diff --git a/include/coap/resource.h b/include/coap/resource.h
index b8f206c9..5fec9526 100644
--- a/include/coap/resource.h
+++ b/include/coap/resource.h
@@ -115,10 +115,27 @@ typedef struct coap_resource_t {
  * of length @p len. This function returns the new coap_resource_t object.
  *
  * @param uri_path The URI path of the new resource.
- * @param len     The length of @p uri_path.
- * @param flags   Flags for memory management (in particular release of memory).
+ * @param len      The length of @p uri_path.
+ * @param flags    Flags for memory management (in particular release of
+ *                 memory). Possible values:@n
  *
- * @return       A pointer to the new object or @c NULL on error.
+ *                 COAP_RESOURCE_FLAGS_RELEASE_URI
+ *                  If this flag is set, the URI passed to
+ *                  coap_resource_init() is free'd by
+ *                  coap_delete_resource()@n
+ *
+ *                 COAP_RESOURCE_FLAGS_NOTIFY_CON
+ *                   If this flag is set, coap-observe notifications
+ *                  will be sent confirmable by default.@n
+ *
+ *                 COAP_RESOURCE_FLAGS_NOTIFY_NON (default)
+ *                  If this flag is set, coap-observe notifications
+ *                  will be sent non-confirmable by default.@n
+ *
+ *                  If flags is set to 0 then the
+ *                  COAP_RESOURCE_FLAGS_NOTIFY_NON is considered.
+ * 
+ * @return         A pointer to the new object or @c NULL on error.
  */
 coap_resource_t *coap_resource_init(const unsigned char *uri_path,
                                     size_t len, int flags);