diff --git a/lib/openai.rb b/lib/openai.rb
index 7a735871..3106b191 100644
--- a/lib/openai.rb
+++ b/lib/openai.rb
@@ -36,7 +36,6 @@
 # Package files.
 require_relative "openai/version"
 require_relative "openai/util"
-require_relative "openai/extern"
 require_relative "openai/base_model"
 require_relative "openai/base_page"
 require_relative "openai/base_stream"
diff --git a/lib/openai/base_model.rb b/lib/openai/base_model.rb
index 2d37a563..20a05eb9 100644
--- a/lib/openai/base_model.rb
+++ b/lib/openai/base_model.rb
@@ -1165,9 +1165,6 @@ def initialize(data = {})
       end
     end
 
-    # @return [String]
-    def to_s = @data.to_s
-
     # @return [String]
     def inspect
       rows = self.class.known_fields.keys.map do
diff --git a/lib/openai/extern.rb b/lib/openai/extern.rb
deleted file mode 100644
index 1ab41492..00000000
--- a/lib/openai/extern.rb
+++ /dev/null
@@ -1,7 +0,0 @@
-# frozen_string_literal: true
-
-module OpenAI
-  # @api private
-  module Extern
-  end
-end
diff --git a/rbi/lib/openai/base_client.rbi b/rbi/lib/openai/base_client.rbi
index 92d2484d..580d6b5b 100644
--- a/rbi/lib/openai/base_client.rbi
+++ b/rbi/lib/openai/base_client.rbi
@@ -84,7 +84,7 @@ module OpenAI
     end
 
     # @api private
-    sig { returns(T.anything) }
+    sig { returns(OpenAI::PooledNetRequester) }
     attr_accessor :requester
 
     # @api private
diff --git a/rbi/lib/openai/base_model.rbi b/rbi/lib/openai/base_model.rbi
index 0f1d214f..412a31e7 100644
--- a/rbi/lib/openai/base_model.rbi
+++ b/rbi/lib/openai/base_model.rbi
@@ -38,7 +38,7 @@ module OpenAI
             OpenAI::Converter::Input
           )
         )
-          .returns(T.proc.returns(T.anything).void)
+          .returns(T.proc.returns(T.anything))
       end
       def self.type_info(spec)
       end
@@ -597,10 +597,6 @@ module OpenAI
     def self.new(data = {})
     end
 
-    sig { returns(String) }
-    def to_s
-    end
-
     sig { returns(String) }
     def inspect
     end
diff --git a/rbi/lib/openai/extern.rbi b/rbi/lib/openai/extern.rbi
deleted file mode 100644
index e5e18a8d..00000000
--- a/rbi/lib/openai/extern.rbi
+++ /dev/null
@@ -1,7 +0,0 @@
-# typed: strong
-
-module OpenAI
-  # @api private
-  module Extern
-  end
-end
diff --git a/sig/openai/base_client.rbs b/sig/openai/base_client.rbs
index 38596607..319bd07e 100644
--- a/sig/openai/base_client.rbs
+++ b/sig/openai/base_client.rbs
@@ -49,7 +49,7 @@ module OpenAI
     ) -> void
 
     # @api private
-    attr_accessor requester: top
+    attr_accessor requester: OpenAI::PooledNetRequester
 
     def initialize: (
       base_url: String,
diff --git a/sig/openai/base_model.rbs b/sig/openai/base_model.rbs
index 7f741683..a15f603e 100644
--- a/sig/openai/base_model.rbs
+++ b/sig/openai/base_model.rbs
@@ -243,8 +243,6 @@ module OpenAI
 
     def initialize: (?::Hash[Symbol, top] | self data) -> void
 
-    def to_s: -> String
-
     def inspect: -> String
   end
 end
diff --git a/sig/openai/extern.rbs b/sig/openai/extern.rbs
deleted file mode 100644
index 23069f69..00000000
--- a/sig/openai/extern.rbs
+++ /dev/null
@@ -1,4 +0,0 @@
-module OpenAI
-  module Extern
-  end
-end