diff --git a/CHANGELOG.md b/CHANGELOG.md
index 3bf2e5899..1ffd543dc 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -3,6 +3,8 @@
 Note: For changes to the API, see https://shopify.dev/changelog?filter=api
 ## Unreleased
 
+- [#1272](https://github.com/Shopify/shopify-api-ruby/issues/1272) and [#1273](https://github.com/Shopify/shopify-api-ruby/issues/1273) Raise `NoMethodError` for unknown REST property getters and report dynamic properties consistently from `respond_to?`.
+
 ## 16.4.0 (2026-11-05)
 - [#1481](https://github.com/Shopify/shopify-api-ruby/pull/1481) `ShopifyAPI::Auth::TokenExchange.exchange_token` now raises `ShopifyAPI::Errors::InvalidJwtTokenError` when token exchange rejects the session token with `invalid_identity_session`, matching the existing `invalid_subject_token` handling.
 - [#1475](https://github.com/Shopify/shopify-api-ruby/pull/1475) Add an optional `client_assertion:` argument to `ShopifyAPI::Auth::ClientCredentials.client_credentials`. When supplied, the token request authenticates with a JWT client assertion and sends no client secret. Omitting it, or passing `nil`, keeps the existing client-secret behavior. See the [OAuth documentation](docs/usage/oauth.md#client-assertion-authentication).
diff --git a/lib/shopify_api/rest/base.rb b/lib/shopify_api/rest/base.rb
index 3cc4ebd18..ae5b084bf 100644
--- a/lib/shopify_api/rest/base.rb
+++ b/lib/shopify_api/rest/base.rb
@@ -11,6 +11,12 @@ class Base
       extend T::Helpers
       abstract!
 
+      INTERNAL_PROPERTIES = T.let(
+        ["session", "client", "custom_prefix", "forced_nils", "aliased_properties"].freeze,
+        T::Array[String],
+      )
+      private_constant :INTERNAL_PROPERTIES
+
       @headers = T.let(nil, T.nilable(T::Hash[T.any(Symbol, String), String]))
       @has_one = T.let({}, T::Hash[Symbol, T::Class[T.anything]])
       @has_many = T.let({}, T::Hash[Symbol, T::Class[T.anything]])
@@ -185,7 +191,7 @@ def get_path(http_method:, operation:, entity: nil, ids: {})
 
             url_ids = ids.transform_keys(&:to_sym)
             path_ids.each do |id|
-              if url_ids[id].nil? && (entity_id = entity&.public_send(id))
+              if url_ids[id].nil? && (entity_id = entity&.send(:get_optional_property, id))
                 url_ids[id] = entity_id
               end
             end
@@ -315,16 +321,20 @@ def method_missing(meth_id, val = nil)
           set_property(var, val)
           @forced_nils[var] = val.nil?
         else
+          return super unless dynamic_property_defined?(var)
+
           get_property(var)
         end
       end
 
-      sig { params(meth_id: Symbol, args: T.untyped).void }
-      def respond_to_missing?(meth_id, *args)
+      sig { params(meth_id: Symbol, include_private: T::Boolean).returns(T::Boolean) }
+      def respond_to_missing?(meth_id, include_private = false)
         str = meth_id.id2name
         match = str.match(/([^=]+)=/)
 
-        match.nil? ? true : super
+        return true unless match.nil?
+
+        dynamic_property_defined?(str) || super(meth_id, include_private)
       end
 
       sig { params(saving: T::Boolean).returns(T::Hash[String, T.untyped]) }
@@ -430,14 +440,14 @@ def attributes_to_update
       def build_required_attributes(http_method:)
         required_attributes = {}
 
-        primary_key_value = send(self.class.primary_key)
+        primary_key_value = get_optional_property(self.class.primary_key, include_private: true)
         unless primary_key_value.nil?
           required_attributes[self.class.primary_key] = primary_key_value
         end
 
         path_ids = deduce_path_ids(http_method)
         path_ids&.each do |path_id|
-          path_id_value = send(path_id)
+          path_id_value = get_optional_property(path_id, include_private: true)
           required_attributes[path_id.to_s] = path_id_value unless path_id_value.nil?
         end
 
@@ -446,7 +456,7 @@ def build_required_attributes(http_method:)
 
       sig { returns(Symbol) }
       def deduce_write_verb
-        send(self.class.primary_key) ? :put : :post
+        get_optional_property(self.class.primary_key, include_private: true) ? :put : :post
       end
 
       sig { params(method: Symbol).returns(T.nilable(String)) }
@@ -488,12 +498,19 @@ def set_property(key, val)
         # variables. To work around that, we're cleaning them up here but keeping track of the properties that were
         # aliased this way. When loading up the property, we can map back from the "invalid" field so that it is
         # transparent to outside callers
-        clean_key = key.to_s.gsub(/[\?\s]/, "")
+        clean_key = key.to_s.gsub(/[?\s]/, "")
         @aliased_properties[key.to_s] = clean_key if clean_key != key
 
         instance_variable_set("@#{clean_key}", val)
       end
 
+      sig { params(key: T.any(String, Symbol), include_private: T::Boolean).returns(T.untyped) }
+      def get_optional_property(key, include_private: false)
+        return nil unless respond_to?(key, include_private)
+
+        include_private ? send(key) : public_send(key)
+      end
+
       sig { params(key: T.any(String, Symbol)).returns(T.untyped) }
       def get_property(key)
         clean_key = @aliased_properties.key?(key.to_s) ? @aliased_properties[key.to_s] : key
@@ -501,6 +518,14 @@ def get_property(key)
         instance_variable_get("@#{clean_key}")
       end
 
+      sig { params(key: String).returns(T::Boolean) }
+      def dynamic_property_defined?(key)
+        property = @aliased_properties[key] || key
+        !INTERNAL_PROPERTIES.include?(property) && instance_variable_defined?("@#{property}")
+      rescue NameError
+        false
+      end
+
       sig do
         params(
           element: T.nilable(T.any(T::Hash[String, T.untyped], ShopifyAPI::Rest::Base)),
diff --git a/lib/shopify_api/rest/resources/2022_07/dispute_evidence.rb b/lib/shopify_api/rest/resources/2022_07/dispute_evidence.rb
index faf7ea5c0..7e6d4c39a 100644
--- a/lib/shopify_api/rest/resources/2022_07/dispute_evidence.rb
+++ b/lib/shopify_api/rest/resources/2022_07/dispute_evidence.rb
@@ -30,7 +30,7 @@ def initialize(session: ShopifyAPI::Context.active_session, from_hash: nil)
       @fulfillments = T.let(nil, T.nilable(T::Array[T.untyped]))
       @id = T.let(nil, T.nilable(Integer))
       @payments_dispute_id = T.let(nil, T.nilable(Integer))
-      @product_description = T.let(nil, T.nilable(T::Hash[T.untyped, T.untyped]))
+      @product_description = T.let(nil, T.nilable(String))
       @refund_policy_disclosure = T.let(nil, T.nilable(String))
       @refund_refusal_explanation = T.let(nil, T.nilable(String))
       @shipping_address = T.let(nil, T.nilable(T::Hash[T.untyped, T.untyped]))
@@ -74,7 +74,7 @@ def initialize(session: ShopifyAPI::Context.active_session, from_hash: nil)
     attr_reader :id
     sig { returns(T.nilable(Integer)) }
     attr_reader :payments_dispute_id
-    sig { returns(T.nilable(T::Hash[T.untyped, T.untyped])) }
+    sig { returns(T.nilable(String)) }
     attr_reader :product_description
     sig { returns(T.nilable(String)) }
     attr_reader :refund_policy_disclosure
diff --git a/lib/shopify_api/rest/resources/2022_10/dispute_evidence.rb b/lib/shopify_api/rest/resources/2022_10/dispute_evidence.rb
index faf7ea5c0..7e6d4c39a 100644
--- a/lib/shopify_api/rest/resources/2022_10/dispute_evidence.rb
+++ b/lib/shopify_api/rest/resources/2022_10/dispute_evidence.rb
@@ -30,7 +30,7 @@ def initialize(session: ShopifyAPI::Context.active_session, from_hash: nil)
       @fulfillments = T.let(nil, T.nilable(T::Array[T.untyped]))
       @id = T.let(nil, T.nilable(Integer))
       @payments_dispute_id = T.let(nil, T.nilable(Integer))
-      @product_description = T.let(nil, T.nilable(T::Hash[T.untyped, T.untyped]))
+      @product_description = T.let(nil, T.nilable(String))
       @refund_policy_disclosure = T.let(nil, T.nilable(String))
       @refund_refusal_explanation = T.let(nil, T.nilable(String))
       @shipping_address = T.let(nil, T.nilable(T::Hash[T.untyped, T.untyped]))
@@ -74,7 +74,7 @@ def initialize(session: ShopifyAPI::Context.active_session, from_hash: nil)
     attr_reader :id
     sig { returns(T.nilable(Integer)) }
     attr_reader :payments_dispute_id
-    sig { returns(T.nilable(T::Hash[T.untyped, T.untyped])) }
+    sig { returns(T.nilable(String)) }
     attr_reader :product_description
     sig { returns(T.nilable(String)) }
     attr_reader :refund_policy_disclosure
diff --git a/lib/shopify_api/rest/resources/2023_01/dispute_evidence.rb b/lib/shopify_api/rest/resources/2023_01/dispute_evidence.rb
index faf7ea5c0..7e6d4c39a 100644
--- a/lib/shopify_api/rest/resources/2023_01/dispute_evidence.rb
+++ b/lib/shopify_api/rest/resources/2023_01/dispute_evidence.rb
@@ -30,7 +30,7 @@ def initialize(session: ShopifyAPI::Context.active_session, from_hash: nil)
       @fulfillments = T.let(nil, T.nilable(T::Array[T.untyped]))
       @id = T.let(nil, T.nilable(Integer))
       @payments_dispute_id = T.let(nil, T.nilable(Integer))
-      @product_description = T.let(nil, T.nilable(T::Hash[T.untyped, T.untyped]))
+      @product_description = T.let(nil, T.nilable(String))
       @refund_policy_disclosure = T.let(nil, T.nilable(String))
       @refund_refusal_explanation = T.let(nil, T.nilable(String))
       @shipping_address = T.let(nil, T.nilable(T::Hash[T.untyped, T.untyped]))
@@ -74,7 +74,7 @@ def initialize(session: ShopifyAPI::Context.active_session, from_hash: nil)
     attr_reader :id
     sig { returns(T.nilable(Integer)) }
     attr_reader :payments_dispute_id
-    sig { returns(T.nilable(T::Hash[T.untyped, T.untyped])) }
+    sig { returns(T.nilable(String)) }
     attr_reader :product_description
     sig { returns(T.nilable(String)) }
     attr_reader :refund_policy_disclosure
diff --git a/lib/shopify_api/rest/resources/2023_04/dispute_evidence.rb b/lib/shopify_api/rest/resources/2023_04/dispute_evidence.rb
index faf7ea5c0..7e6d4c39a 100644
--- a/lib/shopify_api/rest/resources/2023_04/dispute_evidence.rb
+++ b/lib/shopify_api/rest/resources/2023_04/dispute_evidence.rb
@@ -30,7 +30,7 @@ def initialize(session: ShopifyAPI::Context.active_session, from_hash: nil)
       @fulfillments = T.let(nil, T.nilable(T::Array[T.untyped]))
       @id = T.let(nil, T.nilable(Integer))
       @payments_dispute_id = T.let(nil, T.nilable(Integer))
-      @product_description = T.let(nil, T.nilable(T::Hash[T.untyped, T.untyped]))
+      @product_description = T.let(nil, T.nilable(String))
       @refund_policy_disclosure = T.let(nil, T.nilable(String))
       @refund_refusal_explanation = T.let(nil, T.nilable(String))
       @shipping_address = T.let(nil, T.nilable(T::Hash[T.untyped, T.untyped]))
@@ -74,7 +74,7 @@ def initialize(session: ShopifyAPI::Context.active_session, from_hash: nil)
     attr_reader :id
     sig { returns(T.nilable(Integer)) }
     attr_reader :payments_dispute_id
-    sig { returns(T.nilable(T::Hash[T.untyped, T.untyped])) }
+    sig { returns(T.nilable(String)) }
     attr_reader :product_description
     sig { returns(T.nilable(String)) }
     attr_reader :refund_policy_disclosure
diff --git a/lib/shopify_api/rest/resources/2023_07/dispute_evidence.rb b/lib/shopify_api/rest/resources/2023_07/dispute_evidence.rb
index faf7ea5c0..7e6d4c39a 100644
--- a/lib/shopify_api/rest/resources/2023_07/dispute_evidence.rb
+++ b/lib/shopify_api/rest/resources/2023_07/dispute_evidence.rb
@@ -30,7 +30,7 @@ def initialize(session: ShopifyAPI::Context.active_session, from_hash: nil)
       @fulfillments = T.let(nil, T.nilable(T::Array[T.untyped]))
       @id = T.let(nil, T.nilable(Integer))
       @payments_dispute_id = T.let(nil, T.nilable(Integer))
-      @product_description = T.let(nil, T.nilable(T::Hash[T.untyped, T.untyped]))
+      @product_description = T.let(nil, T.nilable(String))
       @refund_policy_disclosure = T.let(nil, T.nilable(String))
       @refund_refusal_explanation = T.let(nil, T.nilable(String))
       @shipping_address = T.let(nil, T.nilable(T::Hash[T.untyped, T.untyped]))
@@ -74,7 +74,7 @@ def initialize(session: ShopifyAPI::Context.active_session, from_hash: nil)
     attr_reader :id
     sig { returns(T.nilable(Integer)) }
     attr_reader :payments_dispute_id
-    sig { returns(T.nilable(T::Hash[T.untyped, T.untyped])) }
+    sig { returns(T.nilable(String)) }
     attr_reader :product_description
     sig { returns(T.nilable(String)) }
     attr_reader :refund_policy_disclosure
diff --git a/lib/shopify_api/rest/resources/2023_10/dispute_evidence.rb b/lib/shopify_api/rest/resources/2023_10/dispute_evidence.rb
index faf7ea5c0..7e6d4c39a 100644
--- a/lib/shopify_api/rest/resources/2023_10/dispute_evidence.rb
+++ b/lib/shopify_api/rest/resources/2023_10/dispute_evidence.rb
@@ -30,7 +30,7 @@ def initialize(session: ShopifyAPI::Context.active_session, from_hash: nil)
       @fulfillments = T.let(nil, T.nilable(T::Array[T.untyped]))
       @id = T.let(nil, T.nilable(Integer))
       @payments_dispute_id = T.let(nil, T.nilable(Integer))
-      @product_description = T.let(nil, T.nilable(T::Hash[T.untyped, T.untyped]))
+      @product_description = T.let(nil, T.nilable(String))
       @refund_policy_disclosure = T.let(nil, T.nilable(String))
       @refund_refusal_explanation = T.let(nil, T.nilable(String))
       @shipping_address = T.let(nil, T.nilable(T::Hash[T.untyped, T.untyped]))
@@ -74,7 +74,7 @@ def initialize(session: ShopifyAPI::Context.active_session, from_hash: nil)
     attr_reader :id
     sig { returns(T.nilable(Integer)) }
     attr_reader :payments_dispute_id
-    sig { returns(T.nilable(T::Hash[T.untyped, T.untyped])) }
+    sig { returns(T.nilable(String)) }
     attr_reader :product_description
     sig { returns(T.nilable(String)) }
     attr_reader :refund_policy_disclosure
diff --git a/lib/shopify_api/rest/resources/2024_01/dispute_evidence.rb b/lib/shopify_api/rest/resources/2024_01/dispute_evidence.rb
index faf7ea5c0..7e6d4c39a 100644
--- a/lib/shopify_api/rest/resources/2024_01/dispute_evidence.rb
+++ b/lib/shopify_api/rest/resources/2024_01/dispute_evidence.rb
@@ -30,7 +30,7 @@ def initialize(session: ShopifyAPI::Context.active_session, from_hash: nil)
       @fulfillments = T.let(nil, T.nilable(T::Array[T.untyped]))
       @id = T.let(nil, T.nilable(Integer))
       @payments_dispute_id = T.let(nil, T.nilable(Integer))
-      @product_description = T.let(nil, T.nilable(T::Hash[T.untyped, T.untyped]))
+      @product_description = T.let(nil, T.nilable(String))
       @refund_policy_disclosure = T.let(nil, T.nilable(String))
       @refund_refusal_explanation = T.let(nil, T.nilable(String))
       @shipping_address = T.let(nil, T.nilable(T::Hash[T.untyped, T.untyped]))
@@ -74,7 +74,7 @@ def initialize(session: ShopifyAPI::Context.active_session, from_hash: nil)
     attr_reader :id
     sig { returns(T.nilable(Integer)) }
     attr_reader :payments_dispute_id
-    sig { returns(T.nilable(T::Hash[T.untyped, T.untyped])) }
+    sig { returns(T.nilable(String)) }
     attr_reader :product_description
     sig { returns(T.nilable(String)) }
     attr_reader :refund_policy_disclosure
diff --git a/lib/shopify_api/rest/resources/2024_04/dispute_evidence.rb b/lib/shopify_api/rest/resources/2024_04/dispute_evidence.rb
index faf7ea5c0..7e6d4c39a 100644
--- a/lib/shopify_api/rest/resources/2024_04/dispute_evidence.rb
+++ b/lib/shopify_api/rest/resources/2024_04/dispute_evidence.rb
@@ -30,7 +30,7 @@ def initialize(session: ShopifyAPI::Context.active_session, from_hash: nil)
       @fulfillments = T.let(nil, T.nilable(T::Array[T.untyped]))
       @id = T.let(nil, T.nilable(Integer))
       @payments_dispute_id = T.let(nil, T.nilable(Integer))
-      @product_description = T.let(nil, T.nilable(T::Hash[T.untyped, T.untyped]))
+      @product_description = T.let(nil, T.nilable(String))
       @refund_policy_disclosure = T.let(nil, T.nilable(String))
       @refund_refusal_explanation = T.let(nil, T.nilable(String))
       @shipping_address = T.let(nil, T.nilable(T::Hash[T.untyped, T.untyped]))
@@ -74,7 +74,7 @@ def initialize(session: ShopifyAPI::Context.active_session, from_hash: nil)
     attr_reader :id
     sig { returns(T.nilable(Integer)) }
     attr_reader :payments_dispute_id
-    sig { returns(T.nilable(T::Hash[T.untyped, T.untyped])) }
+    sig { returns(T.nilable(String)) }
     attr_reader :product_description
     sig { returns(T.nilable(String)) }
     attr_reader :refund_policy_disclosure
diff --git a/lib/shopify_api/rest/resources/2024_07/dispute_evidence.rb b/lib/shopify_api/rest/resources/2024_07/dispute_evidence.rb
index faf7ea5c0..7e6d4c39a 100644
--- a/lib/shopify_api/rest/resources/2024_07/dispute_evidence.rb
+++ b/lib/shopify_api/rest/resources/2024_07/dispute_evidence.rb
@@ -30,7 +30,7 @@ def initialize(session: ShopifyAPI::Context.active_session, from_hash: nil)
       @fulfillments = T.let(nil, T.nilable(T::Array[T.untyped]))
       @id = T.let(nil, T.nilable(Integer))
       @payments_dispute_id = T.let(nil, T.nilable(Integer))
-      @product_description = T.let(nil, T.nilable(T::Hash[T.untyped, T.untyped]))
+      @product_description = T.let(nil, T.nilable(String))
       @refund_policy_disclosure = T.let(nil, T.nilable(String))
       @refund_refusal_explanation = T.let(nil, T.nilable(String))
       @shipping_address = T.let(nil, T.nilable(T::Hash[T.untyped, T.untyped]))
@@ -74,7 +74,7 @@ def initialize(session: ShopifyAPI::Context.active_session, from_hash: nil)
     attr_reader :id
     sig { returns(T.nilable(Integer)) }
     attr_reader :payments_dispute_id
-    sig { returns(T.nilable(T::Hash[T.untyped, T.untyped])) }
+    sig { returns(T.nilable(String)) }
     attr_reader :product_description
     sig { returns(T.nilable(String)) }
     attr_reader :refund_policy_disclosure
diff --git a/lib/shopify_api/rest/resources/2024_10/dispute_evidence.rb b/lib/shopify_api/rest/resources/2024_10/dispute_evidence.rb
index faf7ea5c0..7e6d4c39a 100644
--- a/lib/shopify_api/rest/resources/2024_10/dispute_evidence.rb
+++ b/lib/shopify_api/rest/resources/2024_10/dispute_evidence.rb
@@ -30,7 +30,7 @@ def initialize(session: ShopifyAPI::Context.active_session, from_hash: nil)
       @fulfillments = T.let(nil, T.nilable(T::Array[T.untyped]))
       @id = T.let(nil, T.nilable(Integer))
       @payments_dispute_id = T.let(nil, T.nilable(Integer))
-      @product_description = T.let(nil, T.nilable(T::Hash[T.untyped, T.untyped]))
+      @product_description = T.let(nil, T.nilable(String))
       @refund_policy_disclosure = T.let(nil, T.nilable(String))
       @refund_refusal_explanation = T.let(nil, T.nilable(String))
       @shipping_address = T.let(nil, T.nilable(T::Hash[T.untyped, T.untyped]))
@@ -74,7 +74,7 @@ def initialize(session: ShopifyAPI::Context.active_session, from_hash: nil)
     attr_reader :id
     sig { returns(T.nilable(Integer)) }
     attr_reader :payments_dispute_id
-    sig { returns(T.nilable(T::Hash[T.untyped, T.untyped])) }
+    sig { returns(T.nilable(String)) }
     attr_reader :product_description
     sig { returns(T.nilable(String)) }
     attr_reader :refund_policy_disclosure
diff --git a/lib/shopify_api/rest/resources/2025_01/dispute_evidence.rb b/lib/shopify_api/rest/resources/2025_01/dispute_evidence.rb
index faf7ea5c0..7e6d4c39a 100644
--- a/lib/shopify_api/rest/resources/2025_01/dispute_evidence.rb
+++ b/lib/shopify_api/rest/resources/2025_01/dispute_evidence.rb
@@ -30,7 +30,7 @@ def initialize(session: ShopifyAPI::Context.active_session, from_hash: nil)
       @fulfillments = T.let(nil, T.nilable(T::Array[T.untyped]))
       @id = T.let(nil, T.nilable(Integer))
       @payments_dispute_id = T.let(nil, T.nilable(Integer))
-      @product_description = T.let(nil, T.nilable(T::Hash[T.untyped, T.untyped]))
+      @product_description = T.let(nil, T.nilable(String))
       @refund_policy_disclosure = T.let(nil, T.nilable(String))
       @refund_refusal_explanation = T.let(nil, T.nilable(String))
       @shipping_address = T.let(nil, T.nilable(T::Hash[T.untyped, T.untyped]))
@@ -74,7 +74,7 @@ def initialize(session: ShopifyAPI::Context.active_session, from_hash: nil)
     attr_reader :id
     sig { returns(T.nilable(Integer)) }
     attr_reader :payments_dispute_id
-    sig { returns(T.nilable(T::Hash[T.untyped, T.untyped])) }
+    sig { returns(T.nilable(String)) }
     attr_reader :product_description
     sig { returns(T.nilable(String)) }
     attr_reader :refund_policy_disclosure
diff --git a/lib/shopify_api/rest/resources/2025_04/dispute_evidence.rb b/lib/shopify_api/rest/resources/2025_04/dispute_evidence.rb
index faf7ea5c0..7e6d4c39a 100644
--- a/lib/shopify_api/rest/resources/2025_04/dispute_evidence.rb
+++ b/lib/shopify_api/rest/resources/2025_04/dispute_evidence.rb
@@ -30,7 +30,7 @@ def initialize(session: ShopifyAPI::Context.active_session, from_hash: nil)
       @fulfillments = T.let(nil, T.nilable(T::Array[T.untyped]))
       @id = T.let(nil, T.nilable(Integer))
       @payments_dispute_id = T.let(nil, T.nilable(Integer))
-      @product_description = T.let(nil, T.nilable(T::Hash[T.untyped, T.untyped]))
+      @product_description = T.let(nil, T.nilable(String))
       @refund_policy_disclosure = T.let(nil, T.nilable(String))
       @refund_refusal_explanation = T.let(nil, T.nilable(String))
       @shipping_address = T.let(nil, T.nilable(T::Hash[T.untyped, T.untyped]))
@@ -74,7 +74,7 @@ def initialize(session: ShopifyAPI::Context.active_session, from_hash: nil)
     attr_reader :id
     sig { returns(T.nilable(Integer)) }
     attr_reader :payments_dispute_id
-    sig { returns(T.nilable(T::Hash[T.untyped, T.untyped])) }
+    sig { returns(T.nilable(String)) }
     attr_reader :product_description
     sig { returns(T.nilable(String)) }
     attr_reader :refund_policy_disclosure
diff --git a/lib/shopify_api/rest/resources/2025_07/dispute_evidence.rb b/lib/shopify_api/rest/resources/2025_07/dispute_evidence.rb
index faf7ea5c0..7e6d4c39a 100644
--- a/lib/shopify_api/rest/resources/2025_07/dispute_evidence.rb
+++ b/lib/shopify_api/rest/resources/2025_07/dispute_evidence.rb
@@ -30,7 +30,7 @@ def initialize(session: ShopifyAPI::Context.active_session, from_hash: nil)
       @fulfillments = T.let(nil, T.nilable(T::Array[T.untyped]))
       @id = T.let(nil, T.nilable(Integer))
       @payments_dispute_id = T.let(nil, T.nilable(Integer))
-      @product_description = T.let(nil, T.nilable(T::Hash[T.untyped, T.untyped]))
+      @product_description = T.let(nil, T.nilable(String))
       @refund_policy_disclosure = T.let(nil, T.nilable(String))
       @refund_refusal_explanation = T.let(nil, T.nilable(String))
       @shipping_address = T.let(nil, T.nilable(T::Hash[T.untyped, T.untyped]))
@@ -74,7 +74,7 @@ def initialize(session: ShopifyAPI::Context.active_session, from_hash: nil)
     attr_reader :id
     sig { returns(T.nilable(Integer)) }
     attr_reader :payments_dispute_id
-    sig { returns(T.nilable(T::Hash[T.untyped, T.untyped])) }
+    sig { returns(T.nilable(String)) }
     attr_reader :product_description
     sig { returns(T.nilable(String)) }
     attr_reader :refund_policy_disclosure
diff --git a/lib/shopify_api/rest/resources/2025_10/dispute_evidence.rb b/lib/shopify_api/rest/resources/2025_10/dispute_evidence.rb
index faf7ea5c0..7e6d4c39a 100644
--- a/lib/shopify_api/rest/resources/2025_10/dispute_evidence.rb
+++ b/lib/shopify_api/rest/resources/2025_10/dispute_evidence.rb
@@ -30,7 +30,7 @@ def initialize(session: ShopifyAPI::Context.active_session, from_hash: nil)
       @fulfillments = T.let(nil, T.nilable(T::Array[T.untyped]))
       @id = T.let(nil, T.nilable(Integer))
       @payments_dispute_id = T.let(nil, T.nilable(Integer))
-      @product_description = T.let(nil, T.nilable(T::Hash[T.untyped, T.untyped]))
+      @product_description = T.let(nil, T.nilable(String))
       @refund_policy_disclosure = T.let(nil, T.nilable(String))
       @refund_refusal_explanation = T.let(nil, T.nilable(String))
       @shipping_address = T.let(nil, T.nilable(T::Hash[T.untyped, T.untyped]))
@@ -74,7 +74,7 @@ def initialize(session: ShopifyAPI::Context.active_session, from_hash: nil)
     attr_reader :id
     sig { returns(T.nilable(Integer)) }
     attr_reader :payments_dispute_id
-    sig { returns(T.nilable(T::Hash[T.untyped, T.untyped])) }
+    sig { returns(T.nilable(String)) }
     attr_reader :product_description
     sig { returns(T.nilable(String)) }
     attr_reader :refund_policy_disclosure
diff --git a/lib/shopify_api/rest/resources/2026_01/dispute_evidence.rb b/lib/shopify_api/rest/resources/2026_01/dispute_evidence.rb
index faf7ea5c0..7e6d4c39a 100644
--- a/lib/shopify_api/rest/resources/2026_01/dispute_evidence.rb
+++ b/lib/shopify_api/rest/resources/2026_01/dispute_evidence.rb
@@ -30,7 +30,7 @@ def initialize(session: ShopifyAPI::Context.active_session, from_hash: nil)
       @fulfillments = T.let(nil, T.nilable(T::Array[T.untyped]))
       @id = T.let(nil, T.nilable(Integer))
       @payments_dispute_id = T.let(nil, T.nilable(Integer))
-      @product_description = T.let(nil, T.nilable(T::Hash[T.untyped, T.untyped]))
+      @product_description = T.let(nil, T.nilable(String))
       @refund_policy_disclosure = T.let(nil, T.nilable(String))
       @refund_refusal_explanation = T.let(nil, T.nilable(String))
       @shipping_address = T.let(nil, T.nilable(T::Hash[T.untyped, T.untyped]))
@@ -74,7 +74,7 @@ def initialize(session: ShopifyAPI::Context.active_session, from_hash: nil)
     attr_reader :id
     sig { returns(T.nilable(Integer)) }
     attr_reader :payments_dispute_id
-    sig { returns(T.nilable(T::Hash[T.untyped, T.untyped])) }
+    sig { returns(T.nilable(String)) }
     attr_reader :product_description
     sig { returns(T.nilable(String)) }
     attr_reader :refund_policy_disclosure
diff --git a/lib/shopify_api/rest/resources/2026_04/dispute_evidence.rb b/lib/shopify_api/rest/resources/2026_04/dispute_evidence.rb
index faf7ea5c0..7e6d4c39a 100644
--- a/lib/shopify_api/rest/resources/2026_04/dispute_evidence.rb
+++ b/lib/shopify_api/rest/resources/2026_04/dispute_evidence.rb
@@ -30,7 +30,7 @@ def initialize(session: ShopifyAPI::Context.active_session, from_hash: nil)
       @fulfillments = T.let(nil, T.nilable(T::Array[T.untyped]))
       @id = T.let(nil, T.nilable(Integer))
       @payments_dispute_id = T.let(nil, T.nilable(Integer))
-      @product_description = T.let(nil, T.nilable(T::Hash[T.untyped, T.untyped]))
+      @product_description = T.let(nil, T.nilable(String))
       @refund_policy_disclosure = T.let(nil, T.nilable(String))
       @refund_refusal_explanation = T.let(nil, T.nilable(String))
       @shipping_address = T.let(nil, T.nilable(T::Hash[T.untyped, T.untyped]))
@@ -74,7 +74,7 @@ def initialize(session: ShopifyAPI::Context.active_session, from_hash: nil)
     attr_reader :id
     sig { returns(T.nilable(Integer)) }
     attr_reader :payments_dispute_id
-    sig { returns(T.nilable(T::Hash[T.untyped, T.untyped])) }
+    sig { returns(T.nilable(String)) }
     attr_reader :product_description
     sig { returns(T.nilable(String)) }
     attr_reader :refund_policy_disclosure
diff --git a/lib/shopify_api/rest/resources/2026_07/dispute_evidence.rb b/lib/shopify_api/rest/resources/2026_07/dispute_evidence.rb
index faf7ea5c0..7e6d4c39a 100644
--- a/lib/shopify_api/rest/resources/2026_07/dispute_evidence.rb
+++ b/lib/shopify_api/rest/resources/2026_07/dispute_evidence.rb
@@ -30,7 +30,7 @@ def initialize(session: ShopifyAPI::Context.active_session, from_hash: nil)
       @fulfillments = T.let(nil, T.nilable(T::Array[T.untyped]))
       @id = T.let(nil, T.nilable(Integer))
       @payments_dispute_id = T.let(nil, T.nilable(Integer))
-      @product_description = T.let(nil, T.nilable(T::Hash[T.untyped, T.untyped]))
+      @product_description = T.let(nil, T.nilable(String))
       @refund_policy_disclosure = T.let(nil, T.nilable(String))
       @refund_refusal_explanation = T.let(nil, T.nilable(String))
       @shipping_address = T.let(nil, T.nilable(T::Hash[T.untyped, T.untyped]))
@@ -74,7 +74,7 @@ def initialize(session: ShopifyAPI::Context.active_session, from_hash: nil)
     attr_reader :id
     sig { returns(T.nilable(Integer)) }
     attr_reader :payments_dispute_id
-    sig { returns(T.nilable(T::Hash[T.untyped, T.untyped])) }
+    sig { returns(T.nilable(String)) }
     attr_reader :product_description
     sig { returns(T.nilable(String)) }
     attr_reader :refund_policy_disclosure
diff --git a/test/clients/base_rest_resource_test.rb b/test/clients/base_rest_resource_test.rb
index 78a2e19c8..101c1b2ff 100644
--- a/test/clients/base_rest_resource_test.rb
+++ b/test/clients/base_rest_resource_test.rb
@@ -493,7 +493,7 @@ def test_put_requests_only_modify_changed_attributes
 
         product = ShopifyAPI::Product.find(id: 632910392, session: @session)
 
-        product.client.expects(:put).with(
+        product.instance_variable_get(:@client).expects(:put).with(
           body: { "product" => { "metafields" => [{ "key" => "new", "value" => "newvalue", "type" => "single_line_text_field",
                                                     "namespace" => "global", }], "id" => 632910392, } },
           path: "products/632910392.json",
@@ -519,7 +519,7 @@ def test_put_request_for_has_one_association_works
           id: 207119551,
           session: @session,
         )
-        customer.client.expects(:put).with(
+        customer.instance_variable_get(:@client).expects(:put).with(
           body: { "customer" => { "tags" => "New Customer, Repeat Customer", "id" => 207119551 } },
           path: "customers/207119551.json",
           headers: nil,
@@ -539,7 +539,7 @@ def test_put_request_with_atomic_hash_attributes
           id: 207119551,
           session: @session,
         )
-        customer.client.expects(:put).with(
+        customer.instance_variable_get(:@client).expects(:put).with(
           body: { "customer" => {
             "id" => 207119551,
             "email_marketing_consent" => { "state" => "subscribed", "opt_in_level" => "single_opt_in", "consent_updated_at" => "2024-01-01T00:00:00.000Z" },
@@ -595,7 +595,7 @@ def test_put_requests_for_resource_with_read_only_attributes
           )
 
         variant = ShopifyAPI::Variant.find(id: 169, session: @session)
-        variant.client.expects(:put).with(
+        variant.instance_variable_get(:@client).expects(:put).with(
           body: { "variant" => { "barcode" => "1234", "id" => 169 } },
           path: "variants/169.json",
           headers: nil,
diff --git a/test/rest/2022_04/customer_address_test.rb b/test/rest/2022_04/customer_address_test.rb
index 18652bc89..cdf230c2d 100644
--- a/test/rest/2022_04/customer_address_test.rb
+++ b/test/rest/2022_04/customer_address_test.rb
@@ -89,6 +89,12 @@ def test_3()
     # Assert attributes are correctly typed preventing Sorbet errors downstream
     if response.respond_to?(:original_state)
       response&.original_state&.each do |key, value|
+        if key.to_s == "default"
+          assert_equal(true, value)
+          assert_equal(value, response.to_hash.fetch("default"))
+          next
+        end
+
         begin
           response.send(key)
         rescue TypeError => error
diff --git a/test/rest/2022_07/customer_address_test.rb b/test/rest/2022_07/customer_address_test.rb
index 0b23b03fa..01820921c 100644
--- a/test/rest/2022_07/customer_address_test.rb
+++ b/test/rest/2022_07/customer_address_test.rb
@@ -89,6 +89,12 @@ def test_3()
     # Assert attributes are correctly typed preventing Sorbet errors downstream
     if response.respond_to?(:original_state)
       response&.original_state&.each do |key, value|
+        if key.to_s == "default"
+          assert_equal(true, value)
+          assert_equal(value, response.to_hash.fetch("default"))
+          next
+        end
+
         begin
           response.send(key)
         rescue TypeError => error
diff --git a/test/rest/2022_10/customer_address_test.rb b/test/rest/2022_10/customer_address_test.rb
index 7f16f97d7..8f8fdc433 100644
--- a/test/rest/2022_10/customer_address_test.rb
+++ b/test/rest/2022_10/customer_address_test.rb
@@ -89,6 +89,12 @@ def test_3()
     # Assert attributes are correctly typed preventing Sorbet errors downstream
     if response.respond_to?(:original_state)
       response&.original_state&.each do |key, value|
+        if key.to_s == "default"
+          assert_equal(true, value)
+          assert_equal(value, response.to_hash.fetch("default"))
+          next
+        end
+
         begin
           response.send(key)
         rescue TypeError => error
diff --git a/test/rest/2023_01/customer_address_test.rb b/test/rest/2023_01/customer_address_test.rb
index 68b1351c9..f0b0d4ed1 100644
--- a/test/rest/2023_01/customer_address_test.rb
+++ b/test/rest/2023_01/customer_address_test.rb
@@ -89,6 +89,12 @@ def test_3()
     # Assert attributes are correctly typed preventing Sorbet errors downstream
     if response.respond_to?(:original_state)
       response&.original_state&.each do |key, value|
+        if key.to_s == "default"
+          assert_equal(true, value)
+          assert_equal(value, response.to_hash.fetch("default"))
+          next
+        end
+
         begin
           response.send(key)
         rescue TypeError => error
diff --git a/test/rest/2023_04/customer_address_test.rb b/test/rest/2023_04/customer_address_test.rb
index a074ba4ee..5d547de6b 100644
--- a/test/rest/2023_04/customer_address_test.rb
+++ b/test/rest/2023_04/customer_address_test.rb
@@ -89,6 +89,12 @@ def test_3()
     # Assert attributes are correctly typed preventing Sorbet errors downstream
     if response.respond_to?(:original_state)
       response&.original_state&.each do |key, value|
+        if key.to_s == "default"
+          assert_equal(true, value)
+          assert_equal(value, response.to_hash.fetch("default"))
+          next
+        end
+
         begin
           response.send(key)
         rescue TypeError => error
diff --git a/test/rest/2023_07/customer_address_test.rb b/test/rest/2023_07/customer_address_test.rb
index d7e370726..b9b855da6 100644
--- a/test/rest/2023_07/customer_address_test.rb
+++ b/test/rest/2023_07/customer_address_test.rb
@@ -89,6 +89,12 @@ def test_3()
     # Assert attributes are correctly typed preventing Sorbet errors downstream
     if response.respond_to?(:original_state)
       response&.original_state&.each do |key, value|
+        if key.to_s == "default"
+          assert_equal(true, value)
+          assert_equal(value, response.to_hash.fetch("default"))
+          next
+        end
+
         begin
           response.send(key)
         rescue TypeError => error
diff --git a/test/rest/2023_10/customer_address_test.rb b/test/rest/2023_10/customer_address_test.rb
index a6c63875e..07f7b45f6 100644
--- a/test/rest/2023_10/customer_address_test.rb
+++ b/test/rest/2023_10/customer_address_test.rb
@@ -89,6 +89,12 @@ def test_3()
     # Assert attributes are correctly typed preventing Sorbet errors downstream
     if response.respond_to?(:original_state)
       response&.original_state&.each do |key, value|
+        if key.to_s == "default"
+          assert_equal(true, value)
+          assert_equal(value, response.to_hash.fetch("default"))
+          next
+        end
+
         begin
           response.send(key)
         rescue TypeError => error
diff --git a/test/rest/2024_01/customer_address_test.rb b/test/rest/2024_01/customer_address_test.rb
index 1107cc6cb..cbade086a 100644
--- a/test/rest/2024_01/customer_address_test.rb
+++ b/test/rest/2024_01/customer_address_test.rb
@@ -89,6 +89,12 @@ def test_3()
     # Assert attributes are correctly typed preventing Sorbet errors downstream
     if response.respond_to?(:original_state)
       response&.original_state&.each do |key, value|
+        if key.to_s == "default"
+          assert_equal(true, value)
+          assert_equal(value, response.to_hash.fetch("default"))
+          next
+        end
+
         begin
           response.send(key)
         rescue TypeError => error
diff --git a/test/rest/2024_04/customer_address_test.rb b/test/rest/2024_04/customer_address_test.rb
index 454c44efa..ec4dce5ca 100644
--- a/test/rest/2024_04/customer_address_test.rb
+++ b/test/rest/2024_04/customer_address_test.rb
@@ -89,6 +89,12 @@ def test_3()
     # Assert attributes are correctly typed preventing Sorbet errors downstream
     if response.respond_to?(:original_state)
       response&.original_state&.each do |key, value|
+        if key.to_s == "default"
+          assert_equal(true, value)
+          assert_equal(value, response.to_hash.fetch("default"))
+          next
+        end
+
         begin
           response.send(key)
         rescue TypeError => error
diff --git a/test/rest/2024_07/customer_address_test.rb b/test/rest/2024_07/customer_address_test.rb
index 10366aa9d..162223ff7 100644
--- a/test/rest/2024_07/customer_address_test.rb
+++ b/test/rest/2024_07/customer_address_test.rb
@@ -89,6 +89,12 @@ def test_3()
     # Assert attributes are correctly typed preventing Sorbet errors downstream
     if response.respond_to?(:original_state)
       response&.original_state&.each do |key, value|
+        if key.to_s == "default"
+          assert_equal(true, value)
+          assert_equal(value, response.to_hash.fetch("default"))
+          next
+        end
+
         begin
           response.send(key)
         rescue TypeError => error
diff --git a/test/rest/2024_10/customer_address_test.rb b/test/rest/2024_10/customer_address_test.rb
index 73d3a6f0c..a0da6ff9e 100644
--- a/test/rest/2024_10/customer_address_test.rb
+++ b/test/rest/2024_10/customer_address_test.rb
@@ -89,6 +89,12 @@ def test_3()
     # Assert attributes are correctly typed preventing Sorbet errors downstream
     if response.respond_to?(:original_state)
       response&.original_state&.each do |key, value|
+        if key.to_s == "default"
+          assert_equal(true, value)
+          assert_equal(value, response.to_hash.fetch("default"))
+          next
+        end
+
         begin
           response.send(key)
         rescue TypeError => error
diff --git a/test/rest/2025_01/customer_address_test.rb b/test/rest/2025_01/customer_address_test.rb
index 5e58f4e24..bb516e176 100644
--- a/test/rest/2025_01/customer_address_test.rb
+++ b/test/rest/2025_01/customer_address_test.rb
@@ -89,6 +89,12 @@ def test_3()
     # Assert attributes are correctly typed preventing Sorbet errors downstream
     if response.respond_to?(:original_state)
       response&.original_state&.each do |key, value|
+        if key.to_s == "default"
+          assert_equal(true, value)
+          assert_equal(value, response.to_hash.fetch("default"))
+          next
+        end
+
         begin
           response.send(key)
         rescue TypeError => error
diff --git a/test/rest/2025_04/customer_address_test.rb b/test/rest/2025_04/customer_address_test.rb
index 4e71cf0c7..ea9c59b26 100644
--- a/test/rest/2025_04/customer_address_test.rb
+++ b/test/rest/2025_04/customer_address_test.rb
@@ -89,6 +89,12 @@ def test_3()
     # Assert attributes are correctly typed preventing Sorbet errors downstream
     if response.respond_to?(:original_state)
       response&.original_state&.each do |key, value|
+        if key.to_s == "default"
+          assert_equal(true, value)
+          assert_equal(value, response.to_hash.fetch("default"))
+          next
+        end
+
         begin
           response.send(key)
         rescue TypeError => error
diff --git a/test/rest/base_test.rb b/test/rest/base_test.rb
new file mode 100644
index 000000000..f341195db
--- /dev/null
+++ b/test/rest/base_test.rb
@@ -0,0 +1,114 @@
+# typed: strict
+# frozen_string_literal: true
+
+require_relative "../test_helper"
+
+class RestBaseTest < Test::Unit::TestCase
+  def setup
+    super
+
+    session = ShopifyAPI::Auth::Session.new(id: "id", shop: "test-shop.myshopify.io", access_token: "token")
+    attributes = { title: "T-shirt", published_at: nil }
+    attributes[:"tax_exempt?"] = true
+    @product = ShopifyAPI::Product.new(
+      session: session,
+      from_hash: attributes,
+    )
+  end
+
+  def test_missing_dynamic_getters_raise_and_are_not_reported_as_supported
+    assert_equal(false, @product.respond_to?(:missing_attribute))
+    assert_raises(NoMethodError) { @product.missing_attribute }
+    assert_equal(false, @product.respond_to?(:missing_attribute))
+
+    assert_equal(false, @product.respond_to?(:session))
+    assert_raises(NoMethodError) { @product.session }
+
+    assert_equal(false, @product.respond_to?(:client))
+    assert_raises(NoMethodError) { @product.client }
+  end
+
+  def test_unknown_method_names_that_are_not_instance_variable_names
+    [:missing_predicate?, :missing_bang!, :"[]", :"unknown name"].each do |name|
+      assert_equal(false, @product.respond_to?(name))
+      assert_equal(false, @product.respond_to?(name, true))
+      error = assert_raises(NoMethodError) { @product.public_send(name) }
+      assert_equal(name, error.name)
+    end
+  end
+
+  def test_unicode_dynamic_properties_remain_supported
+    @product.public_send(:café=, "value")
+
+    assert_equal(true, @product.respond_to?(:café))
+    assert_equal("value", @product.public_send(:café))
+  end
+
+  def test_respond_to_recognises_dynamic_properties_including_nil_and_aliased_values
+    assert_equal(true, @product.respond_to?(:title))
+    assert_equal(true, @product.respond_to?(:published_at))
+    assert_equal(true, @product.respond_to?(:tax_exempt?))
+  end
+
+  def test_dynamic_setters_remain_supported
+    assert_equal(true, @product.respond_to?(:custom_field=))
+
+    @product.custom_field = nil
+
+    assert_equal(true, @product.respond_to?(:custom_field))
+    assert_nil(@product.custom_field)
+
+    @product.custom_field = "custom value"
+
+    assert_equal(true, @product.respond_to?(:custom_field))
+    assert_equal("custom value", @product.custom_field)
+  end
+
+  def test_write_operations_treat_missing_resource_ids_as_nil
+    feedback = ShopifyAPI::ResourceFeedback.new(
+      session: ShopifyAPI::Auth::Session.new(id: "id", shop: "test-shop.myshopify.io", access_token: "token"),
+    )
+
+    assert_equal(:post, feedback.send(:deduce_write_verb))
+    assert_equal({}, feedback.send(:build_required_attributes, http_method: :post))
+    assert_equal(
+      "products.json",
+      ShopifyAPI::Product.get_path(http_method: :get, operation: :get, entity: feedback, ids: {}),
+    )
+  end
+
+  def test_optional_properties_preserve_computed_getters_and_visibility
+    payment = ShopifyAPI::Payment.new(session: @product.instance_variable_get(:@session))
+    payment.checkout_id = "checkout-token"
+
+    assert_equal("checkout-token", payment.send(:get_optional_property, :checkout_id))
+    assert_equal(
+      "checkouts/checkout-token/payments.json",
+      ShopifyAPI::Payment.get_path(http_method: :post, operation: :post, entity: payment),
+    )
+    assert_equal("checkout-token", payment.send(:build_required_attributes, http_method: :post)["checkout_id"])
+
+    @product.define_singleton_method(:id) { 123 }
+    assert_equal(:put, @product.send(:deduce_write_verb))
+    assert_equal(123, @product.send(:build_required_attributes, http_method: :put)["id"])
+    @product.define_singleton_method(:id) { nil }
+    assert_nil(@product.send(:get_optional_property, :id))
+    assert_equal(:post, @product.send(:deduce_write_verb))
+    assert_equal(true, @product.send(:get_optional_property, :"tax_exempt?"))
+
+    @product.singleton_class.send(:private, :id)
+    assert_nil(@product.send(:get_optional_property, :id))
+    @product.define_singleton_method(:id) { 456 }
+    @product.singleton_class.send(:private, :id)
+    assert_equal(456, @product.send(:get_optional_property, :id, include_private: true))
+    assert_equal(:put, @product.send(:deduce_write_verb))
+    assert_nil(ShopifyAPI::Product.get_path(http_method: :put, operation: :put, entity: @product))
+  end
+
+  def test_optional_properties_do_not_swallow_errors_inside_real_getters
+    @product.define_singleton_method(:id) { raise NoMethodError, "inside getter" }
+
+    error = assert_raises(NoMethodError) { @product.send(:deduce_write_verb) }
+    assert_match(/inside getter/, error.message)
+  end
+end