From 55bf98f4b7f1907c6fa930f97ee13041b4a9fcf3 Mon Sep 17 00:00:00 2001
From: jameslong <846867+jameslong@users.noreply.github.com>
Date: Tue, 10 Jun 2025 16:27:58 -0700
Subject: [PATCH 01/12] Git ignore VSCode config file

---
 .gitignore | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/.gitignore b/.gitignore
index 9e94237..ee3776f 100644
--- a/.gitignore
+++ b/.gitignore
@@ -22,4 +22,7 @@ vancouver-*.tar
 # Temporary files, for example, from tests.
 /tmp/
 
-.DS_Store
\ No newline at end of file
+.DS_Store
+
+# VSCode config
+launch.json
\ No newline at end of file

From ab54c6305a685d1638353db30eef9ec642b8daac Mon Sep 17 00:00:00 2001
From: jameslong <846867+jameslong@users.noreply.github.com>
Date: Tue, 10 Jun 2025 19:35:01 -0700
Subject: [PATCH 02/12] Add ToolTest module

---
 lib/vancouver/test/tool_test.ex   | 110 ++++++++++++++++
 test/vancouver/test/tool_test.exs | 201 ++++++++++++++++++++++++++++++
 2 files changed, 311 insertions(+)
 create mode 100644 lib/vancouver/test/tool_test.ex
 create mode 100644 test/vancouver/test/tool_test.exs

diff --git a/lib/vancouver/test/tool_test.ex b/lib/vancouver/test/tool_test.ex
new file mode 100644
index 0000000..ce308b6
--- /dev/null
+++ b/lib/vancouver/test/tool_test.ex
@@ -0,0 +1,110 @@
+defmodule Vancouver.ToolTest do
+  @moduledoc """
+  Conveniences for testing Vancouver tools.
+  """
+
+  def call_request(tool_name, arguments, id \\ "1") do
+    %{
+      "jsonrpc" => "2.0",
+      "id" => id,
+      "method" => "tools/call",
+      "params" => %{
+        "name" => tool_name,
+        "arguments" => arguments
+      }
+    }
+  end
+
+  def audio_response(conn) do
+    response = JSON.decode!(conn.resp_body)
+
+    response
+    |> check_success()
+    |> check_type("audio")
+    |> get_content()
+  end
+
+  def error_response(conn) do
+    response = JSON.decode!(conn.resp_body)
+
+    response
+    |> check_error()
+    |> check_type("text")
+    |> get_text()
+  end
+
+  def image_response(conn) do
+    response = JSON.decode!(conn.resp_body)
+
+    response
+    |> check_success()
+    |> check_type("image")
+    |> get_content()
+  end
+
+  def json_response(conn) do
+    response = JSON.decode!(conn.resp_body)
+
+    response
+    |> check_success()
+    |> check_type("text")
+    |> get_json()
+  end
+
+  def text_response(conn) do
+    response = JSON.decode!(conn.resp_body)
+
+    response
+    |> check_success()
+    |> check_type("text")
+    |> get_text()
+  end
+
+  defp check_success(response) do
+    if error?(response) do
+      raise "expected success response, got: error"
+    else
+      response
+    end
+  end
+
+  defp check_error(response) do
+    if error?(response) do
+      response
+    else
+      raise "expected error response, got: success"
+    end
+  end
+
+  defp error?(response), do: response["result"]["isError"] || false
+
+  defp check_type(response, expected_type) do
+    type = get_content_type(response)
+
+    if expected_type == type do
+      response
+    else
+      raise "expected response with content type #{expected_type}, got: #{type}"
+    end
+  end
+
+  defp get_json(response) do
+    text = get_text(response)
+
+    case JSON.decode(get_text(response)) do
+      {:ok, json} -> json
+      {:error, _} -> raise "expected response content with valid JSON, got: #{text}"
+    end
+  end
+
+  defp get_text(response), do: get_content(response)["text"]
+
+  defp get_content(response) do
+    case response["result"]["content"] do
+      [content] -> content
+      content -> raise "expected response with single content item, got: #{inspect(content)}"
+    end
+  end
+
+  defp get_content_type(response), do: get_content(response)["type"]
+end
diff --git a/test/vancouver/test/tool_test.exs b/test/vancouver/test/tool_test.exs
new file mode 100644
index 0000000..d6cc84f
--- /dev/null
+++ b/test/vancouver/test/tool_test.exs
@@ -0,0 +1,201 @@
+defmodule Vancouver.Test.ToolTest do
+  use ExUnit.Case, async: true
+
+  import Plug.Conn
+  import Plug.Test
+
+  alias Vancouver.JsonRpc2
+  alias Vancouver.ToolTest
+
+  describe "call_request/3" do
+    test "creates a valid call request" do
+      tool_name = "test_tool"
+      arguments = %{"arg1" => "value1", "arg2" => "value2"}
+      id = "123"
+
+      assert ToolTest.call_request(tool_name, arguments, id) == %{
+               "jsonrpc" => "2.0",
+               "id" => id,
+               "method" => "tools/call",
+               "params" => %{
+                 "name" => tool_name,
+                 "arguments" => arguments
+               }
+             }
+    end
+  end
+
+  describe "audio_response/1" do
+    test "with valid conn returns content" do
+      content = [%{"type" => "audio", "data" => "base64-audio-data", "mimeType" => "audio/wav"}]
+      conn = build_success_conn(content)
+
+      response = ToolTest.audio_response(conn)
+      assert response["data"] == "base64-audio-data"
+      assert response["mimeType"] == "audio/wav"
+    end
+
+    test "with invalid conn raises error" do
+      assert_raise RuntimeError, "expected response with single content item, got: []", fn ->
+        content = []
+        conn = build_success_conn(content)
+        ToolTest.audio_response(conn)
+      end
+
+      assert_raise RuntimeError, "expected response with content type audio, got: text", fn ->
+        content = [%{"type" => "text", "text" => "text"}]
+        conn = build_success_conn(content)
+        ToolTest.audio_response(conn)
+      end
+
+      assert_raise RuntimeError, "expected success response, got: error", fn ->
+        content = [%{"type" => "text", "text" => "oops"}]
+        conn = build_error_conn(content)
+        ToolTest.audio_response(conn)
+      end
+    end
+  end
+
+  describe "error_response/1" do
+    test "with valid conn returns content" do
+      content = [%{"type" => "text", "text" => "oops"}]
+      conn = build_error_conn(content)
+
+      assert ToolTest.error_response(conn) == "oops"
+    end
+
+    test "with invalid conn raises error" do
+      assert_raise RuntimeError, "expected response with single content item, got: []", fn ->
+        content = []
+        conn = build_error_conn(content)
+        ToolTest.error_response(conn)
+      end
+
+      assert_raise RuntimeError, "expected response with content type text, got: image", fn ->
+        content = [%{"type" => "image", "data" => "base64-image-data", "mimeType" => "image/png"}]
+        conn = build_error_conn(content)
+        ToolTest.error_response(conn)
+      end
+
+      assert_raise RuntimeError, "expected error response, got: success", fn ->
+        content = [%{"type" => "text", "text" => "Hello, world!"}]
+        conn = build_success_conn(content)
+        ToolTest.error_response(conn)
+      end
+    end
+  end
+
+  describe "image_response/1" do
+    test "with valid conn returns content" do
+      content = [%{"type" => "image", "data" => "base64-image-data", "mimeType" => "image/png"}]
+      conn = build_success_conn(content)
+
+      response = ToolTest.image_response(conn)
+      assert response["data"] == "base64-image-data"
+      assert response["mimeType"] == "image/png"
+    end
+
+    test "with invalid conn raises error" do
+      assert_raise RuntimeError, "expected response with single content item, got: []", fn ->
+        content = []
+        conn = build_success_conn(content)
+        ToolTest.image_response(conn)
+      end
+
+      assert_raise RuntimeError, "expected response with content type image, got: text", fn ->
+        content = [%{"type" => "text", "text" => "Hello, world!"}]
+        conn = build_success_conn(content)
+        ToolTest.image_response(conn)
+      end
+
+      assert_raise RuntimeError, "expected success response, got: error", fn ->
+        content = [%{"type" => "text", "text" => "oops"}]
+        conn = build_error_conn(content)
+        ToolTest.image_response(conn)
+      end
+    end
+  end
+
+  describe "json_response/1" do
+    test "with valid conn returns content" do
+      content = [%{"type" => "text", "text" => "{\"key\": \"value\"}"}]
+      conn = build_success_conn(content)
+
+      assert %{"key" => "value"} = ToolTest.json_response(conn)
+    end
+
+    test "with invalid conn raises error" do
+      assert_raise RuntimeError, "expected response with single content item, got: []", fn ->
+        content = []
+        conn = build_success_conn(content)
+        ToolTest.json_response(conn)
+      end
+
+      assert_raise RuntimeError, "expected response with content type text, got: image", fn ->
+        content = [%{"type" => "image", "data" => "base64-image-data", "mimeType" => "image/png"}]
+        conn = build_success_conn(content)
+        ToolTest.json_response(conn)
+      end
+
+      assert_raise RuntimeError, "expected response content with valid JSON, got: %{}", fn ->
+        content = [%{"type" => "text", "text" => "%{}"}]
+        conn = build_success_conn(content)
+        ToolTest.json_response(conn)
+      end
+
+      assert_raise RuntimeError, "expected success response, got: error", fn ->
+        content = [%{"type" => "text", "text" => "oops"}]
+        conn = build_error_conn(content)
+        ToolTest.json_response(conn)
+      end
+    end
+  end
+
+  describe "text_response/1" do
+    test "with valid conn returns content" do
+      text = "Hello, world!"
+      content = [%{"type" => "text", "text" => text}]
+      conn = build_success_conn(content)
+
+      assert ToolTest.text_response(conn) == text
+    end
+
+    test "with invalid conn raises error" do
+      assert_raise RuntimeError, "expected response with single content item, got: []", fn ->
+        content = []
+        conn = build_success_conn(content)
+        ToolTest.text_response(conn)
+      end
+
+      assert_raise RuntimeError, "expected response with content type text, got: image", fn ->
+        content = [%{"type" => "image", "data" => "base64-image-data", "mimeType" => "image/png"}]
+        conn = build_success_conn(content)
+        ToolTest.text_response(conn)
+      end
+
+      assert_raise RuntimeError, "expected success response, got: error", fn ->
+        content = [%{"type" => "text", "text" => "oops"}]
+        conn = build_error_conn(content)
+        ToolTest.text_response(conn)
+      end
+    end
+  end
+
+  defp build_success_conn(content, request_id \\ 1) do
+    build_response_conn(content, request_id, false)
+  end
+
+  defp build_error_conn(content, request_id \\ 1) do
+    build_response_conn(content, request_id, true)
+  end
+
+  def build_response_conn(content, request_id \\ 1, is_error \\ false) do
+    result = %{"content" => content, "isError" => is_error}
+    body = JsonRpc2.success_response(request_id, result)
+
+    conn(:post, "/")
+    |> put_req_header("content-type", "application/json")
+    |> Map.put(:resp_body, JSON.encode!(body))
+    |> put_status(200)
+  end
+end

From 6d8db73b0f2a3cc0df77ffcf4983f54b2b412967 Mon Sep 17 00:00:00 2001
From: jameslong <846867+jameslong@users.noreply.github.com>
Date: Tue, 10 Jun 2025 19:44:26 -0700
Subject: [PATCH 03/12] Add typespecs for ToolTest module

---
 lib/vancouver/test/tool_test.ex | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/lib/vancouver/test/tool_test.ex b/lib/vancouver/test/tool_test.ex
index ce308b6..4dc68d7 100644
--- a/lib/vancouver/test/tool_test.ex
+++ b/lib/vancouver/test/tool_test.ex
@@ -3,6 +3,7 @@ defmodule Vancouver.ToolTest do
   Conveniences for testing Vancouver tools.
   """
 
+  @spec call_request(String.t(), map(), String.t()) :: map()
   def call_request(tool_name, arguments, id \\ "1") do
     %{
       "jsonrpc" => "2.0",
@@ -15,6 +16,7 @@ defmodule Vancouver.ToolTest do
     }
   end
 
+  @spec audio_response(Plug.Conn.t()) :: %{data: String.t(), mimeType: String.t()}
   def audio_response(conn) do
     response = JSON.decode!(conn.resp_body)
 
@@ -24,6 +26,7 @@ defmodule Vancouver.ToolTest do
     |> get_content()
   end
 
+  @spec error_response(Plug.Conn.t()) :: String.t()
   def error_response(conn) do
     response = JSON.decode!(conn.resp_body)
 
@@ -33,6 +36,7 @@ defmodule Vancouver.ToolTest do
     |> get_text()
   end
 
+  @spec image_response(Plug.Conn.t()) :: %{data: String.t(), mimeType: String.t()}
   def image_response(conn) do
     response = JSON.decode!(conn.resp_body)
 
@@ -42,6 +46,7 @@ defmodule Vancouver.ToolTest do
     |> get_content()
   end
 
+  @spec json_response(Plug.Conn.t()) :: term()
   def json_response(conn) do
     response = JSON.decode!(conn.resp_body)
 
@@ -51,6 +56,7 @@ defmodule Vancouver.ToolTest do
     |> get_json()
   end
 
+  @spec text_response(Plug.Conn.t()) :: String.t()
   def text_response(conn) do
     response = JSON.decode!(conn.resp_body)
 

From 07ef71c490a224cdd9c40d7a19520a5277afb8b1 Mon Sep 17 00:00:00 2001
From: jameslong <846867+jameslong@users.noreply.github.com>
Date: Tue, 10 Jun 2025 19:52:35 -0700
Subject: [PATCH 04/12] Add function docs to ToolTest module

---
 lib/vancouver/test/tool_test.ex | 52 +++++++++++++++++++++++++++++++++
 1 file changed, 52 insertions(+)

diff --git a/lib/vancouver/test/tool_test.ex b/lib/vancouver/test/tool_test.ex
index 4dc68d7..ac51108 100644
--- a/lib/vancouver/test/tool_test.ex
+++ b/lib/vancouver/test/tool_test.ex
@@ -3,6 +3,14 @@ defmodule Vancouver.ToolTest do
   Conveniences for testing Vancouver tools.
   """
 
+  @doc """
+  Creates a JSON-RPC call request for a tool.
+
+  ## Examples
+
+      body = call_request("calculate_sum", %{"a" => 1, "b" => 2})
+
+  """
   @spec call_request(String.t(), map(), String.t()) :: map()
   def call_request(tool_name, arguments, id \\ "1") do
     %{
@@ -16,6 +24,16 @@ defmodule Vancouver.ToolTest do
     }
   end
 
+  @doc """
+  Asserts that the response was successful, and that audio content was returned.
+
+  ## Examples
+
+      content = audio_response(conn)
+      assert content["data"] == "base64-audio-data"
+      assert content["mimeType"] == "audio/wav"
+
+  """
   @spec audio_response(Plug.Conn.t()) :: %{data: String.t(), mimeType: String.t()}
   def audio_response(conn) do
     response = JSON.decode!(conn.resp_body)
@@ -26,6 +44,14 @@ defmodule Vancouver.ToolTest do
     |> get_content()
   end
 
+  @doc """
+  Asserts that the response was an error, and returns the error text.
+
+  ## Examples
+
+      assert error_response(conn) == "An error occurred"
+
+  """
   @spec error_response(Plug.Conn.t()) :: String.t()
   def error_response(conn) do
     response = JSON.decode!(conn.resp_body)
@@ -36,6 +62,16 @@ defmodule Vancouver.ToolTest do
     |> get_text()
   end
 
+  @doc """
+  Asserts that the response was successful, and that image content was returned.
+
+  ## Examples
+
+      content = image_response(conn)
+      assert content["data"] == "base64-image-data"
+      assert content["mimeType"] == "image/png"
+
+  """
   @spec image_response(Plug.Conn.t()) :: %{data: String.t(), mimeType: String.t()}
   def image_response(conn) do
     response = JSON.decode!(conn.resp_body)
@@ -46,6 +82,14 @@ defmodule Vancouver.ToolTest do
     |> get_content()
   end
 
+  @doc """
+  Asserts that the response was successful, and that JSON content was returned.
+
+  ## Examples
+
+      assert json_response(conn) == %{"key" => "value"}
+
+  """
   @spec json_response(Plug.Conn.t()) :: term()
   def json_response(conn) do
     response = JSON.decode!(conn.resp_body)
@@ -56,6 +100,14 @@ defmodule Vancouver.ToolTest do
     |> get_json()
   end
 
+  @doc """
+  Asserts that the response was successful, and that text content was returned.
+
+  ## Examples
+
+      assert text_response(conn) == "Hello, world!"
+
+  """
   @spec text_response(Plug.Conn.t()) :: String.t()
   def text_response(conn) do
     response = JSON.decode!(conn.resp_body)

From eaf0c5ef7988397d3ac0ae38cc086d54d52a9a9e Mon Sep 17 00:00:00 2001
From: jameslong <846867+jameslong@users.noreply.github.com>
Date: Tue, 10 Jun 2025 19:55:34 -0700
Subject: [PATCH 05/12] Remove id argument (not required for now)

---
 lib/vancouver/test/tool_test.ex   | 8 ++++----
 test/vancouver/test/tool_test.exs | 5 ++---
 2 files changed, 6 insertions(+), 7 deletions(-)

diff --git a/lib/vancouver/test/tool_test.ex b/lib/vancouver/test/tool_test.ex
index ac51108..bd83a32 100644
--- a/lib/vancouver/test/tool_test.ex
+++ b/lib/vancouver/test/tool_test.ex
@@ -4,18 +4,18 @@ defmodule Vancouver.ToolTest do
   """
 
   @doc """
-  Creates a JSON-RPC call request for a tool.
+  Creates a valid request body for a tool call request.
 
   ## Examples
 
       body = call_request("calculate_sum", %{"a" => 1, "b" => 2})
 
   """
-  @spec call_request(String.t(), map(), String.t()) :: map()
-  def call_request(tool_name, arguments, id \\ "1") do
+  @spec call_request(String.t(), map()) :: map()
+  def call_request(tool_name, arguments) do
     %{
       "jsonrpc" => "2.0",
-      "id" => id,
+      "id" => 1,
       "method" => "tools/call",
       "params" => %{
         "name" => tool_name,
diff --git a/test/vancouver/test/tool_test.exs b/test/vancouver/test/tool_test.exs
index d6cc84f..11cb243 100644
--- a/test/vancouver/test/tool_test.exs
+++ b/test/vancouver/test/tool_test.exs
@@ -11,11 +11,10 @@ defmodule Vancouver.Test.ToolTest do
     test "creates a valid call request" do
       tool_name = "test_tool"
       arguments = %{"arg1" => "value1", "arg2" => "value2"}
-      id = "123"
 
-      assert ToolTest.call_request(tool_name, arguments, id) == %{
+      assert ToolTest.call_request(tool_name, arguments) == %{
                "jsonrpc" => "2.0",
-               "id" => id,
+               "id" => 1,
                "method" => "tools/call",
                "params" => %{
                  "name" => tool_name,

From 47a197921b008a2d32882b8d66a82850ad73857c Mon Sep 17 00:00:00 2001
From: jameslong <846867+jameslong@users.noreply.github.com>
Date: Wed, 11 Jun 2025 08:44:44 -0700
Subject: [PATCH 06/12] Use string keys for json rpc messages

---
 lib/vancouver/tool.ex | 36 ++++++++++++++++++------------------
 1 file changed, 18 insertions(+), 18 deletions(-)

diff --git a/lib/vancouver/tool.ex b/lib/vancouver/tool.ex
index add350e..2ccd4db 100644
--- a/lib/vancouver/tool.ex
+++ b/lib/vancouver/tool.ex
@@ -91,14 +91,14 @@ defmodule Vancouver.Tool do
   def send_audio(%Plug.Conn{} = conn, base64_data, mime_type)
       when is_binary(base64_data) and is_binary(mime_type) do
     result = %{
-      content: [
+      "content" => [
         %{
-          type: "audio",
-          data: base64_data,
-          mimeType: mime_type
+          "type" => "audio",
+          "data" => base64_data,
+          "mimeType" => mime_type
         }
       ],
-      isError: false
+      "isError" => false
     }
 
     send_success(conn, result)
@@ -115,13 +115,13 @@ defmodule Vancouver.Tool do
   @spec send_error(Plug.Conn.t(), binary()) :: Plug.Conn.t()
   def send_error(%Plug.Conn{} = conn, message) do
     result = %{
-      content: [
+      "content" => [
         %{
-          type: "text",
-          text: message
+          "type" => "text",
+          "text" => message
         }
       ],
-      isError: true
+      "isError" => true
     }
 
     send_success(conn, result)
@@ -139,14 +139,14 @@ defmodule Vancouver.Tool do
   def send_image(%Plug.Conn{} = conn, base64_data, mime_type)
       when is_binary(base64_data) and is_binary(mime_type) do
     result = %{
-      content: [
+      "content" => [
         %{
-          type: "image",
-          data: base64_data,
-          mimeType: mime_type
+          "type" => "image",
+          "data" => base64_data,
+          "mimeType" => mime_type
         }
       ],
-      isError: false
+      "isError" => false
     }
 
     send_success(conn, result)
@@ -174,13 +174,13 @@ defmodule Vancouver.Tool do
   @spec send_text(Plug.Conn.t(), binary()) :: Plug.Conn.t()
   def send_text(%Plug.Conn{} = conn, text) when is_binary(text) do
     result = %{
-      content: [
+      "content" => [
         %{
-          type: "text",
-          text: text
+          "type" => "text",
+          "text" => text
         }
       ],
-      isError: false
+      "isError" => false
     }
 
     send_success(conn, result)

From a464128814266dc51ba42251ea503ed72364ca06 Mon Sep 17 00:00:00 2001
From: jameslong <846867+jameslong@users.noreply.github.com>
Date: Wed, 11 Jun 2025 09:07:42 -0700
Subject: [PATCH 07/12] Add tests for CalculateSum tool

---
 test/vancouver/tools/calculate_sum_test.exs | 30 +++++++++++++++++++++
 1 file changed, 30 insertions(+)
 create mode 100644 test/vancouver/tools/calculate_sum_test.exs

diff --git a/test/vancouver/tools/calculate_sum_test.exs b/test/vancouver/tools/calculate_sum_test.exs
new file mode 100644
index 0000000..98e1525
--- /dev/null
+++ b/test/vancouver/tools/calculate_sum_test.exs
@@ -0,0 +1,30 @@
+defmodule Vancouver.Tools.CalculateSumTest do
+  use ExUnit.Case, async: false
+
+  import Plug.Conn
+  import Plug.Test
+
+  alias Vancouver.Tools.CalculateSum
+  alias Vancouver.ToolTest
+
+  describe "run/2" do
+    setup do
+      Application.put_env(:vancouver, :tools, [CalculateSum])
+      :ok
+    end
+
+    test "with argunments returns success" do
+      conn = build_conn("calculate_sum", %{"a" => 1, "b" => 2})
+      assert ToolTest.text_response(conn) == "3"
+    end
+  end
+
+  defp build_conn(tool_name, tool_arguments) do
+    body = ToolTest.call_request(tool_name, tool_arguments)
+
+    :post
+    |> conn("/", JSON.encode!(body))
+    |> put_req_header("content-type", "application/json")
+    |> Vancouver.Router.call(Vancouver.Router.init([]))
+  end
+end

From ff0e0eb326aed9e5f213cb8870e48606471f6ee6 Mon Sep 17 00:00:00 2001
From: jameslong <846867+jameslong@users.noreply.github.com>
Date: Wed, 11 Jun 2025 09:08:18 -0700
Subject: [PATCH 08/12] Add TestResponse tool

Used to test all response helpers.
---
 lib/vancouver/tools/test_response.ex        | 41 +++++++++++++++
 test/vancouver/tools/test_response_test.exs | 56 +++++++++++++++++++++
 2 files changed, 97 insertions(+)
 create mode 100644 lib/vancouver/tools/test_response.ex
 create mode 100644 test/vancouver/tools/test_response_test.exs

diff --git a/lib/vancouver/tools/test_response.ex b/lib/vancouver/tools/test_response.ex
new file mode 100644
index 0000000..5227f31
--- /dev/null
+++ b/lib/vancouver/tools/test_response.ex
@@ -0,0 +1,41 @@
+defmodule Vancouver.Tools.TestResponse do
+  @moduledoc false
+
+  use Vancouver.Tool
+
+  def name, do: "test_response"
+  def description, do: "Returns success/error responses for all context types"
+
+  def input_schema do
+    %{
+      "type" => "object",
+      "properties" => %{
+        "response_type" => %{
+          "type" => "string",
+          "enum" => ["audio", "error", "image", "json", "text"]
+        }
+      },
+      "required" => ["response_type"]
+    }
+  end
+
+  def run(conn, %{"response_type" => "audio"}) do
+    send_audio(conn, "base64-encoded-audio-data", "audio/wav")
+  end
+
+  def run(conn, %{"response_type" => "error"}) do
+    send_error(conn, "Error message")
+  end
+
+  def run(conn, %{"response_type" => "image"}) do
+    send_image(conn, "base64-encoded-data", "image/png")
+  end
+
+  def run(conn, %{"response_type" => "json"}) do
+    send_json(conn, %{"key" => "value"})
+  end
+
+  def run(conn, %{"response_type" => "text"}) do
+    send_text(conn, "Success text")
+  end
+end
diff --git a/test/vancouver/tools/test_response_test.exs b/test/vancouver/tools/test_response_test.exs
new file mode 100644
index 0000000..2e910c6
--- /dev/null
+++ b/test/vancouver/tools/test_response_test.exs
@@ -0,0 +1,56 @@
+defmodule Vancouver.Tools.TestResponseTest do
+  use ExUnit.Case, async: false
+
+  import Plug.Conn
+  import Plug.Test
+
+  alias Vancouver.Tools.TestResponse
+  alias Vancouver.ToolTest
+
+  describe "run/2" do
+    setup do
+      Application.put_env(:vancouver, :tools, [TestResponse])
+      :ok
+    end
+
+    test "with audio response type returns success" do
+      conn = build_conn("test_response", %{"response_type" => "audio"})
+
+      audio = ToolTest.audio_response(conn)
+      assert audio["data"] == "base64-encoded-audio-data"
+      assert audio["mimeType"] == "audio/wav"
+    end
+
+    test "with error response type returns error" do
+      conn = build_conn("test_response", %{"response_type" => "error"})
+      assert ToolTest.error_response(conn) == "Error message"
+    end
+
+    test "with image response type returns success" do
+      conn = build_conn("test_response", %{"response_type" => "image"})
+
+      image = ToolTest.image_response(conn)
+      assert image["data"] == "base64-encoded-data"
+      assert image["mimeType"] == "image/png"
+    end
+
+    test "with json response type returns success" do
+      conn = build_conn("test_response", %{"response_type" => "json"})
+      assert ToolTest.json_response(conn) == %{"key" => "value"}
+    end
+
+    test "with text response type returns success" do
+      conn = build_conn("test_response", %{"response_type" => "text"})
+      assert ToolTest.text_response(conn) == "Success text"
+    end
+  end
+
+  defp build_conn(tool_name, tool_arguments) do
+    body = ToolTest.call_request(tool_name, tool_arguments)
+
+    :post
+    |> conn("/", JSON.encode!(body))
+    |> put_req_header("content-type", "application/json")
+    |> Vancouver.Router.call(Vancouver.Router.init([]))
+  end
+end

From 954cababce959a557b8dc3e7904ada009051fd8d Mon Sep 17 00:00:00 2001
From: jameslong <846867+jameslong@users.noreply.github.com>
Date: Wed, 11 Jun 2025 10:45:12 -0700
Subject: [PATCH 09/12] Remove tools from global config

This allows for simpler, concurrent testing.
---
 lib/vancouver/plugs/dispatch.ex             |  2 +-
 lib/vancouver/plugs/pipeline.ex             |  3 ++-
 lib/vancouver/router.ex                     |  8 +-------
 test/vancouver/tools/calculate_sum_test.exs | 10 +++-------
 test/vancouver/tools/test_response_test.exs | 10 +++-------
 5 files changed, 10 insertions(+), 23 deletions(-)

diff --git a/lib/vancouver/plugs/dispatch.ex b/lib/vancouver/plugs/dispatch.ex
index 73c7fe7..cc94f95 100644
--- a/lib/vancouver/plugs/dispatch.ex
+++ b/lib/vancouver/plugs/dispatch.ex
@@ -8,7 +8,7 @@ defmodule Vancouver.Plugs.Dispatch do
   def call(%Plug.Conn{} = conn, _opts) do
     request = conn.body_params
     method = request["method"]
-    tools = Application.get_env(:vancouver, :tools, [])
+    tools = conn.assigns[:vancouver][:tools] || []
 
     case method do
       "initialize" -> Methods.Initialize.run(conn)
diff --git a/lib/vancouver/plugs/pipeline.ex b/lib/vancouver/plugs/pipeline.ex
index da78f69..0bba6c6 100644
--- a/lib/vancouver/plugs/pipeline.ex
+++ b/lib/vancouver/plugs/pipeline.ex
@@ -1,7 +1,8 @@
 defmodule Vancouver.Plugs.Pipeline do
   @moduledoc false
 
-  use Plug.Builder
+  use Plug.Builder, copy_opts_to_assign: :vancouver
+
   alias Vancouver.Plugs
 
   plug(Plug.Parsers, parsers: [:json], pass: ["application/json"], json_decoder: JSON)
diff --git a/lib/vancouver/router.ex b/lib/vancouver/router.ex
index 7097a6a..38de845 100644
--- a/lib/vancouver/router.ex
+++ b/lib/vancouver/router.ex
@@ -8,11 +8,5 @@ defmodule Vancouver.Router do
   plug(:match)
   plug(:dispatch)
 
-  post "/" do
-    Pipeline.call(conn, Pipeline.init([]))
-  end
-
-  match _ do
-    send_resp(conn, 404, "Not found")
-  end
+  forward("/", to: Pipeline)
 end
diff --git a/test/vancouver/tools/calculate_sum_test.exs b/test/vancouver/tools/calculate_sum_test.exs
index 98e1525..d20c16b 100644
--- a/test/vancouver/tools/calculate_sum_test.exs
+++ b/test/vancouver/tools/calculate_sum_test.exs
@@ -1,18 +1,14 @@
 defmodule Vancouver.Tools.CalculateSumTest do
-  use ExUnit.Case, async: false
+  use ExUnit.Case, async: true
 
   import Plug.Conn
   import Plug.Test
 
+  alias Vancouver.Plugs.Pipeline
   alias Vancouver.Tools.CalculateSum
   alias Vancouver.ToolTest
 
   describe "run/2" do
-    setup do
-      Application.put_env(:vancouver, :tools, [CalculateSum])
-      :ok
-    end
-
     test "with argunments returns success" do
       conn = build_conn("calculate_sum", %{"a" => 1, "b" => 2})
       assert ToolTest.text_response(conn) == "3"
@@ -25,6 +21,6 @@ defmodule Vancouver.Tools.CalculateSumTest do
     :post
     |> conn("/", JSON.encode!(body))
     |> put_req_header("content-type", "application/json")
-    |> Vancouver.Router.call(Vancouver.Router.init([]))
+    |> Pipeline.call(tools: [CalculateSum])
   end
 end
diff --git a/test/vancouver/tools/test_response_test.exs b/test/vancouver/tools/test_response_test.exs
index 2e910c6..1d9566a 100644
--- a/test/vancouver/tools/test_response_test.exs
+++ b/test/vancouver/tools/test_response_test.exs
@@ -1,18 +1,14 @@
 defmodule Vancouver.Tools.TestResponseTest do
-  use ExUnit.Case, async: false
+  use ExUnit.Case, async: true
 
   import Plug.Conn
   import Plug.Test
 
+  alias Vancouver.Plugs.Pipeline
   alias Vancouver.Tools.TestResponse
   alias Vancouver.ToolTest
 
   describe "run/2" do
-    setup do
-      Application.put_env(:vancouver, :tools, [TestResponse])
-      :ok
-    end
-
     test "with audio response type returns success" do
       conn = build_conn("test_response", %{"response_type" => "audio"})
 
@@ -51,6 +47,6 @@ defmodule Vancouver.Tools.TestResponseTest do
     :post
     |> conn("/", JSON.encode!(body))
     |> put_req_header("content-type", "application/json")
-    |> Vancouver.Router.call(Vancouver.Router.init([]))
+    |> Pipeline.call(tools: [TestResponse])
   end
 end

From 30b63b58860d39bdbccfd2b24fe301a317a5767e Mon Sep 17 00:00:00 2001
From: jameslong <846867+jameslong@users.noreply.github.com>
Date: Wed, 11 Jun 2025 13:13:55 -0700
Subject: [PATCH 10/12] Set assigns at router level

---
 lib/vancouver/plugs/pipeline.ex             | 2 +-
 lib/vancouver/router.ex                     | 5 +++--
 test/vancouver/tools/calculate_sum_test.exs | 4 ++--
 test/vancouver/tools/test_response_test.exs | 4 ++--
 4 files changed, 8 insertions(+), 7 deletions(-)

diff --git a/lib/vancouver/plugs/pipeline.ex b/lib/vancouver/plugs/pipeline.ex
index 0bba6c6..cab50aa 100644
--- a/lib/vancouver/plugs/pipeline.ex
+++ b/lib/vancouver/plugs/pipeline.ex
@@ -1,7 +1,7 @@
 defmodule Vancouver.Plugs.Pipeline do
   @moduledoc false
 
-  use Plug.Builder, copy_opts_to_assign: :vancouver
+  use Plug.Builder
 
   alias Vancouver.Plugs
 
diff --git a/lib/vancouver/router.ex b/lib/vancouver/router.ex
index 38de845..c6a760b 100644
--- a/lib/vancouver/router.ex
+++ b/lib/vancouver/router.ex
@@ -1,12 +1,13 @@
 defmodule Vancouver.Router do
   @moduledoc false
 
-  use Plug.Router
+  use Plug.Router, copy_opts_to_assign: :vancouver
 
   alias Vancouver.Plugs.Pipeline
 
   plug(:match)
   plug(:dispatch)
 
-  forward("/", to: Pipeline)
+  post("/", do: Pipeline.call(conn, Pipeline.init([])))
+  match(_, do: send_resp(conn, 404, "Not found"))
 end
diff --git a/test/vancouver/tools/calculate_sum_test.exs b/test/vancouver/tools/calculate_sum_test.exs
index d20c16b..30a84ee 100644
--- a/test/vancouver/tools/calculate_sum_test.exs
+++ b/test/vancouver/tools/calculate_sum_test.exs
@@ -4,7 +4,7 @@ defmodule Vancouver.Tools.CalculateSumTest do
   import Plug.Conn
   import Plug.Test
 
-  alias Vancouver.Plugs.Pipeline
+  alias Vancouver.Router
   alias Vancouver.Tools.CalculateSum
   alias Vancouver.ToolTest
 
@@ -21,6 +21,6 @@ defmodule Vancouver.Tools.CalculateSumTest do
     :post
     |> conn("/", JSON.encode!(body))
     |> put_req_header("content-type", "application/json")
-    |> Pipeline.call(tools: [CalculateSum])
+    |> Router.call(tools: [CalculateSum])
   end
 end
diff --git a/test/vancouver/tools/test_response_test.exs b/test/vancouver/tools/test_response_test.exs
index 1d9566a..a0f85ec 100644
--- a/test/vancouver/tools/test_response_test.exs
+++ b/test/vancouver/tools/test_response_test.exs
@@ -4,7 +4,7 @@ defmodule Vancouver.Tools.TestResponseTest do
   import Plug.Conn
   import Plug.Test
 
-  alias Vancouver.Plugs.Pipeline
+  alias Vancouver.Router
   alias Vancouver.Tools.TestResponse
   alias Vancouver.ToolTest
 
@@ -47,6 +47,6 @@ defmodule Vancouver.Tools.TestResponseTest do
     :post
     |> conn("/", JSON.encode!(body))
     |> put_req_header("content-type", "application/json")
-    |> Pipeline.call(tools: [TestResponse])
+    |> Router.call(tools: [TestResponse])
   end
 end

From 277c039e342221ce89a57a6202411a860b07b69e Mon Sep 17 00:00:00 2001
From: jameslong <846867+jameslong@users.noreply.github.com>
Date: Wed, 11 Jun 2025 13:59:45 -0700
Subject: [PATCH 11/12] Update README with new tool option

---
 README.md | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/README.md b/README.md
index 05c286d..b435df8 100644
--- a/README.md
+++ b/README.md
@@ -49,10 +49,7 @@ In `config.ex`:
 ```elixir
 config :vancouver,
   name: "My MCP Server",
-  version: "1.0.0",
-  tools: [
-    MyApp.Tools.CalculateSum
-  ]
+  version: "1.0.0"
 ```
 
 ### 4. Add your MCP route
@@ -60,7 +57,7 @@ config :vancouver,
 In `router.ex`:
 
 ```elixir
-forward "/mcp", Vancouver.Router
+forward "/mcp", Vancouver.Router, tools: [MyApp.Tools.CalculateSum]
 ```
 
 ### 5. (Optional) Add to your MCP client

From 55072afc7b7bd4d77aeb2939741f47635bf8aee0 Mon Sep 17 00:00:00 2001
From: James Long <846867+jameslong@users.noreply.github.com>
Date: Wed, 11 Jun 2025 14:29:19 -0700
Subject: [PATCH 12/12] Update test/vancouver/tools/calculate_sum_test.exs

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
---
 test/vancouver/tools/calculate_sum_test.exs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/vancouver/tools/calculate_sum_test.exs b/test/vancouver/tools/calculate_sum_test.exs
index 30a84ee..2013f87 100644
--- a/test/vancouver/tools/calculate_sum_test.exs
+++ b/test/vancouver/tools/calculate_sum_test.exs
@@ -9,7 +9,7 @@ defmodule Vancouver.Tools.CalculateSumTest do
   alias Vancouver.ToolTest
 
   describe "run/2" do
-    test "with argunments returns success" do
+    test "with arguments returns success" do
       conn = build_conn("calculate_sum", %{"a" => 1, "b" => 2})
       assert ToolTest.text_response(conn) == "3"
     end