diff --git a/custom_assets/jak1/levels/test-zone/test-zone.jsonc b/custom_assets/jak1/levels/test-zone/test-zone.jsonc
index a08d1b62ee..3e7bd77a05 100644
--- a/custom_assets/jak1/levels/test-zone/test-zone.jsonc
+++ b/custom_assets/jak1/levels/test-zone/test-zone.jsonc
@@ -1,6 +1,7 @@
 {
   // The "in-game" name of the level. Should be lower case, with dashes (GOAL symbol name)
   // the name of this file, and the folder this file is in must have the same name.
+  // The long_name must also be 10 characters or fewer.
   "long_name": "test-zone",
   // The file name, should be upper case and 8 characters or less.
   "iso_name": "TESTZONE",
diff --git a/custom_assets/jak2/levels/test-zone/test-zone.jsonc b/custom_assets/jak2/levels/test-zone/test-zone.jsonc
index 78dce59c8f..5953484bd8 100644
--- a/custom_assets/jak2/levels/test-zone/test-zone.jsonc
+++ b/custom_assets/jak2/levels/test-zone/test-zone.jsonc
@@ -1,6 +1,7 @@
 {
   // The "in-game" name of the level. Should be lower case, with dashes (GOAL symbol name)
   // the name of this file, and the folder this file is in must have the same name.
+  // The long_name must also be 10 characters or fewer.
   "long_name": "test-zone",
   // The file name, should be upper case and 8 characters or less.
   "iso_name": "TESTZONE",
diff --git a/custom_assets/jak3/levels/test-zone/test-zone.jsonc b/custom_assets/jak3/levels/test-zone/test-zone.jsonc
index cd852780df..af145a51b1 100644
--- a/custom_assets/jak3/levels/test-zone/test-zone.jsonc
+++ b/custom_assets/jak3/levels/test-zone/test-zone.jsonc
@@ -1,6 +1,7 @@
 {
   // The "in-game" name of the level. Should be lower case, with dashes (GOAL symbol name)
   // the name of this file, and the folder this file is in must have the same name.
+  // The long_name must also be 10 characters or fewer.
   "long_name": "test-zone",
   // The file name, should be upper case and 8 characters or less.
   "iso_name": "TESTZONE",
diff --git a/goalc/build_level/jak1/build_level.cpp b/goalc/build_level/jak1/build_level.cpp
index 9513bf5596..52d6fa2ee1 100644
--- a/goalc/build_level/jak1/build_level.cpp
+++ b/goalc/build_level/jak1/build_level.cpp
@@ -48,6 +48,9 @@ bool run_build_level(const std::string& input_file,
   // unk zero
   // name
   file.name = level_json.at("long_name").get<std::string>();
+  ASSERT_MSG(file.name.size() <= 10,
+             fmt::format("long_name over 10 characters ({} characters): '{}'", file.name.size(),
+                         file.name));
   // nick
   file.nickname = level_json.at("nickname").get<std::string>();
   // vis infos
diff --git a/goalc/build_level/jak2/build_level.cpp b/goalc/build_level/jak2/build_level.cpp
index 7a65489e8c..b350ffac9a 100644
--- a/goalc/build_level/jak2/build_level.cpp
+++ b/goalc/build_level/jak2/build_level.cpp
@@ -42,6 +42,9 @@ bool run_build_level(const std::string& input_file,
   // unk zero
   // name
   file.name = level_json.at("long_name").get<std::string>();
+  ASSERT_MSG(file.name.size() <= 10,
+             fmt::format("long_name over 10 characters ({} characters): '{}'", file.name.size(),
+                         file.name));
   // nick
   file.nickname = level_json.at("nickname").get<std::string>();
   // vis infos
diff --git a/goalc/build_level/jak3/build_level.cpp b/goalc/build_level/jak3/build_level.cpp
index e83e220760..932ae679ff 100644
--- a/goalc/build_level/jak3/build_level.cpp
+++ b/goalc/build_level/jak3/build_level.cpp
@@ -40,6 +40,9 @@ bool run_build_level(const std::string& input_file,
   // unk zero
   // name
   file.name = level_json.at("long_name").get<std::string>();
+  ASSERT_MSG(file.name.size() <= 10,
+             fmt::format("long_name over 10 characters ({} characters): '{}'", file.name.size(),
+                         file.name));
   // nick
   file.nickname = level_json.at("nickname").get<std::string>();
   // vis infos