Start rail/rapp/reef fabric adaptation

docs/declaration-schema.md

@@ -87,6 +87,13 @@ Optional relationship fields:
 
 Schema: `schemas/service.schema.yaml`
 
+Recommended compatibility-first `spec.service_type` values for the new
+Railiance repo families are:
+
+- `execution-rail`
+- `managed-workload-package`
+- `substrate-boundary`
+
 ### CapabilityDeclaration
 
 A stable semantic ability that consumers depend on.
@@ -163,6 +170,22 @@ Schema: `schemas/dependency.schema.yaml`
 type catalogs. Unknown types are allowed by the document schema but should fail
 graph validation.
 
+## Repository-Family Starter Guidance
+
+Until stronger repo-family metadata exists in registry and export projections,
+future repo-local declarations should start with these minimal shapes:
+
+- `rail-*`: one `ServiceDeclaration` using `spec.service_type:
+  execution-rail`, plus one `CapabilityDeclaration` using
+  `spec.capability_type: workload-execution-contract`
+- `rapp-*`: one `ServiceDeclaration` using `spec.service_type:
+  managed-workload-package`
+- `reef-*`: one `ServiceDeclaration` using `spec.service_type:
+  substrate-boundary`
+
+This is a compatibility-first convention, not a claim that the full repo-family
+graph model is complete.
+
 ### BindingAssertion
 
 A source-controlled assertion that resolves a dependency to a provider