diff --git a/packages/api/src/shell/dropAllDbObjects.js b/packages/api/src/shell/dropAllDbObjects.js
index fdc3001c1..e6bed8376 100644
--- a/packages/api/src/shell/dropAllDbObjects.js
+++ b/packages/api/src/shell/dropAllDbObjects.js
@@ -5,6 +5,15 @@ const { getLogger, extendDatabaseInfo } = require('dbgate-tools');
 
 const logger = getLogger('dropAllDbObjects');
 
+/**
+ * Drops all database objects
+ * @param {object} options
+ * @param {connectionType} options.connection - connection object
+ * @param {object} options.systemConnection - system connection (result of driver.connect). If not provided, new connection will be created
+ * @param {object} options.driver - driver object. If not provided, it will be loaded from connection
+ * @param {object} options.analysedStructure - analysed structure of the database. If not provided, it will be loaded
+ * @returns {Promise}
+ */
 async function dropAllDbObjects({ connection, systemConnection, driver, analysedStructure }) {
   if (!driver) driver = requireEngineDriver(connection);
 
diff --git a/packages/api/src/shell/executeQuery.js b/packages/api/src/shell/executeQuery.js
index 8dcdc1ab3..a08660144 100644
--- a/packages/api/src/shell/executeQuery.js
+++ b/packages/api/src/shell/executeQuery.js
@@ -8,12 +8,12 @@ const logger = getLogger('execQuery');
 /**
  * Executes SQL query
  * @param {object} options
- * @param {connectionType} options.connection - connection object
- * @param {object} options.systemConnection - system connection (result of driver.connect)
- * @param {object} options.driver - driver object
- * @param {string} options.sql - SQL query
- * @param {string} options.sqlFile - SQL file
- * @param {boolean} options.logScriptItems - whether to log script items instead of whole script
+ * @param {connectionType} [options.connection] - connection object
+ * @param {object} [options.systemConnection] - system connection (result of driver.connect). If not provided, new connection will be created
+ * @param {object} [options.driver] - driver object. If not provided, it will be loaded from connection
+ * @param {string} [options.sql] - SQL query
+ * @param {string} [options.sqlFile] - SQL file
+ * @param {boolean} [options.logScriptItems] - whether to log script items instead of whole script
  */
 async function executeQuery({
   connection = undefined,
diff --git a/packages/api/src/shell/jsonLinesWriter.js b/packages/api/src/shell/jsonLinesWriter.js
index 44c56e8fd..0e12de262 100644
--- a/packages/api/src/shell/jsonLinesWriter.js
+++ b/packages/api/src/shell/jsonLinesWriter.js
@@ -24,6 +24,14 @@ class StringifyStream extends stream.Transform {
   }
 }
 
+/**
+ * Returns writer object for {@link copyStream} function. This writer object writes data to JSONL file. JSONL format - text file, every line is JSON encoded row, used eg. by MongoDB.
+ * @param {object} options
+ * @param {string} options.fileName - file name
+ * @param {string} [options.encoding] - encoding of the file
+ * @param {boolean} [options.header] - whether to write header. Header is JSON describing source table structure. Header is specific to DbGate, if you want eg. to import data to MongoDB, you should not write header.
+ * @returns {Promise<writerType>} - writer object
+ */
 async function jsonLinesWriter({ fileName, encoding = 'utf-8', header = true }) {
   logger.info(`Writing file ${fileName}`);
   const stringify = new StringifyStream({ header });
diff --git a/packages/api/src/shell/jsonReader.js b/packages/api/src/shell/jsonReader.js
index 48423f3ca..2de75930c 100644
--- a/packages/api/src/shell/jsonReader.js
+++ b/packages/api/src/shell/jsonReader.js
@@ -45,6 +45,17 @@ class ParseStream extends stream.Transform {
   }
 }
 
+/**
+ * Creates reader object for JSON file for {@link copyStream} function.
+ * @param {object} options
+ * @param {string} options.fileName - file name or URL
+ * @param {string} options.jsonStyle - 'object' or 'array'
+ * @param {string} [options.keyField] - key field for object style
+ * @param {string} [options.rootField] - root field for object style
+ * @param {string} [options.encoding] - encoding of the file
+ * @param {number} [options.limitRows] - maximum number of rows to read
+ * @returns {Promise<readerType>} - reader object
+ */
 async function jsonReader({
   fileName,
   jsonStyle,
diff --git a/packages/api/src/shell/jsonWriter.js b/packages/api/src/shell/jsonWriter.js
index a0ce19f24..8058cabdb 100644
--- a/packages/api/src/shell/jsonWriter.js
+++ b/packages/api/src/shell/jsonWriter.js
@@ -85,6 +85,16 @@ class StringifyStream extends stream.Transform {
   }
 }
 
+/**
+ * Returns writer object for {@link copyStream} function. This writer object writes data to JSON file.
+ * @param {object} options
+ * @param {string} options.fileName - file name
+ * @param {string} [options.jsonStyle] - 'object' or 'array'
+ * @param {string} [options.keyField] - key field for object style
+ * @param {string} [options.rootField] - root field for object style
+ * @param {string} [options.encoding] - encoding of the file
+ * @returns {Promise<writerType>} - writer object
+ */
 async function jsonWriter({ fileName, jsonStyle, keyField = '_key', rootField, encoding = 'utf-8' }) {
   logger.info(`Writing file ${fileName}`);
   const stringify = new StringifyStream({ jsonStyle, keyField, rootField });
diff --git a/packages/api/src/shell/queryReader.js b/packages/api/src/shell/queryReader.js
index ec1634104..9d8df321c 100644
--- a/packages/api/src/shell/queryReader.js
+++ b/packages/api/src/shell/queryReader.js
@@ -3,6 +3,15 @@ const connectUtility = require('../utility/connectUtility');
 const { getLogger } = require('dbgate-tools');
 const logger = getLogger('queryReader');
 
+/**
+ * Returns reader object for {@link copyStream} function. This reader object reads data from query.
+ * @param {object} options
+ * @param {connectionType} options.connection - connection object
+ * @param {string} options.query - SQL query
+ * @param {string} [options.queryType] - query type
+ * @param {string} [options.sql] - SQL query. obsolete; use query instead
+ * @returns {Promise<readerType>} - reader object
+ */
 async function queryReader({
   connection,
   query,
diff --git a/packages/api/src/shell/tableReader.js b/packages/api/src/shell/tableReader.js
index 373b9ce11..3233419b4 100644
--- a/packages/api/src/shell/tableReader.js
+++ b/packages/api/src/shell/tableReader.js
@@ -7,7 +7,7 @@ const logger = getLogger('tableReader');
  * Creates reader object for {@link copyStream} function. This reader object reads data from table or view.
  * @param {object} options
  * @param {connectionType} options.connection - connection object
- * @param {object} options.systemConnection - system connection (result of driver.connect)
+ * @param {object} options.systemConnection - system connection (result of driver.connect). If not provided, new connection will be created
  * @param {string} options.pureName - table name
  * @param {string} options.schemaName - schema name
  * @returns {Promise<readerType>} - reader object
diff --git a/packages/api/src/shell/tableWriter.js b/packages/api/src/shell/tableWriter.js
index 90a5b579b..80fe5ad4c 100644
--- a/packages/api/src/shell/tableWriter.js
+++ b/packages/api/src/shell/tableWriter.js
@@ -7,10 +7,10 @@ const logger = getLogger('tableWriter');
  * Creates writer object for {@link copyStream} function. This writer object writes data to table. Table could be created if not exists.
  * @param {object} options
  * @param {connectionType} options.connection - connection object
- * @param {object} options.systemConnection - system connection (result of driver.connect)
+ * @param {object} options.systemConnection - system connection (result of driver.connect). If not provided, new connection will be created
+ * @param {object} options.driver - driver object. If not provided, it will be loaded from connection
  * @param {string} options.pureName - table name
  * @param {string} options.schemaName - schema name
- * @param {object} options.driver - driver object
  * @param {boolean} options.dropIfExists - drop table if exists
  * @param {boolean} options.truncate - truncate table before insert
  * @param {boolean} options.createIfNotExists - create table if not exists
diff --git a/packages/api/src/shell/types.js b/packages/api/src/shell/types.js
index ebdc4574d..04e4efedb 100644
--- a/packages/api/src/shell/types.js
+++ b/packages/api/src/shell/types.js
@@ -1,11 +1,11 @@
 /**
- * Reader (input) object for copyStream function
+ * Reader (input) object for {@link copyStream} function
  * @typedef {Object} readerType
  *
  */
 
 /**
- * Writer (output) object for copyStream function
+ * Writer (output) object for {@link copyStream} function
  * @typedef {Object} writerType
  *
  */