diff --git a/src/libeis-client.c b/src/libeis-client.c
index ccc812d..311e9cf 100644
--- a/src/libeis-client.c
+++ b/src/libeis-client.c
@@ -113,6 +113,8 @@ eis_client_connect(struct eis_client *client)
 	case EIS_CLIENT_STATE_CONNECTING:
 		break;
 	default:
+		log_bug_client(eis_client_get_context(client),
+			       "%s: client already connected\n", __func__);
 		return;
 	}
 
diff --git a/src/libeis-device.c b/src/libeis-device.c
index 77e19c7..4037776 100644
--- a/src/libeis-device.c
+++ b/src/libeis-device.c
@@ -78,18 +78,33 @@ eis_keymap_new(enum eis_keymap_type type, int fd, size_t size)
 	return eis_keymap_ref(keymap);
 }
 
+static inline struct eis *
+eis_device_get_context(struct eis_device *device)
+{
+	return eis_client_get_context(eis_device_get_client(device));
+}
+
 _public_ void
 eis_device_keyboard_set_keymap(struct eis_device *device,
 			       struct eis_keymap *keymap)
 {
-	if (device->state != EIS_DEVICE_STATE_NEW)
+	if (device->state != EIS_DEVICE_STATE_NEW) {
+		log_bug_client(eis_device_get_context(device),
+			       "%s: device already (dis)connected\n", __func__);
 		return;
+	}
 
-	if (device->keymap && !device->keymap->is_client_keymap)
+	if (device->keymap && !device->keymap->is_client_keymap) {
+		log_bug_client(eis_device_get_context(device),
+			       "%s: keymap can only be configured once\n", __func__);
 		return;
+	}
 
-	if (keymap && keymap->assigned)
+	if (keymap && keymap->assigned) {
+		log_bug_client(eis_device_get_context(device),
+			       "%s: keymaps cannot be re-used\n", __func__);
 		return;
+	}
 
 	device->keymap = eis_keymap_unref(device->keymap);
 	if (keymap) {
@@ -129,8 +144,11 @@ OBJECT_IMPLEMENT_GETTER(eis_device, name, const char *);
 _public_ void
 eis_device_set_name(struct eis_device *device, const char *name)
 {
-	if (device->state != EIS_DEVICE_STATE_NEW)
+	if (device->state != EIS_DEVICE_STATE_NEW) {
+		log_bug_client(eis_device_get_context(device),
+			       "%s: device already (dis)connected\n", __func__);
 		return;
+	}
 
 	free(device->name);
 	device->name = xstrdup(name);
@@ -180,13 +198,19 @@ eis_device_set_client_keymap(struct eis_device *device,
 			     enum eis_keymap_type type,
 			     int keymap_fd, size_t size)
 {
-	if (device->state != EIS_DEVICE_STATE_NEW)
+	if (device->state != EIS_DEVICE_STATE_NEW) {
+		log_bug(eis_device_get_context(device),
+			"%s: device already (dis)connected\n", __func__);
 		return;
+	}
 
 	_cleanup_eis_keymap_ struct eis_keymap *keymap =
 		eis_keymap_new(type, keymap_fd, size);
-	if (!keymap)
+	if (!keymap) {
+		log_bug(eis_device_get_context(device),
+			"%s: keymap creation failed, using NULL keymap\n", __func__);
 		return;
+	}
 
 	eis_device_keyboard_set_keymap(device, keymap);
 	keymap->is_client_keymap = true;
@@ -249,8 +273,11 @@ int
 eis_device_pointer_rel(struct eis_device *device,
 		       double x, double y)
 {
-	if (!eis_device_has_capability(device, EIS_DEVICE_CAP_POINTER))
+	if (!eis_device_has_capability(device, EIS_DEVICE_CAP_POINTER)) {
+		log_bug_client(eis_device_get_context(device),
+			       "%s: device is not a pointer\n", __func__);
 		return -EINVAL;
+	}
 
 	if (device->state != EIS_DEVICE_STATE_RESUMED)
 		return -EINVAL;
@@ -264,8 +291,11 @@ int
 eis_device_pointer_abs(struct eis_device *device,
 		       double x, double y)
 {
-	if (!eis_device_has_capability(device, EIS_DEVICE_CAP_POINTER_ABSOLUTE))
+	if (!eis_device_has_capability(device, EIS_DEVICE_CAP_POINTER_ABSOLUTE)) {
+		log_bug_client(eis_device_get_context(device),
+			       "%s: device is not an absolute pointer\n", __func__);
 		return -EINVAL;
+	}
 
 	if (device->state != EIS_DEVICE_STATE_RESUMED)
 		return -EINVAL;
@@ -283,8 +313,11 @@ int
 eis_device_pointer_button(struct eis_device *device,
 		          uint32_t button, bool is_press)
 {
-	if (!eis_device_has_capability(device, EIS_DEVICE_CAP_POINTER))
+	if (!eis_device_has_capability(device, EIS_DEVICE_CAP_POINTER)) {
+		log_bug_client(eis_device_get_context(device),
+			       "%s: device is not a pointer\n", __func__);
 		return -EINVAL;
+	}
 
 	if (device->state != EIS_DEVICE_STATE_RESUMED)
 		return -EINVAL;
@@ -298,8 +331,11 @@ int
 eis_device_keyboard_key(struct eis_device *device,
 			uint32_t key, bool is_press)
 {
-	if (!eis_device_has_capability(device, EIS_DEVICE_CAP_KEYBOARD))
+	if (!eis_device_has_capability(device, EIS_DEVICE_CAP_KEYBOARD)) {
+		log_bug_client(eis_device_get_context(device),
+			       "%s: device is not a keyboard\n", __func__);
 		return -EINVAL;
+	}
 
 	if (device->state != EIS_DEVICE_STATE_RESUMED)
 		return -EINVAL;
@@ -314,8 +350,11 @@ eis_device_touch(struct eis_device *device, uint32_t touchid,
 		 bool is_down, bool is_up,
 		 double x, double y)
 {
-	if (!eis_device_has_capability(device, EIS_DEVICE_CAP_TOUCH))
+	if (!eis_device_has_capability(device, EIS_DEVICE_CAP_TOUCH)) {
+		log_bug_client(eis_device_get_context(device),
+			       "%s: device is not a touch device\n", __func__);
 		return -EINVAL;
+	}
 
 	if (device->state != EIS_DEVICE_STATE_RESUMED)
 		return -EINVAL;
@@ -333,12 +372,14 @@ eis_device_touch(struct eis_device *device, uint32_t touchid,
 _public_ void
 eis_device_connect(struct eis_device *device)
 {
-	if (device->state != EIS_DEVICE_STATE_NEW)
+	if (device->state != EIS_DEVICE_STATE_NEW) {
+		log_bug_client(eis_device_get_context(device),
+			       "%s: device is already (dis)connected\n", __func__);
 		return;
+	}
 
 	if (device->capabilities_mask == 0) {
-		struct eis_client *client = eis_device_get_client(device);
-		log_bug(eis_client_get_context(client),
+		log_bug(eis_device_get_context(device),
 			"Connecting a device without capabilities\n");
 		eis_device_disconnect(device);
 		return;
diff --git a/src/libeis-event.c b/src/libeis-event.c
index c001e6c..ecb0b1d 100644
--- a/src/libeis-event.c
+++ b/src/libeis-event.c
@@ -127,9 +127,9 @@ check_event_type(struct eis_event *event,
 	va_end(args);
 
 	if (!rc)
-		log_bug(eis_event_get_context(event),
-			"Invalid event type %d passed to %s()\n",
-			type, function_name);
+		log_bug_client(eis_event_get_context(event),
+			       "Invalid event type %d passed to %s()\n",
+			       type, function_name);
 
 	return rc;
 }
diff --git a/src/libeis-private.h b/src/libeis-private.h
index e753fee..93500ab 100644
--- a/src/libeis-private.h
+++ b/src/libeis-private.h
@@ -277,4 +277,6 @@ eis_log_msg_va(struct eis *eis,
 #define log_error(T_, ...) \
 	eis_log_msg((T_), EIS_LOG_PRIORITY_ERROR, __VA_ARGS__)
 #define log_bug(T_, ...) \
-	eis_log_msg((T_), EIS_LOG_PRIORITY_ERROR, "🪳  BUG:  " __VA_ARGS__)
+	eis_log_msg((T_), EIS_LOG_PRIORITY_ERROR, "🪳  libeis bug:  " __VA_ARGS__)
+#define log_bug_client(T_, ...) \
+	eis_log_msg((T_), EIS_LOG_PRIORITY_ERROR, "🪲  Bug: " __VA_ARGS__)