probe

probe/src/main/java/art/arcane/iris/probe/StubPlatform.java

@@ -529,6 +529,23 @@ public final class StubPlatform implements IrisPlatform {
         }
     }
 
+    private record StubEntityType(String key) implements PlatformEntityType {
+        @Override
+        public String namespace() {
+            return "minecraft";
+        }
+
+        @Override
+        public String spawnCategory() {
+            return "monster";
+        }
+
+        @Override
+        public Object nativeHandle() {
+            return this;
+        }
+    }
+
     private static final class StubRegistries implements PlatformRegistries {
         @Override
         public PlatformBlockState block(String key) {
@@ -567,7 +584,7 @@ public final class StubPlatform implements IrisPlatform {
 
         @Override
         public PlatformEntityType entity(String key) {
-            return null;
+            return key != null && key.startsWith("minecraft:") ? new StubEntityType(key) : null;
         }
 
         @Override

probe/src/test/java/art/arcane/iris/probe/GenerationProbeTest.java

@@ -8,6 +8,8 @@ import java.util.List;
 import java.util.Set;
 
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertNull;
 import static org.junit.Assert.assertThrows;
 import static org.junit.Assert.assertTrue;
 
@@ -78,4 +80,12 @@ public final class GenerationProbeTest {
                 "IRIS_GENPROBE_RESULT version=1 status=PASS dimension=underworld warmup_chunks=2 measured_chunks=4 successful_chunks=6 failed_chunks=0 engine_ready_ms=5.000 first_chunk_ms=6.000 measured_median_ms=10.000 measured_p95_ms=20.000 measured_max_ms=30.000 measured_total_ms=40.000 measured_cps=100.000 signature=0123456789abcdef",
                 result.machineLine());
     }
+
+    @Test
+    public void offlineProbeResolvesVanillaEntitiesWithoutInventingExternalKeys() {
+        StubPlatform platform = new StubPlatform(new File("/tmp/iris-probe-test"));
+
+        assertNotNull(platform.registries().entity("minecraft:slime"));
+        assertNull(platform.registries().entity("external:missing"));
+    }
 }