diff --git a/enterprise/app/helpers/captain/chat_helper.rb b/enterprise/app/helpers/captain/chat_helper.rb
index 390ec6cf8..ad119c413 100644
--- a/enterprise/app/helpers/captain/chat_helper.rb
+++ b/enterprise/app/helpers/captain/chat_helper.rb
@@ -2,12 +2,11 @@ module Captain::ChatHelper
   def request_chat_completion
     Rails.logger.debug { "[CAPTAIN][ChatCompletion] #{@messages}" }
 
-    available_tools = @tool_registry&.registered_tools || []
     response = @client.chat(
       parameters: {
         model: @model,
         messages: @messages,
-        tools: available_tools,
+        tools: @tool_registry&.registered_tools || [],
         response_format: { type: 'json_object' }
       }
     )
@@ -37,17 +36,24 @@ module Captain::ChatHelper
   end
 
   def process_tool_call(tool_call)
+    arguments = JSON.parse(tool_call['function']['arguments'])
+    function_name = tool_call['function']['name']
     tool_call_id = tool_call['id']
     function_name = tool_call['function']['name']
     arguments = JSON.parse(tool_call['function']['arguments'])
 
     if @tool_registry.respond_to?(function_name)
-      execute_tool_call(tool_call_id, function_name, arguments)
+      execute_tool(function_name, arguments, tool_call_id)
     else
       process_invalid_tool_call(tool_call_id, function_name)
     end
   end
 
+  def execute_tool(function_name, arguments, tool_call_id)
+    result = @tool_registry.send(function_name, arguments)
+    append_tool_response(result, tool_call_id)
+  end
+
   def append_tool_calls(tool_calls)
     @messages << {
       role: 'assistant',
diff --git a/enterprise/app/services/captain/copilot/chat_service.rb b/enterprise/app/services/captain/copilot/chat_service.rb
index bec0682e9..8d9009f01 100644
--- a/enterprise/app/services/captain/copilot/chat_service.rb
+++ b/enterprise/app/services/captain/copilot/chat_service.rb
@@ -61,6 +61,11 @@ class Captain::Copilot::ChatService < Llm::BaseOpenAiService
 
   private
 
+  def register_tools
+    @tool_registry = Captain::ToolRegistryService.new(@assistant)
+    @tool_registry.register_tool(Captain::Tools::SearchDocumentationService)
+  end
+
   def system_message
     Rails.logger.info("[CAPTAIN][CopilotChatService] Generating system message for product=#{@assistant.config['product_name']} language=#{@language}")
     {
diff --git a/enterprise/app/services/captain/llm/assistant_chat_service.rb b/enterprise/app/services/captain/llm/assistant_chat_service.rb
index 689e16dfe..7f2113498 100644
--- a/enterprise/app/services/captain/llm/assistant_chat_service.rb
+++ b/enterprise/app/services/captain/llm/assistant_chat_service.rb
@@ -9,6 +9,7 @@ class Captain::Llm::AssistantChatService < Llm::BaseOpenAiService
     @tool_registry = Captain::ToolRegistryService.new(assistant)
     @messages = [system_message]
     @response = ''
+    register_tools
   end
 
   def generate_response(input, previous_messages = [], role = 'user')
@@ -19,6 +20,11 @@ class Captain::Llm::AssistantChatService < Llm::BaseOpenAiService
 
   private
 
+  def register_tools
+    @tool_registry = Captain::ToolRegistryService.new(@assistant)
+    @tool_registry.register_tool(Captain::Tools::SearchDocumentationService)
+  end
+
   def system_message
     {
       role: 'system',
diff --git a/enterprise/app/services/captain/tool_registry_service.rb b/enterprise/app/services/captain/tool_registry_service.rb
index 6063242b4..088d89483 100644
--- a/enterprise/app/services/captain/tool_registry_service.rb
+++ b/enterprise/app/services/captain/tool_registry_service.rb
@@ -5,7 +5,6 @@ class Captain::ToolRegistryService
     @assistant = assistant
     @registered_tools = []
     @tools = {}
-    register_default_tools
   end
 
   def register_tool(tool_class)
@@ -14,10 +13,6 @@ class Captain::ToolRegistryService
     @registered_tools << tool.to_registry_format
   end
 
-  def register_default_tools
-    register_tool(Captain::Tools::SearchDocumentationService)
-  end
-
   def method_missing(method_name, *arguments)
     if @tools.key?(method_name.to_s)
       @tools[method_name.to_s].execute(*arguments)
diff --git a/enterprise/app/services/captain/tools/search_documentation_service.rb b/enterprise/app/services/captain/tools/search_documentation_service.rb
index 72a85fdab..672baf24a 100644
--- a/enterprise/app/services/captain/tools/search_documentation_service.rb
+++ b/enterprise/app/services/captain/tools/search_documentation_service.rb
@@ -22,13 +22,13 @@ class Captain::Tools::SearchDocumentationService < Captain::Tools::BaseService
 
   def execute(arguments)
     query = arguments['search_query']
-    Rails.logger.debug { "[CAPTAIN][DocumentationSearch] #{query}" }
-    assistant
-      .responses
-      .approved
-      .search(query)
-      .map { |response| format_response(response) }
-      .join
+    Rails.logger.info { "#{self.class.name}: #{query}" }
+
+    responses = assistant.responses.approved.search(query)
+
+    return 'No FAQs found for the given query' if responses.empty?
+
+    responses.map { |response| format_response(response) }.join
   end
 
   private
diff --git a/spec/enterprise/services/captain/tool_registry_service_spec.rb b/spec/enterprise/services/captain/tool_registry_service_spec.rb
new file mode 100644
index 000000000..e355dea0a
--- /dev/null
+++ b/spec/enterprise/services/captain/tool_registry_service_spec.rb
@@ -0,0 +1,87 @@
+require 'rails_helper'
+
+# Test tool implementation
+class TestTool < Captain::Tools::BaseService
+  def name
+    'test_tool'
+  end
+
+  def description
+    'A test tool for specs'
+  end
+
+  def parameters
+    {
+      type: 'object',
+      properties: {
+        test_param: {
+          type: 'string'
+        }
+      }
+    }
+  end
+
+  def execute(*args)
+    args
+  end
+end
+
+RSpec.describe Captain::ToolRegistryService do
+  let(:assistant) { create(:captain_assistant) }
+  let(:service) { described_class.new(assistant) }
+
+  describe '#initialize' do
+    it 'initializes with empty tools and registered_tools' do
+      expect(service.tools).to be_empty
+      expect(service.registered_tools).to be_empty
+    end
+  end
+
+  describe '#register_tool' do
+    let(:tool_class) { TestTool }
+
+    it 'registers a new tool' do
+      service.register_tool(tool_class)
+
+      expect(service.tools['test_tool']).to be_a(TestTool)
+      expect(service.registered_tools).to include(
+        {
+          type: 'function',
+          function: {
+            name: 'test_tool',
+            description: 'A test tool for specs',
+            parameters: {
+              type: 'object',
+              properties: {
+                test_param: {
+                  type: 'string'
+                }
+              }
+            }
+          }
+        }
+      )
+    end
+  end
+
+  describe 'method_missing' do
+    let(:tool_class) { TestTool }
+
+    before do
+      service.register_tool(tool_class)
+    end
+
+    context 'when method corresponds to a registered tool' do
+      it 'executes the tool with given arguments' do
+        result = service.test_tool(test_param: 'arg1')
+        expect(result).to eq([{ test_param: 'arg1' }])
+      end
+    end
+
+    context 'when method does not correspond to a registered tool' do
+      it 'raises NoMethodError' do
+        expect { service.unknown_tool }.to raise_error(NoMethodError)
+      end
+    end
+  end
+end
diff --git a/spec/enterprise/services/captain/tools/search_documentation_service_spec.rb b/spec/enterprise/services/captain/tools/search_documentation_service_spec.rb
new file mode 100644
index 000000000..9f5586e6b
--- /dev/null
+++ b/spec/enterprise/services/captain/tools/search_documentation_service_spec.rb
@@ -0,0 +1,77 @@
+require 'rails_helper'
+
+RSpec.describe Captain::Tools::SearchDocumentationService do
+  let(:assistant) { create(:captain_assistant) }
+  let(:service) { described_class.new(assistant) }
+  let(:question) { 'How to create a new account?' }
+  let(:answer) { 'You can create a new account by clicking on the Sign Up button.' }
+  let(:external_link) { 'https://example.com/docs/create-account' }
+
+  describe '#name' do
+    it 'returns the correct service name' do
+      expect(service.name).to eq('search_documentation')
+    end
+  end
+
+  describe '#description' do
+    it 'returns the service description' do
+      expect(service.description).to eq('Search and retrieve documentation from knowledge base')
+    end
+  end
+
+  describe '#parameters' do
+    it 'returns the required parameters schema' do
+      expected_schema = {
+        type: 'object',
+        properties: {
+          search_query: {
+            type: 'string',
+            description: 'The search query to look up in the documentation.'
+          }
+        },
+        required: ['search_query']
+      }
+
+      expect(service.parameters).to eq(expected_schema)
+    end
+  end
+
+  describe '#execute' do
+    let!(:response) do
+      create(
+        :captain_assistant_response,
+        assistant: assistant,
+        question: question,
+        answer: answer,
+        status: 'approved'
+      )
+    end
+
+    let(:documentable) { create(:captain_document, external_link: external_link) }
+
+    context 'when matching responses exist' do
+      before do
+        response.update(documentable: documentable)
+        allow(Captain::AssistantResponse).to receive(:search).with(question).and_return([response])
+      end
+
+      it 'returns formatted responses for the search query' do
+        result = service.execute({ 'search_query' => question })
+
+        expect(result).to include(question)
+        expect(result).to include(answer)
+        expect(result).to include(external_link)
+      end
+    end
+
+    context 'when no matching responses exist' do
+      before do
+        allow(Captain::AssistantResponse).to receive(:search).with(question).and_return([])
+      end
+
+      it 'returns an empty string' do
+        expect(service.execute({ 'search_query' => question })).to eq('No FAQs found for the given query')
+      end
+    end
+  end
+end