diff --git a/src/libs/middlewares/dimensions.js b/src/libs/middlewares/dimensions.js
index 8532425cf107ee9f19b13009cdbbdc365e3ebbc3..618a510e028742dbbf4a8e9ca04d19d936d9e39e 100644
--- a/src/libs/middlewares/dimensions.js
+++ b/src/libs/middlewares/dimensions.js
@@ -12,6 +12,12 @@
 * app.use(dimensions())
 */
 
+/**
+ * This function returns the intersection of two arrays
+ * @param  {array} a [description]
+ * @param  {array} b [description]
+ * @return {array}   [description]
+ */
 function intersect(a, b) {
     let t;
     if (b.length > a.length) {
diff --git a/src/libs/middlewares/query.js b/src/libs/middlewares/query.js
index 7b0cc58682c4ed4bf8946dff8f1c25093b3b0a74..74a0c505cf02285dde3a35c0d0fc6365b8b4ce86 100644
--- a/src/libs/middlewares/query.js
+++ b/src/libs/middlewares/query.js
@@ -2,6 +2,12 @@ const libs = `${process.cwd()}/libs`;
 const log = require(`${libs}/log`)(module);
 const execQuery = require(`${libs}/db/query_exec`);
 
+/**
+ * Middleware that executes a query defined by a squel object in req.sql
+ * @param  {Object}   req  [description]
+ * @param  {Object}   res  [description]
+ * @param  {Function} next [description]
+ */
 function query(req, res, next) {
     log.debug(req.sql);
     execQuery(req.sql.text, req.sql.values).then((result) => {
diff --git a/src/libs/middlewares/response.js b/src/libs/middlewares/response.js
index 09fa56566ec8444056fd3dbf3f8f0447eff9470a..83580825109c37c7da18e08d8c9c28b3e51487ea 100644
--- a/src/libs/middlewares/response.js
+++ b/src/libs/middlewares/response.js
@@ -2,6 +2,10 @@ const libs = `${process.cwd()}/libs`;
 const log = require(`${libs}/log`)(module);
 const xml = require('js2xmlparser');
 
+/**
+ * Custom generic middleware used to send api responses
+ * @param  {string} value text to be used in the xml response
+ */
 function response(value) {
     return (req, res, next) => {
         log.debug(req.query.format);