4 files changed, 354 insertions, 0 deletions
diff --git a/spec/dispatch/adapter/interface/base_spec.rb b/spec/dispatch/adapter/interface/base_spec.rb
new file mode 100644
index 0000000..8c3a279
--- /dev/null
+++ b/spec/dispatch/adapter/interface/base_spec.rb
@@ -0,0 +1,41 @@
+# frozen_string_literal: true
+
+RSpec.describe Dispatch::Adapter::Base do
+  subject(:base) { described_class.new }
+
+  describe "#chat" do
+    it "raises NotImplementedError" do
+      expect { base.chat([]) }.to raise_error(NotImplementedError, /chat must be implemented/)
+    end
+  end
+
+  describe "#model_name" do
+    it "raises NotImplementedError" do
+      expect { base.model_name }.to raise_error(NotImplementedError, /model_name must be implemented/)
+    end
+  end
+
+  describe "#count_tokens" do
+    it "returns -1" do
+      expect(base.count_tokens([])).to eq(-1)
+    end
+  end
+
+  describe "#list_models" do
+    it "raises NotImplementedError" do
+      expect { base.list_models }.to raise_error(NotImplementedError, /list_models must be implemented/)
+    end
+  end
+
+  describe "#provider_name" do
+    it "returns the class name" do
+      expect(base.provider_name).to eq("Dispatch::Adapter::Base")
+    end
+  end
+
+  describe "#max_context_tokens" do
+    it "returns nil" do
+      expect(base.max_context_tokens).to be_nil
+    end
+  end
+end
diff --git a/spec/dispatch/adapter/interface/errors_spec.rb b/spec/dispatch/adapter/interface/errors_spec.rb
new file mode 100644
index 0000000..906a4c2
--- /dev/null
+++ b/spec/dispatch/adapter/interface/errors_spec.rb
@@ -0,0 +1,69 @@
+# frozen_string_literal: true
+
+RSpec.describe Dispatch::Adapter::Error do
+  it "carries message, status_code, and provider" do
+    error = described_class.new("test error", status_code: 500, provider: "TestProvider")
+    expect(error.message).to eq("test error")
+    expect(error.status_code).to eq(500)
+    expect(error.provider).to eq("TestProvider")
+  end
+
+  it "defaults status_code and provider to nil" do
+    error = described_class.new("simple error")
+    expect(error.status_code).to be_nil
+    expect(error.provider).to be_nil
+  end
+
+  it "inherits from StandardError" do
+    expect(described_class.ancestors).to include(StandardError)
+  end
+
+  it "can be rescued as StandardError" do
+    expect do
+      raise described_class, "test"
+    end.to raise_error(StandardError)
+  end
+end
+
+RSpec.describe Dispatch::Adapter::AuthenticationError do
+  it "inherits from Error" do
+    expect(described_class.ancestors).to include(Dispatch::Adapter::Error)
+  end
+end
+
+RSpec.describe Dispatch::Adapter::RateLimitError do
+  it "carries retry_after" do
+    error = described_class.new("rate limited", status_code: 429, provider: "Test", retry_after: 30)
+    expect(error.retry_after).to eq(30)
+    expect(error.status_code).to eq(429)
+  end
+
+  it "defaults retry_after to nil" do
+    error = described_class.new("rate limited")
+    expect(error.retry_after).to be_nil
+  end
+
+  it "is rescuable as Dispatch::Adapter::Error" do
+    expect do
+      raise described_class, "rate limited"
+    end.to raise_error(Dispatch::Adapter::Error)
+  end
+end
+
+RSpec.describe Dispatch::Adapter::ServerError do
+  it "inherits from Error" do
+    expect(described_class.ancestors).to include(Dispatch::Adapter::Error)
+  end
+end
+
+RSpec.describe Dispatch::Adapter::RequestError do
+  it "inherits from Error" do
+    expect(described_class.ancestors).to include(Dispatch::Adapter::Error)
+  end
+end
+
+RSpec.describe Dispatch::Adapter::ConnectionError do
+  it "inherits from Error" do
+    expect(described_class.ancestors).to include(Dispatch::Adapter::Error)
+  end
+end
diff --git a/spec/dispatch/adapter/interface/structs_spec.rb b/spec/dispatch/adapter/interface/structs_spec.rb
new file mode 100644
index 0000000..ef8ec73
--- /dev/null
+++ b/spec/dispatch/adapter/interface/structs_spec.rb
@@ -0,0 +1,211 @@
+# frozen_string_literal: true
+
+RSpec.describe Dispatch::Adapter do
+  describe "Message" do
+    it "creates with keyword args" do
+      msg = Dispatch::Adapter::Message.new(role: "user", content: "Hello")
+      expect(msg.role).to eq("user")
+      expect(msg.content).to eq("Hello")
+    end
+
+    it "accepts array content" do
+      blocks = [Dispatch::Adapter::TextBlock.new(text: "hi")]
+      msg = Dispatch::Adapter::Message.new(role: "user", content: blocks)
+      expect(msg.content).to be_an(Array)
+      expect(msg.content.first.text).to eq("hi")
+    end
+  end
+
+  describe "TextBlock" do
+    it "defaults type to 'text'" do
+      block = Dispatch::Adapter::TextBlock.new(text: "hello")
+      expect(block.type).to eq("text")
+      expect(block.text).to eq("hello")
+    end
+  end
+
+  describe "ImageBlock" do
+    it "defaults type to 'image'" do
+      block = Dispatch::Adapter::ImageBlock.new(source: "data:image/png;base64,abc", media_type: "image/png")
+      expect(block.type).to eq("image")
+      expect(block.source).to eq("data:image/png;base64,abc")
+      expect(block.media_type).to eq("image/png")
+    end
+  end
+
+  describe "ToolUseBlock" do
+    it "defaults type to 'tool_use'" do
+      block = Dispatch::Adapter::ToolUseBlock.new(id: "call_1", name: "get_weather", arguments: { "city" => "NYC" })
+      expect(block.type).to eq("tool_use")
+      expect(block.id).to eq("call_1")
+      expect(block.name).to eq("get_weather")
+      expect(block.arguments).to eq({ "city" => "NYC" })
+    end
+  end
+
+  describe "ToolResultBlock" do
+    it "defaults type to 'tool_result' and is_error to false" do
+      block = Dispatch::Adapter::ToolResultBlock.new(tool_use_id: "call_1", content: "72F")
+      expect(block.type).to eq("tool_result")
+      expect(block.tool_use_id).to eq("call_1")
+      expect(block.content).to eq("72F")
+      expect(block.is_error).to be(false)
+    end
+
+    it "accepts is_error flag" do
+      block = Dispatch::Adapter::ToolResultBlock.new(tool_use_id: "call_1", content: "Error", is_error: true)
+      expect(block.is_error).to be(true)
+    end
+  end
+
+  describe "ToolDefinition" do
+    it "creates with keyword args" do
+      td = Dispatch::Adapter::ToolDefinition.new(
+        name: "search",
+        description: "Search the web",
+        parameters: { "type" => "object", "properties" => {} }
+      )
+      expect(td.name).to eq("search")
+      expect(td.description).to eq("Search the web")
+      expect(td.parameters).to be_a(Hash)
+    end
+  end
+
+  describe "Response" do
+    it "creates with defaults" do
+      usage = Dispatch::Adapter::Usage.new(input_tokens: 10, output_tokens: 20)
+      resp = Dispatch::Adapter::Response.new(model: "gpt-4", stop_reason: :end_turn, usage: usage)
+      expect(resp.content).to be_nil
+      expect(resp.tool_calls).to eq([])
+      expect(resp.model).to eq("gpt-4")
+      expect(resp.stop_reason).to eq(:end_turn)
+      expect(resp.usage).to eq(usage)
+    end
+
+    it "creates with all fields" do
+      usage = Dispatch::Adapter::Usage.new(input_tokens: 10, output_tokens: 20)
+      tool_call = Dispatch::Adapter::ToolUseBlock.new(id: "1", name: "test", arguments: {})
+      resp = Dispatch::Adapter::Response.new(
+        content: "Hello",
+        tool_calls: [tool_call],
+        model: "gpt-4",
+        stop_reason: :tool_use,
+        usage: usage
+      )
+      expect(resp.content).to eq("Hello")
+      expect(resp.tool_calls.size).to eq(1)
+    end
+  end
+
+  describe "Usage" do
+    it "defaults cache tokens to 0" do
+      usage = Dispatch::Adapter::Usage.new(input_tokens: 100, output_tokens: 50)
+      expect(usage.cache_read_tokens).to eq(0)
+      expect(usage.cache_creation_tokens).to eq(0)
+    end
+
+    it "accepts cache tokens" do
+      usage = Dispatch::Adapter::Usage.new(
+        input_tokens: 100,
+        output_tokens: 50,
+        cache_read_tokens: 10,
+        cache_creation_tokens: 5
+      )
+      expect(usage.cache_read_tokens).to eq(10)
+      expect(usage.cache_creation_tokens).to eq(5)
+    end
+  end
+
+  describe "StreamDelta" do
+    it "creates a text_delta" do
+      delta = Dispatch::Adapter::StreamDelta.new(type: :text_delta, text: "Hello")
+      expect(delta.type).to eq(:text_delta)
+      expect(delta.text).to eq("Hello")
+      expect(delta.tool_call_id).to be_nil
+    end
+
+    it "creates a tool_use_start" do
+      delta = Dispatch::Adapter::StreamDelta.new(type: :tool_use_start, tool_call_id: "1", tool_name: "search")
+      expect(delta.type).to eq(:tool_use_start)
+      expect(delta.tool_call_id).to eq("1")
+      expect(delta.tool_name).to eq("search")
+    end
+
+    it "creates a tool_use_delta" do
+      delta = Dispatch::Adapter::StreamDelta.new(type: :tool_use_delta, tool_call_id: "1", argument_delta: '{"q":')
+      expect(delta.type).to eq(:tool_use_delta)
+      expect(delta.argument_delta).to eq('{"q":')
+    end
+  end
+
+  describe "ModelInfo" do
+    it "creates with all fields" do
+      info = Dispatch::Adapter::ModelInfo.new(
+        id: "gpt-4",
+        name: "GPT-4",
+        max_context_tokens: 8192,
+        supports_vision: false,
+        supports_tool_use: true,
+        supports_streaming: true
+      )
+      expect(info.id).to eq("gpt-4")
+      expect(info.name).to eq("GPT-4")
+      expect(info.max_context_tokens).to eq(8192)
+      expect(info.supports_vision).to be(false)
+      expect(info.supports_tool_use).to be(true)
+      expect(info.supports_streaming).to be(true)
+      expect(info.premium_request_multiplier).to be_nil
+    end
+
+    it "accepts premium_request_multiplier" do
+      info = Dispatch::Adapter::ModelInfo.new(
+        id: "o3",
+        name: "o3",
+        max_context_tokens: 200_000,
+        supports_vision: false,
+        supports_tool_use: true,
+        supports_streaming: true,
+        premium_request_multiplier: 30.0
+      )
+      expect(info.premium_request_multiplier).to eq(30.0)
+    end
+
+    it "defaults premium_request_multiplier to nil" do
+      info = Dispatch::Adapter::ModelInfo.new(
+        id: "gpt-4.1-nano",
+        name: "GPT 4.1 Nano",
+        max_context_tokens: 1_047_576,
+        supports_vision: false,
+        supports_tool_use: true,
+        supports_streaming: true
+      )
+      expect(info.premium_request_multiplier).to be_nil
+    end
+  end
+
+  describe "Struct equality" do
+    it "considers structs with same values equal" do
+      a = Dispatch::Adapter::Message.new(role: "user", content: "hello")
+      b = Dispatch::Adapter::Message.new(role: "user", content: "hello")
+      expect(a).to eq(b)
+    end
+
+    it "considers structs with different values not equal" do
+      a = Dispatch::Adapter::Message.new(role: "user", content: "hello")
+      b = Dispatch::Adapter::Message.new(role: "user", content: "goodbye")
+      expect(a).not_to eq(b)
+    end
+
+    it "Usage structs are equal with same tokens" do
+      a = Dispatch::Adapter::Usage.new(input_tokens: 10, output_tokens: 20)
+      b = Dispatch::Adapter::Usage.new(input_tokens: 10, output_tokens: 20)
+      expect(a).to eq(b)
+    end
+
+    it "ToolUseBlock structs are equal with same fields" do
+      a = Dispatch::Adapter::ToolUseBlock.new(id: "1", name: "test", arguments: { "k" => "v" })
+      b = Dispatch::Adapter::ToolUseBlock.new(id: "1", name: "test", arguments: { "k" => "v" })
+      expect(a).to eq(b)
+    end
+  end
+end
diff --git a/spec/dispatch/adapter/interface_spec.rb b/spec/dispatch/adapter/interface_spec.rb
new file mode 100644
index 0000000..a62ed81
--- /dev/null
+++ b/spec/dispatch/adapter/interface_spec.rb
@@ -0,0 +1,33 @@
+# frozen_string_literal: true
+
+RSpec.describe Dispatch::Adapter::Interface do
+  it "has a version number" do
+    expect(Dispatch::Adapter::Interface::VERSION).not_to be_nil
+  end
+
+  it "exposes the Base class" do
+    expect(Dispatch::Adapter::Base).to be_a(Class)
+  end
+
+  it "exposes error classes" do
+    expect(Dispatch::Adapter::Error).to be < StandardError
+    expect(Dispatch::Adapter::AuthenticationError).to be < Dispatch::Adapter::Error
+    expect(Dispatch::Adapter::RateLimitError).to be < Dispatch::Adapter::Error
+    expect(Dispatch::Adapter::ServerError).to be < Dispatch::Adapter::Error
+    expect(Dispatch::Adapter::RequestError).to be < Dispatch::Adapter::Error
+    expect(Dispatch::Adapter::ConnectionError).to be < Dispatch::Adapter::Error
+  end
+
+  it "exposes data structs" do
+    expect(Dispatch::Adapter::Message).to be_a(Class)
+    expect(Dispatch::Adapter::TextBlock).to be_a(Class)
+    expect(Dispatch::Adapter::ImageBlock).to be_a(Class)
+    expect(Dispatch::Adapter::ToolUseBlock).to be_a(Class)
+    expect(Dispatch::Adapter::ToolResultBlock).to be_a(Class)
+    expect(Dispatch::Adapter::ToolDefinition).to be_a(Class)
+    expect(Dispatch::Adapter::Response).to be_a(Class)
+    expect(Dispatch::Adapter::Usage).to be_a(Class)
+    expect(Dispatch::Adapter::StreamDelta).to be_a(Class)
+    expect(Dispatch::Adapter::ModelInfo).to be_a(Class)
+  end
+end