per-chiplet characterisation data that the assembly does not carry, a thermal map, a supply map, a timing model. The .chiplet format deliberately scopes itself to physical assembly and points at part-description standards for this kind of data. See The .chiplet assembly file for how that boundary is drawn.

Until that data has an agreed home, an ADK rule in these domains would have nothing to check against.