7 files changed, 148 insertions, 0 deletions
diff --git a/lib/dispatch/adapter/interface/base.rb b/lib/dispatch/adapter/interface/base.rb
new file mode 100644
index 0000000..4b7a6ed
--- /dev/null
+++ b/lib/dispatch/adapter/interface/base.rb
@@ -0,0 +1,31 @@
+# frozen_string_literal: true
+
+module Dispatch
+  module Adapter
+    class Base
+      def chat(_messages, system: nil, tools: [], stream: false, max_tokens: nil, thinking: nil, &_block)
+        raise NotImplementedError, "#{self.class}#chat must be implemented"
+      end
+
+      def model_name
+        raise NotImplementedError, "#{self.class}#model_name must be implemented"
+      end
+
+      def count_tokens(_messages, system: nil, tools: []) # rubocop:disable Lint/UnusedMethodArgument
+        -1
+      end
+
+      def list_models
+        raise NotImplementedError, "#{self.class}#list_models must be implemented"
+      end
+
+      def provider_name
+        self.class.name
+      end
+
+      def max_context_tokens
+        nil
+      end
+    end
+  end
+end
diff --git a/lib/dispatch/adapter/interface/errors.rb b/lib/dispatch/adapter/interface/errors.rb
new file mode 100644
index 0000000..86f9c14
--- /dev/null
+++ b/lib/dispatch/adapter/interface/errors.rb
@@ -0,0 +1,30 @@
+# frozen_string_literal: true
+
+module Dispatch
+  module Adapter
+    class Error < StandardError
+      attr_reader :status_code, :provider
+
+      def initialize(message = nil, status_code: nil, provider: nil)
+        @status_code = status_code
+        @provider = provider
+        super(message)
+      end
+    end
+
+    class AuthenticationError < Error; end
+
+    class RateLimitError < Error
+      attr_reader :retry_after
+
+      def initialize(message = nil, status_code: nil, provider: nil, retry_after: nil)
+        @retry_after = retry_after
+        super(message, status_code:, provider:)
+      end
+    end
+
+    class ServerError < Error; end
+    class RequestError < Error; end
+    class ConnectionError < Error; end
+  end
+end
diff --git a/lib/dispatch/adapter/interface/message.rb b/lib/dispatch/adapter/interface/message.rb
new file mode 100644
index 0000000..eb51c99
--- /dev/null
+++ b/lib/dispatch/adapter/interface/message.rb
@@ -0,0 +1,31 @@
+# frozen_string_literal: true
+
+module Dispatch
+  module Adapter
+    Message = Struct.new(:role, :content, keyword_init: true)
+
+    TextBlock = Struct.new(:type, :text, keyword_init: true) do
+      def initialize(text:, type: "text")
+        super(type:, text:)
+      end
+    end
+
+    ImageBlock = Struct.new(:type, :source, :media_type, keyword_init: true) do
+      def initialize(source:, media_type:, type: "image")
+        super(type:, source:, media_type:)
+      end
+    end
+
+    ToolUseBlock = Struct.new(:type, :id, :name, :arguments, keyword_init: true) do
+      def initialize(id:, name:, arguments:, type: "tool_use")
+        super(type:, id:, name:, arguments:)
+      end
+    end
+
+    ToolResultBlock = Struct.new(:type, :tool_use_id, :content, :is_error, keyword_init: true) do
+      def initialize(tool_use_id:, content:, is_error: false, type: "tool_result")
+        super(type:, tool_use_id:, content:, is_error:)
+      end
+    end
+  end
+end
diff --git a/lib/dispatch/adapter/interface/model_info.rb b/lib/dispatch/adapter/interface/model_info.rb
new file mode 100644
index 0000000..8ba2977
--- /dev/null
+++ b/lib/dispatch/adapter/interface/model_info.rb
@@ -0,0 +1,17 @@
+# frozen_string_literal: true
+
+module Dispatch
+  module Adapter
+    ModelInfo = Struct.new(
+      :id, :name, :max_context_tokens,
+      :supports_vision, :supports_tool_use, :supports_streaming,
+      :premium_request_multiplier,
+      keyword_init: true
+    ) do
+      def initialize(id:, name:, max_context_tokens:, supports_vision:, supports_tool_use:, supports_streaming:,
+                     premium_request_multiplier: nil)
+        super
+      end
+    end
+  end
+end
diff --git a/lib/dispatch/adapter/interface/response.rb b/lib/dispatch/adapter/interface/response.rb
new file mode 100644
index 0000000..b4ba3eb
--- /dev/null
+++ b/lib/dispatch/adapter/interface/response.rb
@@ -0,0 +1,23 @@
+# frozen_string_literal: true
+
+module Dispatch
+  module Adapter
+    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)
+        super
+      end
+    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
+      end
+    end
+  end
+end
diff --git a/lib/dispatch/adapter/interface/tool_definition.rb b/lib/dispatch/adapter/interface/tool_definition.rb
new file mode 100644
index 0000000..7b435a3
--- /dev/null
+++ b/lib/dispatch/adapter/interface/tool_definition.rb
@@ -0,0 +1,7 @@
+# frozen_string_literal: true
+
+module Dispatch
+  module Adapter
+    ToolDefinition = Struct.new(:name, :description, :parameters, keyword_init: true)
+  end
+end
diff --git a/lib/dispatch/adapter/interface/version.rb b/lib/dispatch/adapter/interface/version.rb
new file mode 100644
index 0000000..0a53b34
--- /dev/null
+++ b/lib/dispatch/adapter/interface/version.rb
@@ -0,0 +1,9 @@
+# frozen_string_literal: true
+
+module Dispatch
+  module Adapter
+    module Interface
+      VERSION = "0.1.0"
+    end
+  end
+end