1 files changed, 31 insertions, 2 deletions
diff --git a/lib/dispatch/adapter/interface/response.rb b/lib/dispatch/adapter/interface/response.rb
index b4ba3eb..391b033 100644
--- a/lib/dispatch/adapter/interface/response.rb
+++ b/lib/dispatch/adapter/interface/response.rb
@@ -2,18 +2,47 @@
 
 module Dispatch
   module Adapter
+    # stop_reason ∈
+    #   :end_turn       — natural completion
+    #   :max_tokens     — output truncated by max_tokens
+    #   :tool_use       — assistant emitted tool calls
+    #   :pause_turn     — provider asked us to resubmit (Anthropic)
+    #   :refusal        — provider refused to answer
+    #   :sensitive      — output blocked by safety filters
+    #   :error          — adapter-level failure
     Response = Struct.new(:content, :tool_calls, :model, :stop_reason, :usage, keyword_init: true) do
       def initialize(model:, stop_reason:, usage:, content: nil, tool_calls: [])
         super
       end
     end
 
-    Usage = Struct.new(:input_tokens, :output_tokens, :cache_read_tokens, :cache_creation_tokens, keyword_init: true) do
-      def initialize(input_tokens:, output_tokens:, cache_read_tokens: 0, cache_creation_tokens: 0)
+    UsageCost = Struct.new(
+      :input, :output, :cache_read, :cache_write, :total,
+      keyword_init: true
+    ) do
+      def initialize(input: 0.0, output: 0.0, cache_read: 0.0,
+                     cache_write: 0.0, total: 0.0)
         super
       end
     end
 
+    Usage = Struct.new(
+      :input_tokens, :output_tokens,
+      :cache_read_tokens, :cache_creation_tokens,
+      :reasoning_tokens, :premium_requests, :cost,
+      keyword_init: true
+    ) do
+      def initialize(input_tokens:, output_tokens:,
+                     cache_read_tokens: 0, cache_creation_tokens: 0,
+                     reasoning_tokens: 0, premium_requests: nil, cost: nil)
+        super
+      end
+    end
+
+    # Recognised :type values:
+    #   :text_start, :text_delta, :text_end
+    #   :thinking_start, :thinking_delta, :thinking_end
+    #   :tool_use_start, :tool_use_delta, :tool_use_end
     StreamDelta = Struct.new(:type, :text, :tool_call_id, :tool_name, :argument_delta, keyword_init: true) do
       def initialize(type:, text: nil, tool_call_id: nil, tool_name: nil, argument_delta: nil)
         super