story: DGR-041 Register native Shard capabilities without redesigning Meshnet

packages/node/meshnet_node/capability.py

@@ -322,6 +322,49 @@ class BackendIdentity:
         )
 
 
+@dataclass(frozen=True)
+class ExecutionCapacity:
+    """Backend-neutral limits reserved for one registered capability.
+
+    The optional shape preserves existing Transformers reports unchanged while
+    allowing a native Shard to state its measured/admitted resource envelope.
+    """
+
+    memory_capacity_bytes: int | None = None
+    kv_capacity_tokens: int | None = None
+    max_concurrent_sessions: int | None = None
+
+    def __post_init__(self) -> None:
+        for name in (
+            "memory_capacity_bytes",
+            "kv_capacity_tokens",
+            "max_concurrent_sessions",
+        ):
+            value = getattr(self, name)
+            if value is not None:
+                _require_int(value, f"capacity.{name}", 1)
+
+    def to_dict(self) -> dict:
+        return {
+            "memory_capacity_bytes": self.memory_capacity_bytes,
+            "kv_capacity_tokens": self.kv_capacity_tokens,
+            "max_concurrent_sessions": self.max_concurrent_sessions,
+        }
+
+    @classmethod
+    def from_dict(cls, data: Any) -> ExecutionCapacity:
+        doc = _as_mapping(data, "capacity")
+        values: dict[str, int | None] = {}
+        for name in (
+            "memory_capacity_bytes",
+            "kv_capacity_tokens",
+            "max_concurrent_sessions",
+        ):
+            value = doc.get(name)
+            values[name] = None if value is None else _require_int(value, f"capacity.{name}", 1)
+        return cls(**values)
+
+
 def _as_mapping(data: Any, field_name: str) -> Mapping[str, Any]:
     if not isinstance(data, Mapping):
         raise CapabilityReportError(
@@ -353,6 +396,7 @@ class CapabilityReport:
     diagnostics: tuple[str, ...] = ()
     schema_version: int = CAPABILITY_SCHEMA_VERSION
     identity: ShardIdentity | None = None
+    capacity: ExecutionCapacity | None = None
 
     def __post_init__(self) -> None:
         if self.status not in VALID_STATUSES:
@@ -410,6 +454,8 @@ class CapabilityReport:
         }
         if self.identity is not None:
             doc["identity"] = self.identity.to_dict()
+        if self.capacity is not None:
+            doc["capacity"] = self.capacity.to_dict()
         return doc
 
     def to_json(self, indent: int | None = None) -> str:
@@ -451,6 +497,9 @@ class CapabilityReport:
             identity=(
                 None if raw_identity is None else ShardIdentity.from_dict(raw_identity)
             ),
+            capacity=(
+                None if doc.get("capacity") is None else ExecutionCapacity.from_dict(doc["capacity"])
+            ),
         )
 
     @classmethod
@@ -486,6 +535,7 @@ def build_capability_report(
     validated_at: float | None = None,
     environ: Mapping[str, str] | None = None,
     identity: ShardIdentity | None = None,
+    capacity: ExecutionCapacity | None = None,
 ) -> CapabilityReport:
     """Assemble a report from flat validation results.
 
@@ -518,4 +568,5 @@ def build_capability_report(
         duration_ms=duration_ms,
         diagnostics=sanitize_diagnostics(diagnostics, environ),
         identity=identity,
+        capacity=capacity,
     )