diff --git a/lib/last_fm/album.ex b/lib/last_fm/album.ex
index a7ed33e7..fb2964ae 100644
--- a/lib/last_fm/album.ex
+++ b/lib/last_fm/album.ex
@@ -1,4 +1,5 @@
 defmodule LastFm.Album do
+  @enforce_keys [:musicbrainz_id, :title]
   defstruct [:musicbrainz_id, :title]
 
   @type t :: %__MODULE__{
diff --git a/lib/last_fm/artist.ex b/lib/last_fm/artist.ex
index 2f815209..5b0f036b 100644
--- a/lib/last_fm/artist.ex
+++ b/lib/last_fm/artist.ex
@@ -1,4 +1,5 @@
 defmodule LastFm.Artist do
+  @enforce_keys [:musicbrainz_id, :name]
   defstruct [:musicbrainz_id, :name, :bio, :image, :play_count]
 
   @type t :: %__MODULE__{
diff --git a/lib/last_fm/config.ex b/lib/last_fm/config.ex
index 5b2df3a9..1472ee8f 100644
--- a/lib/last_fm/config.ex
+++ b/lib/last_fm/config.ex
@@ -8,6 +8,7 @@ defmodule LastFm.Config do
           user_agent: String.t()
         }
 
+  @enforce_keys [:api, :api_key, :user]
   defstruct api: LastFm.Api,
             api_key: "",
             user: "",
diff --git a/lib/last_fm/track.ex b/lib/last_fm/track.ex
index f055bf39..20cf3df3 100644
--- a/lib/last_fm/track.ex
+++ b/lib/last_fm/track.ex
@@ -7,6 +7,15 @@ defmodule LastFm.Track do
 
   alias LastFm.{Album, Artist}
 
+  @enforce_keys [
+    :musicbrainz_id,
+    :title,
+    :artist,
+    :album,
+    :cover_url,
+    :scrobbled_at_uts,
+    :scrobbled_at_label
+  ]
   defstruct [
     :musicbrainz_id,
     :title,
diff --git a/lib/music_brainz/config.ex b/lib/music_brainz/config.ex
index d6b64bb4..4ba13487 100644
--- a/lib/music_brainz/config.ex
+++ b/lib/music_brainz/config.ex
@@ -4,6 +4,7 @@ defmodule MusicBrainz.Config do
           user_agent: String.t()
         }
 
+  @enforce_keys [:api, :user_agent]
   defstruct api: MusicBrainz.APIImpl,
             user_agent: "change me"
 
diff --git a/lib/music_brainz/release_group.ex b/lib/music_brainz/release_group.ex
index 5ae0dbcd..0b69cde9 100644
--- a/lib/music_brainz/release_group.ex
+++ b/lib/music_brainz/release_group.ex
@@ -1,4 +1,5 @@
 defmodule MusicBrainz.ReleaseGroup do
+  @enforce_keys [:id, :type, :title, :artists, :release]
   defstruct [:id, :type, :title, :artists, :release]
 
   def from_api_response(rg) do
diff --git a/lib/obsidian/entry.ex b/lib/obsidian/entry.ex
index 9f2e93a2..e563390e 100644
--- a/lib/obsidian/entry.ex
+++ b/lib/obsidian/entry.ex
@@ -1,3 +1,4 @@
 defmodule Obsidian.Entry do
+  @enforce_keys [:type, :musicbrainz_id, :title, :release, :cover_url, :genres]
   defstruct [:type, :musicbrainz_id, :title, :release, :cover_url, :genres]
 end
diff --git a/lib/open_ai/completion.ex b/lib/open_ai/completion.ex
index 3577957e..842e7795 100644
--- a/lib/open_ai/completion.ex
+++ b/lib/open_ai/completion.ex
@@ -1,4 +1,5 @@
 defmodule OpenAI.Completion do
+  @enforce_keys [:content]
   defstruct content: "",
             temperature: 0.2,
             role: "user",