diff --git a/mltrail_verifiable_provenance_ledger_for/registry.py b/mltrail_verifiable_provenance_ledger_for/registry.py
index a45c4dd..b43f70e 100644
--- a/mltrail_verifiable_provenance_ledger_for/registry.py
+++ b/mltrail_verifiable_provenance_ledger_for/registry.py
@@ -1,5 +1,19 @@
 from typing import Dict, Any
 
+
+# Lightweight default schemas for core MLTrail contracts. This enables a
+# canonical, language-agnostic registry that adapters can reference for
+# conformance checks and schema validation in MVP deployments.
+_DEFAULT_CONTRACT_SCHEMAS: Dict[str, Dict[str, Any]] = {
+    "Experiment": {"fields": ["id", "name", "version", "description", "metadata"]},
+    "Run": {"fields": ["id", "experiment_id", "parameters", "metrics", "environment_hash"]},
+    "Dataset": {"fields": ["id", "name", "version", "metadata"]},
+    "Model": {"fields": ["id", "architecture", "fingerprint", "metadata"]},
+    "Environment": {"fields": ["id", "language", "version", "dependencies", "container_hash"]},
+    "EvaluationMetric": {"fields": ["name", "value", "unit"]},
+    "Policy": {"fields": ["id", "rules", "metadata"]},
+}
+
 class ContractRegistry:
     def __init__(self) -> None:
         self._contracts: Dict[str, Dict[str, Any]] = {}
@@ -12,3 +26,13 @@ class ContractRegistry:
 
     def all_contracts(self) -> Dict[str, Any]:
         return self._contracts
+
+    def register_default_contracts(self) -> None:
+        """Register a canonical set of core MLTrail contract schemas.
+
+        This helps adapters and tooling validate payloads against expected
+        fields, enabling consistent interoperability across languages.
+        """
+        for name, schema in _DEFAULT_CONTRACT_SCHEMAS.items():
+            # Use a stable default version for defaults; allow user overrides if needed
+            self.register_contract(name, schema, version="1.0.0")
diff --git a/tests/test_registry_defaults.py b/tests/test_registry_defaults.py
new file mode 100644
index 0000000..4a0e74f
--- /dev/null
+++ b/tests/test_registry_defaults.py
@@ -0,0 +1,14 @@
+from mltrail_verifiable_provenance_ledger_for.registry import ContractRegistry, _DEFAULT_CONTRACT_SCHEMAS
+
+
+def test_default_contracts_registered():
+    reg = ContractRegistry()
+    reg.register_default_contracts()
+
+    # Ensure all canonical contracts are registered with their expected fields
+    for name, expected in _DEFAULT_CONTRACT_SCHEMAS.items():
+        contract = reg.get_contract(name)
+        assert contract is not None, f"Contract {name} not registered"
+        assert contract.get("schema") is not None, f"Schema for {name} missing"
+        fields = contract["schema"].get("fields")
+        assert fields == expected["fields"], f"Fields for {name} do not match expected"