diff --git a/lib/livebook/runtime/evaluator/io_proxy.ex b/lib/livebook/runtime/evaluator/io_proxy.ex
index 71123369f..5b6b11f9f 100644
--- a/lib/livebook/runtime/evaluator/io_proxy.ex
+++ b/lib/livebook/runtime/evaluator/io_proxy.ex
@@ -58,7 +58,7 @@ defmodule Livebook.Runtime.Evaluator.IOProxy do
   @doc """
   Flushes any buffered output and returns gathered metadata.
   """
-  @spec after_evaluation(pid()) :: %{tracer_info: %Evaluator.Tracer{}}
+  @spec after_evaluation(pid()) :: %{tracer_info: Evaluator.Tracer.t()}
   def after_evaluation(pid) do
     GenServer.call(pid, :after_evaluation)
   end
diff --git a/lib/livebook/runtime/evaluator/tracer.ex b/lib/livebook/runtime/evaluator/tracer.ex
index 82e601f7c..82895974c 100644
--- a/lib/livebook/runtime/evaluator/tracer.ex
+++ b/lib/livebook/runtime/evaluator/tracer.ex
@@ -19,6 +19,18 @@ defmodule Livebook.Runtime.Evaluator.Tracer do
             imports_defined?: false,
             undefined_vars: MapSet.new()
 
+  @type t :: %__MODULE__{
+          modules_used: MapSet.t(),
+          modules_defined: map(),
+          aliases_used: MapSet.t(),
+          aliases_defined: map(),
+          requires_used: MapSet.t(),
+          requires_defined: MapSet.t(),
+          imports_used?: boolean(),
+          imports_defined?: boolean(),
+          undefined_vars: MapSet.t()
+        }
+
   @doc false
   def trace(event, env) do
     case event_to_updates(event, env) do