diff --git a/CHANGELOG.md b/CHANGELOG.md
index 6b2e47d6..7aabaf8f 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,9 @@
 ## [Unreleased]
 
+### Added
+
+- [OpenAPI] Add `openapi:validate` Rake task for OpenAPI tags validation (#163).
+
 ## [1.27.0] - 2026-08-06
 
 ### Added
diff --git a/lib/rage/openapi/openapi.rb b/lib/rage/openapi/openapi.rb
index a7c89b99..3c7889e3 100644
--- a/lib/rage/openapi/openapi.rb
+++ b/lib/rage/openapi/openapi.rb
@@ -200,9 +200,20 @@ def self.__resolve_resource(klass_str, namespace)
 
   # @private
   def self.__log_warn(log)
+    @__warnings << log if @__warnings
     puts "[OpenAPI] WARNING: #{log}"
   end
 
+  # @private
+  # @return [Array<String>] the warnings logged inside the block
+  def self.__collect_warnings
+    @__warnings = []
+    yield
+    @__warnings
+  ensure
+    @__warnings = nil
+  end
+
   module Nodes
   end
 
diff --git a/lib/rage/tasks.rb b/lib/rage/tasks.rb
index 80c10ad8..7da34bf3 100644
--- a/lib/rage/tasks.rb
+++ b/lib/rage/tasks.rb
@@ -7,6 +7,7 @@ class Rage::Tasks
   class << self
     def init
       load_db_tasks if defined?(StandaloneMigrations)
+      load_rage_tasks
       load_app_tasks
     end
 
@@ -40,5 +41,9 @@ def configuration_file
     def load_app_tasks
       Dir[Rage.root.join("lib/tasks/**/*.rake")].each { |file| load file }
     end
+
+    def load_rage_tasks
+      Dir[File.expand_path("tasks/**/*.rake", __dir__)].each { |file| load file }
+    end
   end
 end
diff --git a/lib/rage/tasks/openapi.rake b/lib/rage/tasks/openapi.rake
new file mode 100644
index 00000000..f46c7915
--- /dev/null
+++ b/lib/rage/tasks/openapi.rake
@@ -0,0 +1,14 @@
+namespace :openapi do
+  desc "Validate OpenAPI tags and fail if any warnings were produced"
+  task :validate do
+    abort "OpenAPI validation requires a booted application." unless Rage.config.internal.initialized?
+
+    warnings = Rage::OpenAPI.__collect_warnings { Rage::OpenAPI.build }
+
+    if warnings.any?
+      abort "OpenAPI validation failed with #{warnings.size} warning(s)."
+    else
+      puts "OpenAPI validation passed without warnings."
+    end
+  end
+end
diff --git a/spec/openapi/openapi_spec.rb b/spec/openapi/openapi_spec.rb
index e71187fa..3dba6809 100644
--- a/spec/openapi/openapi_spec.rb
+++ b/spec/openapi/openapi_spec.rb
@@ -249,6 +249,55 @@
     end
   end
 
+  describe ".__log_warn" do
+    it "prints a warning" do
+      expect { described_class.__log_warn("something went wrong") }.
+        to output("[OpenAPI] WARNING: something went wrong\n").to_stdout
+    end
+
+    it "does not retain the warning when not collecting" do
+      allow(described_class).to receive(:puts)
+
+      described_class.__log_warn("something went wrong")
+
+      expect(described_class.instance_variable_get(:@__warnings)).to be_nil
+    end
+  end
+
+  describe ".__collect_warnings" do
+    before do
+      allow(described_class).to receive(:puts)
+    end
+
+    it "returns the warnings logged inside the block" do
+      warnings = described_class.__collect_warnings do
+        described_class.__log_warn("first")
+        described_class.__log_warn("second")
+      end
+
+      expect(warnings).to eq(["first", "second"])
+    end
+
+    it "returns an empty array when nothing was logged" do
+      expect(described_class.__collect_warnings {}).to eq([])
+    end
+
+    it "stops collecting once the block returns" do
+      described_class.__collect_warnings { described_class.__log_warn("first") }
+      described_class.__log_warn("second")
+
+      expect(described_class.__collect_warnings {}).to eq([])
+    end
+
+    it "stops collecting if the block raises" do
+      expect {
+        described_class.__collect_warnings { raise "boom" }
+      }.to raise_error("boom")
+
+      expect(described_class.instance_variable_get(:@__warnings)).to be_nil
+    end
+  end
+
   describe ".__type_to_spec" do
     subject { described_class.__type_to_spec(type) }
 
diff --git a/spec/rage/tasks_spec.rb b/spec/rage/tasks_spec.rb
new file mode 100644
index 00000000..f05a58f2
--- /dev/null
+++ b/spec/rage/tasks_spec.rb
@@ -0,0 +1,123 @@
+# frozen_string_literal: true
+
+require "rake"
+require "rage/tasks"
+
+RSpec.describe Rage::Tasks do
+  # `Rake.application` is a process-wide singleton owning the task registry; a fresh one per example
+  # keeps the registry empty and tasks re-invokable, while restoring it avoids leaking into other specs.
+  around do |example|
+    original_application = Rake.application
+    Rake.application = Rake::Application.new
+    example.run
+  ensure
+    Rake.application = original_application
+  end
+
+  describe ".load_rage_tasks" do
+    it "loads the openapi:validate task" do
+      expect(Rake::Task.task_defined?("openapi:validate")).to eq(false)
+
+      described_class.send(:load_rage_tasks)
+
+      expect(Rake::Task.task_defined?("openapi:validate")).to eq(true)
+    end
+  end
+end
+
+RSpec.describe "openapi:validate" do
+  include_context "mocked_classes"
+  include_context "mocked_rage_routes"
+
+  around do |example|
+    original_application = Rake.application
+    Rake.application = Rake::Application.new
+    Rage::Tasks.send(:load_rage_tasks)
+    example.run
+  ensure
+    Rake.application = original_application
+  end
+
+  before do
+    allow(Rage.config.internal).to receive(:initialized?).and_return(true)
+  end
+
+  let(:routes) do
+    { "GET /users" => "UsersController#index" }
+  end
+
+  # returns the `SystemExit` error the task exited with, or `nil` if it didn't exit
+  subject(:invoke_task) do
+    Rake::Task["openapi:validate"].invoke
+    nil
+  rescue SystemExit => e
+    e
+  end
+
+  context "when the application is not booted" do
+    before do
+      allow(Rage.config.internal).to receive(:initialized?).and_return(false)
+    end
+
+    it "doesn't build the spec" do
+      expect(Rage::OpenAPI).not_to receive(:build)
+
+      expect { invoke_task }.
+        to output(/OpenAPI validation requires a booted application\./).to_stderr
+    end
+
+    it "exits with status 1" do
+      exit_error = nil
+
+      expect { exit_error = invoke_task }.to output.to_stderr
+
+      expect(exit_error.status).to eq(1)
+    end
+  end
+
+  context "when the spec builds without warnings" do
+    let_class("UsersController", parent: RageController::API) do
+      <<~'RUBY'
+        # @response { id: Integer, full_name: String }
+        def index
+        end
+      RUBY
+    end
+
+    it "prints a success message" do
+      expect { invoke_task }.to output(/OpenAPI validation passed without warnings\./).to_stdout
+    end
+
+    it "doesn't exit with an error" do
+      allow($stdout).to receive(:puts)
+
+      expect(invoke_task).to be_nil
+    end
+  end
+
+  context "when the build produces warnings" do
+    let_class("UsersController", parent: RageController::API) do
+      <<~'RUBY'
+        # @response UnknownResource
+        def index
+        end
+      RUBY
+    end
+
+    it "prints the warnings and the number of failures" do
+      expect { invoke_task }.
+        to output(/unrecognized `@response` tag detected/).to_stdout.
+        and output(/OpenAPI validation failed with 1 warning\(s\)\./).to_stderr
+    end
+
+    it "exits with status 1" do
+      allow($stdout).to receive(:puts)
+
+      exit_error = nil
+
+      expect { exit_error = invoke_task }.to output.to_stderr
+
+      expect(exit_error.status).to eq(1)
+    end
+  end
+end