diff --git a/src/modules/module-audio-dsp.c b/src/modules/module-audio-dsp.c
index 278c4ccac..6263df1f3 100644
--- a/src/modules/module-audio-dsp.c
+++ b/src/modules/module-audio-dsp.c
@@ -98,9 +98,7 @@ static void *create_object(void *_data,
 	struct factory_data *d = _data;
 	struct pw_client *client;
 	struct pw_node *dsp;
-	int res, maxbuffer;
-	const char *str;
-	enum pw_direction direction;
+	int res;
 	struct node_data *nd;
 	struct pw_resource *bound_resource;
 
@@ -109,24 +107,16 @@ static void *create_object(void *_data,
 
 	client = pw_resource_get_client(resource);
 
-	if ((str = pw_properties_get(properties, "audio-dsp.direction")) == NULL)
-		goto no_props;
-
-	direction = pw_properties_parse_int(str);
-
-	if ((str = pw_properties_get(properties, "audio-dsp.maxbuffer")) == NULL)
-		goto no_props;
-
-	maxbuffer = pw_properties_parse_int(str);
-
 	dsp = pw_audio_dsp_new(pw_module_get_core(d->module),
 			properties,
-			direction,
-			maxbuffer,
 			sizeof(struct node_data));
 
-	if (dsp == NULL)
-		goto no_mem;
+	if (dsp == NULL) {
+		if (errno == ENOMEM)
+			goto no_mem;
+		else
+			goto usage;
+	}
 
 	nd = pw_audio_dsp_get_user_data(dsp);
 	nd->data = d;
@@ -157,9 +147,9 @@ static void *create_object(void *_data,
 	pw_log_error("audio-dsp needs a resource");
 	pw_resource_error(resource, -EINVAL, "no resource");
 	goto done;
-      no_props:
-	pw_log_error("audio-dsp needs a property");
-	pw_resource_error(resource, -EINVAL, "no property");
+      usage:
+	pw_log_error("usage: "AUDIO_DSP_USAGE);
+	pw_resource_error(resource, -EINVAL, "usage: "AUDIO_DSP_USAGE);
 	goto done;
       no_mem:
 	pw_log_error("can't create node");
@@ -210,7 +200,9 @@ static int module_init(struct pw_module *module, struct pw_properties *propertie
 				 "audio-dsp",
 				 PW_TYPE_INTERFACE_Node,
 				 PW_VERSION_NODE_PROXY,
-				 NULL,
+				 pw_properties_new(
+					 PW_KEY_FACTORY_USAGE, AUDIO_DSP_USAGE,
+					 NULL),
 				 sizeof(*data));
 	if (factory == NULL)
 		return -ENOMEM;
diff --git a/src/modules/module-audio-dsp/audio-dsp.c b/src/modules/module-audio-dsp/audio-dsp.c
index 9ce459ee3..d9f0a70fc 100644
--- a/src/modules/module-audio-dsp/audio-dsp.c
+++ b/src/modules/module-audio-dsp/audio-dsp.c
@@ -258,8 +258,6 @@ static const struct pw_node_events node_events = {
 
 struct pw_node *pw_audio_dsp_new(struct pw_core *core,
 		const struct pw_properties *props,
-		enum pw_direction direction,
-		uint32_t max_buffer_size,
 		size_t user_data_size)
 {
 	struct pw_node *node;
@@ -267,10 +265,24 @@ struct pw_node *pw_audio_dsp_new(struct pw_core *core,
 	const char *api, *alias, *str, *factory;
 	char node_name[128];
 	struct pw_properties *pr;
+	enum pw_direction direction;
+	uint32_t max_buffer_size;
 	int i;
 
 	pr = pw_properties_copy(props);
 
+	if ((str = pw_properties_get(pr, "audio-dsp.direction")) == NULL) {
+		pw_log_error("missing audio-dsp.direction property");
+		goto error;
+	}
+	direction = pw_properties_parse_int(str);
+
+	if ((str = pw_properties_get(pr, "audio-dsp.maxbuffer")) == NULL) {
+		pw_log_error("missing audio-dsp.maxbuffer property");
+		goto error;
+	}
+	max_buffer_size = pw_properties_parse_int(str);
+
 	if ((api = pw_properties_get(pr, PW_KEY_DEVICE_API)) == NULL) {
 		pw_log_error("missing "PW_KEY_DEVICE_API" property");
 		goto error;
diff --git a/src/modules/module-audio-dsp/audio-dsp.h b/src/modules/module-audio-dsp/audio-dsp.h
index 24cdb9bc7..ce5e863ae 100644
--- a/src/modules/module-audio-dsp/audio-dsp.h
+++ b/src/modules/module-audio-dsp/audio-dsp.h
@@ -32,11 +32,15 @@
 extern "C" {
 #endif
 
+#define AUDIO_DSP_USAGE	"audio-dsp.direction=<enum spa_direction> "	\
+			"audio-dsp.maxbuffer=<int> "			\
+			"audio-dsp.name=<string> "			\
+			PW_KEY_DEVICE_API"=<string> "			\
+			"["PW_KEY_NODE_ID"=<int>]"
+
 struct pw_node *
 pw_audio_dsp_new(struct pw_core *core,
 		 const struct pw_properties *properties,
-		 enum pw_direction direction,
-		 uint32_t max_buffer_size,
 		 size_t user_data_size);
 
 void *pw_audio_dsp_get_user_data(struct pw_node *node);
diff --git a/src/modules/module-client-device.c b/src/modules/module-client-device.c
index c440eb4d1..0302ffc31 100644
--- a/src/modules/module-client-device.c
+++ b/src/modules/module-client-device.c
@@ -123,7 +123,9 @@ static int module_init(struct pw_module *module, struct pw_properties *propertie
 				 "client-device",
 				 SPA_TYPE_INTERFACE_Device,
 				 SPA_VERSION_DEVICE,
-				 NULL,
+				 pw_properties_new(
+					 PW_KEY_FACTORY_USAGE, CLIENT_DEVICE_USAGE,
+					 NULL),
 				 sizeof(*data));
 	if (factory == NULL)
 		return -ENOMEM;
diff --git a/src/modules/module-client-device/client-device.h b/src/modules/module-client-device/client-device.h
index 9dd702753..818c5c463 100644
--- a/src/modules/module-client-device/client-device.h
+++ b/src/modules/module-client-device/client-device.h
@@ -31,6 +31,8 @@
 extern "C" {
 #endif
 
+#define CLIENT_DEVICE_USAGE	"["PW_KEY_DEVICE_NAME"=<string>]"
+
 struct pw_device *
 pw_client_device_new(struct pw_resource *resource,
 		   struct pw_global *parent,
diff --git a/src/modules/module-link-factory.c b/src/modules/module-link-factory.c
index a9c3b04b5..8ed6b427a 100644
--- a/src/modules/module-link-factory.c
+++ b/src/modules/module-link-factory.c
@@ -320,7 +320,9 @@ static int module_init(struct pw_module *module, struct pw_properties *propertie
 				 "link-factory",
 				 PW_TYPE_INTERFACE_Link,
 				 PW_VERSION_LINK_PROXY,
-				 NULL,
+				 pw_properties_new(
+					 PW_KEY_FACTORY_USAGE, FACTORY_USAGE,
+					 NULL),
 				 sizeof(*data));
 	if (factory == NULL)
 		return -ENOMEM;
diff --git a/src/modules/spa/module-device-factory.c b/src/modules/spa/module-device-factory.c
index 7f09ea552..dadb7cd10 100644
--- a/src/modules/spa/module-device-factory.c
+++ b/src/modules/spa/module-device-factory.c
@@ -91,7 +91,7 @@ static void *create_object(void *_data,
 	if (factory_name == NULL)
 		goto no_properties;
 
-	name = pw_properties_get(properties, "name");
+	name = pw_properties_get(properties, PW_KEY_DEVICE_NAME);
 	if (name == NULL)
 		name = "spa-device";
 
diff --git a/src/modules/spa/module-node-factory.c b/src/modules/spa/module-node-factory.c
index c2de801a3..ec666dc71 100644
--- a/src/modules/spa/module-node-factory.c
+++ b/src/modules/spa/module-node-factory.c
@@ -91,7 +91,7 @@ static void *create_object(void *_data,
 	if (factory_name == NULL)
 		goto no_properties;
 
-	name = pw_properties_get(properties, "name");
+	name = pw_properties_get(properties, PW_KEY_NODE_NAME);
 	if (name == NULL)
 		name = "spa-node";
 
diff --git a/src/pipewire/keys.h b/src/pipewire/keys.h
index b0750761c..2b91d2e87 100644
--- a/src/pipewire/keys.h
+++ b/src/pipewire/keys.h
@@ -180,6 +180,7 @@ extern "C" {
 
 /** Factory properties */
 #define PW_KEY_FACTORY_NAME		"factory.name"		/**< the name of the factory */
+#define PW_KEY_FACTORY_USAGE		"factory.usage"		/**< the usage of the factory */
 #define PW_KEY_FACTORY_TYPE_NAME	"factory.type.name"	/**< the name of the type created by a factory */
 #define PW_KEY_FACTORY_TYPE_VERSION	"factory.type.version"	/**< the version of the type created by a factory */