Agent throws exceptions on missing or empty descriptions

SEVERE: Failed to generate event class for JFRTransformDescriptor method:toString()Ljava/lang/String;, eventName:StringBuilder.toString(), #params:0
java.lang.IllegalArgumentException: value null
        at org.openjdk.jmc.internal.org.objectweb.asm.SymbolTable.addConstant(SymbolTable.java:501)
        at org.openjdk.jmc.internal.org.objectweb.asm.AnnotationWriter.visit(AnnotationWriter.java:259)
        at org.openjdk.jmc.agent.jfr.impl.JFREventClassGenerator.generateClassAnnotations(JFREventClassGenerator.java:231)
        at org.openjdk.jmc.agent.jfr.impl.JFREventClassGenerator.generateEventClass(JFREventClassGenerator.java:70)
        at org.openjdk.jmc.agent.jfr.impl.JFRClassVisitor.generateEventClass(JFRClassVisitor.java:109)
        at org.openjdk.jmc.agent.jfr.impl.JFRClassVisitor.visitEnd(JFRClassVisitor.java:89)
        at org.openjdk.jmc.internal.org.objectweb.asm.ClassReader.accept(ClassReader.java:722)
        at org.openjdk.jmc.internal.org.objectweb.asm.ClassReader.accept(ClassReader.java:401)
        at org.openjdk.jmc.agent.Transformer.doJFRLogging(Transformer.java:104)
        at org.openjdk.jmc.agent.Transformer.doTransform(Transformer.java:85)
        at org.openjdk.jmc.agent.Transformer.doTransforms(Transformer.java:75)
        at org.openjdk.jmc.agent.Transformer.transform(Transformer.java:63)
        at java.instrument/java.lang.instrument.ClassFileTransformer.transform(ClassFileTransformer.java:246)
        at java.instrument/sun.instrument.TransformerManager.transform(TransformerManager.java:188)
        at java.instrument/sun.instrument.InstrumentationImpl.transform(InstrumentationImpl.java:563)
        at java.instrument/sun.instrument.InstrumentationImpl.retransformClasses0(Native Method)
        at java.instrument/sun.instrument.InstrumentationImpl.retransformClasses(InstrumentationImpl.java:167)
        at org.openjdk.jmc.agent.jmx.AgentController.defineEventProbes(AgentController.java:80)
        at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
        at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.base/java.lang.reflect.Method.invoke(Method.java:566)
        at sun.reflect.misc.Trampoline.invoke(MethodUtil.java:71)
        at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
        at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.base/java.lang.reflect.Method.invoke(Method.java:566)
        at java.base/sun.reflect.misc.MethodUtil.invoke(MethodUtil.java:260)
        at java.management/com.sun.jmx.mbeanserver.ConvertingMethod.invokeWithOpenReturn(ConvertingMethod.java:193)
        at java.management/com.sun.jmx.mbeanserver.ConvertingMethod.invokeWithOpenReturn(ConvertingMethod.java:175)
        at java.management/com.sun.jmx.mbeanserver.MXBeanIntrospector.invokeM2(MXBeanIntrospector.java:117)
        at java.management/com.sun.jmx.mbeanserver.MXBeanIntrospector.invokeM2(MXBeanIntrospector.java:54)
        at java.management/com.sun.jmx.mbeanserver.MBeanIntrospector.invokeM(MBeanIntrospector.java:237)
        at java.management/com.sun.jmx.mbeanserver.PerInterface.invoke(PerInterface.java:138)
        at java.management/com.sun.jmx.mbeanserver.MBeanSupport.invoke(MBeanSupport.java:252)
        at java.management/com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.invoke(DefaultMBeanServerInterceptor.java:809)
        at java.management/com.sun.jmx.mbeanserver.JmxMBeanServer.invoke(JmxMBeanServer.java:801)
        at example.jfr/examples.UniversalConverter.defineProbes(UniversalConverter.java:359)
        at example.jfr/examples.EmptyDescriptionTest.main(EmptyDescriptionTest.java:6)