Map<String, Object> context = null;

        if (session != null) {
            PluginDescriptor desc = new PluginDescriptor();
            desc.setGroupId(PluginDescriptor.getDefaultPluginGroupId());
            desc.setArtifactId(PluginDescriptor.getDefaultPluginArtifactId("toolchains"));

            MavenProject current = session.getCurrentProject();

        try {
            PluginDescriptor desc = descriptors.get(key);
            if (desc == null) {
                synchronized (key) {
                    desc = descriptors.get(key);
                    if (desc == null) {
                        desc = supplier.load();
                        descriptors.putIfAbsent(key, clone(desc));
                    }
                }
            }