diff --git a/src/nostalgia/tools/pack/pack.cpp b/src/nostalgia/tools/pack/pack.cpp
index a3a072e0..2ba305c3 100644
--- a/src/nostalgia/tools/pack/pack.cpp
+++ b/src/nostalgia/tools/pack/pack.cpp
@@ -14,18 +14,22 @@
 namespace nostalgia {
 
 /**
- * Convert path references to inodes to save space
+ * Convert path references in Claw data to inodes to save space
  * @param buff buffer holding file
  * @return error
  * stub for now
  */
 static ox::Result<ox::Buffer> pathToInode(const ox::Buffer &buff) noexcept {
-	return ox::move(buff);
+	return std::move(buff);
 }
 
 // just strip header for now...
 static ox::Result<ox::Buffer> toMetalClaw(const ox::Buffer &buff) noexcept {
-	return ox::stripClawHeader(buff.data(), buff.size());
+	oxRequire(hdr, ox::readClawHeader(buff));
+	if (hdr.fmt != ox::ClawFormat::Metal) {
+		return OxError(1, "Cannot convert from Claw to MetalClaw, data portion must already be MetalClaw");
+	}
+	return ox::stripClawHeader(buff);
 }
 
 static ox::Error doTransformations(ox::FileSystem *dest, const ox::String &filePath) noexcept {