diff --git a/proto/api b/proto/api
index f6a14e5a..510c7f37 160000
--- a/proto/api
+++ b/proto/api
@@ -1 +1 @@
-Subproject commit f6a14e5ad41fcbc0ea1117348daea90ba2c8c3c3
+Subproject commit 510c7f37c67d9a0d50198f0378ac2951adf13e2e
diff --git a/sdk/v1/workflow_metadata.pb.go b/sdk/v1/workflow_metadata.pb.go
index b444e4fe..3cf11144 100644
--- a/sdk/v1/workflow_metadata.pb.go
+++ b/sdk/v1/workflow_metadata.pb.go
@@ -110,9 +110,12 @@ type WorkflowDefinition struct {
 
 	// A name scoped by the task queue that maps to this workflow definition.
 	// If missing, this workflow is a dynamic workflow.
-	Type              string                           `protobuf:"bytes,1,opt,name=type,proto3" json:"type,omitempty"`
-	QueryDefinitions  []*WorkflowInteractionDefinition `protobuf:"bytes,2,rep,name=query_definitions,json=queryDefinitions,proto3" json:"query_definitions,omitempty"`
+	Type string `protobuf:"bytes,1,opt,name=type,proto3" json:"type,omitempty"`
+	// Query definitions, sorted by name.
+	QueryDefinitions []*WorkflowInteractionDefinition `protobuf:"bytes,2,rep,name=query_definitions,json=queryDefinitions,proto3" json:"query_definitions,omitempty"`
+	// Signal definitions, sorted by name.
 	SignalDefinitions []*WorkflowInteractionDefinition `protobuf:"bytes,3,rep,name=signal_definitions,json=signalDefinitions,proto3" json:"signal_definitions,omitempty"`
+	// Update definitions, sorted by name.
 	UpdateDefinitions []*WorkflowInteractionDefinition `protobuf:"bytes,4,rep,name=update_definitions,json=updateDefinitions,proto3" json:"update_definitions,omitempty"`
 }