Frame
The substrate the supply is built on.
Frame is the DAAC-native application framework: the substrate that apps run on. It shares most of its DNA with DAF, the framework a decade of live deployments runs on; what sets it apart is that it is agent-oriented, built for apps to be composed and realigned by agents in Forge rather than by hand. It extends DAF for the agent era, it does not replace it.
What makes Frame load-bearing for DAAC is that compatibility is not a feature you add. Every app built on Frame implements the shared conventions (identity, schema, provenance, sharing rules) from the inside. The data it captures is exchangeable across the ecosystem from the moment it exists, with no later integration step.
Apps are built on Frame by humans writing configuration directly, or by agents in Forge. Frame is the substrate; it does not build apps itself.
Where it sits. Stands on the shared conventions at within-app scope. Forge builds on Frame; the data Frame apps capture is the supply.