diff --git a/proto-docs/netmap.md b/proto-docs/netmap.md
index a983bbd..0a75dc4 100644
--- a/proto-docs/netmap.md
+++ b/proto-docs/netmap.md
@@ -231,6 +231,17 @@ Administrator-defined Attributes of the NeoFS Storage Node.
 `Attribute` is a Key-Value metadata pair. Key name must be a valid UTF-8
 string. Value can't be empty.
 
+Attributes can be constructed into a chain of attributes: any attribute can
+have a parent attribute and a child attribute (except the first and the last
+one). A string representation of the chain of attributes in NeoFS Storage
+Node configuration uses ":" and "/" symbols, e.g.:
+
+       `NEOFS_NODE_ATTRIBUTE_1=key1:val1/key2:val2`
+
+Therefore the string attribute representation in the Node configuration must
+use "\:", "\/" and "\\" escaped symbols if any of them appears in an attribute's
+key or value.
+
 Node's attributes are mostly used during Storage Policy evaluation to
 calculate object's placement and find a set of nodes satisfying policy
 requirements. There are some "well-known" node attributes common to all the