diff --git a/src/cmd/openapi.json b/src/cmd/openapi.json
index d3037a89..b08c6a13 100644
--- a/src/cmd/openapi.json
+++ b/src/cmd/openapi.json
@@ -1,6 +1,7 @@
 {
     "openapi": "3.0.0",
     "info": {
+        "title": "Vitastor control API",
         "description": "Vitastor control API",
         "version": "3.0.2",
         "license": {
@@ -11,10 +12,9 @@
         "/status": { "get": {
             "summary": "Show server status",
             "operationId": "status",
-            "produces": [ "application/json" ],
             "parameters": [],
             "responses": {
-                "200": { "content": { "application/json": { "schema": {
+                "200": { "description": "Cluster status", "content": { "application/json": { "schema": {
                     "type": "object",
                     "properties": {
                         "pool_count": { "type": "integer", "format": "uint64", "description": "Total number of pools" },
@@ -60,7 +60,6 @@
         "/image/list": { "get": {
             "summary": "List images",
             "operationId": "imageListGet",
-            "produces": [ "application/json" ],
             "parameters": [ {
                 "name": "params",
                 "in": "query",
@@ -69,23 +68,19 @@
                 "explode": true
             } ],
             "responses": {
-                "200": { "content": { "application/json": { "schema": { "$ref": "#/components/schemas/ImageList" } } } }
+                "200": { "description": "List of images", "content": { "application/json": { "schema": { "$ref": "#/components/schemas/ImageList" } } } }
             }
         }, "post": {
             "summary": "List images",
             "operationId": "imageListPost",
-            "consumes": [ "application/json" ],
-            "produces": [ "application/json" ],
             "requestBody": { "content": { "application/json": { "schema": { "$ref": "#/components/schemas/ImageListParams" } } } },
             "responses": {
-                "200": { "content": { "application/json": { "schema": { "$ref": "#/components/schemas/ImageList" } } } }
+                "200": { "description": "List of images", "content": { "application/json": { "schema": { "$ref": "#/components/schemas/ImageList" } } } }
             }
         } },
         "/image/create": { "post": {
             "summary": "Create an image, snapshot, or a clone",
             "operationId": "imageCreate",
-            "consumes": [ "application/json" ],
-            "produces": [ "application/json" ],
             "requestBody": { "content": { "application/json": { "schema": {
                 "type": "object",
                 "required": [ "image" ],
@@ -113,7 +108,7 @@
                 }
             } } } },
             "responses": {
-                "200": { "content": { "application/json": { "schema": { "$ref": "#/components/schemas/Image" } } } },
+                "200": { "description": "The created image, snapshot or clone", "content": { "application/json": { "schema": { "$ref": "#/components/schemas/Image" } } } },
                 "400": { "$ref": "#/components/responses/Invalid" },
                 "403": { "$ref": "#/components/responses/Forbidden" },
                 "409": { "$ref": "#/components/responses/UpdateConflict" },
@@ -123,8 +118,6 @@
         "/image/modify": { "post": {
             "summary": "Modify an image",
             "operationId": "imageModify",
-            "consumes": [ "application/json" ],
-            "produces": [ "application/json" ],
             "requestBody": { "content": { "application/json": { "schema": {
                 "type": "object",
                 "required": [ "image" ],
@@ -154,7 +147,7 @@
                 }
             } } } },
             "responses": {
-                "200": { "content": { "application/json": { "schema": { "$ref": "#/components/schemas/Image" } } } },
+                "200": { "description": "The modified image", "content": { "application/json": { "schema": { "$ref": "#/components/schemas/Image" } } } },
                 "400": { "$ref": "#/components/responses/Invalid" },
                 "403": { "$ref": "#/components/responses/Forbidden" },
                 "409": { "$ref": "#/components/responses/UpdateConflict" },
@@ -164,8 +157,6 @@
         "/image/delete": { "post": {
             "summary": "Delete image(s)",
             "operationId": "imageDelete",
-            "consumes": [ "application/json" ],
-            "produces": [ "application/json" ],
             "requestBody": { "content": { "application/json": { "schema": {
                 "oneOf": [ {
                     "type": "object",
@@ -195,7 +186,7 @@
                 } ]
             } } } },
             "responses": {
-                "200": { "content": { "application/json": { "schema": {
+                "200": { "description": "Deleted and rebased images", "content": { "application/json": { "schema": {
                     "type": "object",
                     "properties": {
                         "deleted_ids": { "type": "array", "items": { "type": "integer", "format": "uint64" }, "description": "Full inode ID(s) of deleted images" },
@@ -214,17 +205,15 @@
         "/image/flatten": { "post": {
             "summary": "Flatten an image",
             "operationId": "imageFlatten",
-            "consumes": [ "application/json" ],
-            "produces": [ "application/json" ],
             "requestBody": { "content": { "application/json": { "schema": {
                 "type": "object",
-                "required": [ "names" ],
+                "required": [ "image" ],
                 "properties": {
                     "image": { "type": "string", "description": "Image name to flatten" }
                 }
             } } } },
             "responses": {
-                "200": { "content": { "text/plain": { "schema": { "type": "string", "description": "Empty response" } } } },
+                "200": { "description": "Image flattened", "content": { "text/plain": { "schema": { "type": "string", "description": "Empty response" } } } },
                 "400": { "$ref": "#/components/responses/Invalid" },
                 "403": { "$ref": "#/components/responses/Forbidden" },
                 "409": { "$ref": "#/components/responses/UpdateConflict" },
@@ -234,7 +223,6 @@
         "/osd/list": { "get": {
             "summary": "List OSDs",
             "operationId": "osdListGet",
-            "produces": [ "application/json" ],
             "parameters": [ {
                 "name": "params",
                 "in": "query",
@@ -243,24 +231,21 @@
                 "explode": true
             } ],
             "responses": {
-                "200": { "content": { "application/json": { "schema": { "$ref": "#/components/schemas/OsdList" } } } }
+                "200": { "description": "List of OSDs", "content": { "application/json": { "schema": { "$ref": "#/components/schemas/OsdList" } } } }
             }
         }, "post": {
             "summary": "List OSDs",
             "operationId": "osdListPost",
-            "consumes": [ "application/json" ],
-            "produces": [ "application/json" ],
             "requestBody": { "content": { "application/json": { "schema": { "$ref": "#/components/schemas/OsdListParams" } } } },
             "responses": {
-                "200": { "content": { "application/json": { "schema": { "$ref": "#/components/schemas/OsdList" } } } }
+                "200": { "description": "List of OSDs", "content": { "application/json": { "schema": { "$ref": "#/components/schemas/OsdList" } } } }
             }
         } },
         "/osd/alloc": { "post": {
             "summary": "Allocate a new OSD number",
             "operationId": "osdAlloc",
-            "produces": [ "application/json" ],
             "responses": {
-                "200": { "content": { "application/json": { "schema": {
+                "200": { "description": "The allocated OSD number", "content": { "application/json": { "schema": {
                     "type": "integer",
                     "format": "uint64",
                     "description": "New OSD number"
@@ -272,8 +257,6 @@
         "/osd/delete": { "post": {
             "summary": "Delete stopped OSD(s) from etcd",
             "operationId": "osdDelete",
-            "consumes": [ "application/json" ],
-            "produces": [ "application/json" ],
             "requestBody": { "content": { "application/json": { "schema": {
                 "type": "object",
                 "properties": {
@@ -283,7 +266,7 @@
                 }
             } } } },
             "responses": {
-                "200": { "content": { "application/json": { "schema": {
+                "200": { "description": "Deleted OSD numbers", "content": { "application/json": { "schema": {
                     "type": "object",
                     "properties": {
                         "deleted_osds": {
@@ -291,13 +274,11 @@
                             "items": { "type": "integer", "format": "uint64" },
                             "description": "Deleted OSD numbers"
                         }
-                    },
-                    "format": "uint64",
-                    "description": "New OSD number"
+                    }
                 } } } },
                 "400": { "$ref": "#/components/responses/Invalid" },
                 "409": { "$ref": "#/components/responses/UpdateConflict" },
-                "412": { "content": { "application/json": { "schema": {
+                "412": { "description": "Precondition failed: removing these OSD(s) would affect some pools", "content": { "application/json": { "schema": {
                     "type": "object",
                     "properties": {
                         "pool_effects": {
@@ -322,8 +303,6 @@
         "/osd/modify": { "post": {
             "summary": "Modify OSD reweight, tags or noout flag",
             "operationId": "osdModify",
-            "consumes": [ "application/json" ],
-            "produces": [ "application/json" ],
             "requestBody": { "content": { "application/json": { "schema": {
                 "type": "object",
                 "properties": {
@@ -334,15 +313,13 @@
                 }
             } } } },
             "responses": {
-                "200": { "content": { "application/json": { "schema": {
+                "200": { "description": "OSD settings after modification", "content": { "application/json": { "schema": {
                     "type": "object",
                     "properties": {
                         "reweight": { "type": "number", "minimum": 0, "maximum": 1, "description": "OSD weight" },
                         "tags": { "type": "array", "items": { "type": "string" }, "description": "OSD tags" },
                         "noout": { "type": "boolean", "description": "noout flag" }
-                    },
-                    "format": "uint64",
-                    "description": "New OSD number"
+                    }
                 } } } },
                 "400": { "$ref": "#/components/responses/Invalid" },
                 "409": { "$ref": "#/components/responses/UpdateConflict" },
@@ -352,7 +329,6 @@
         "/pool/list": { "get": {
             "summary": "List pools",
             "operationId": "poolListGet",
-            "produces": [ "application/json" ],
             "parameters": [ {
                 "name": "params",
                 "in": "query",
@@ -361,23 +337,19 @@
                 "explode": true
             } ],
             "responses": {
-                "200": { "content": { "application/json": { "schema": { "$ref": "#/components/schemas/PoolList" } } } }
+                "200": { "description": "List of pools", "content": { "application/json": { "schema": { "$ref": "#/components/schemas/PoolList" } } } }
             }
         }, "post": {
             "summary": "List pools",
             "operationId": "poolListPost",
-            "consumes": [ "application/json" ],
-            "produces": [ "application/json" ],
             "requestBody": { "content": { "application/json": { "schema": { "$ref": "#/components/schemas/PoolListParams" } } } },
             "responses": {
-                "200": { "content": { "application/json": { "schema": { "$ref": "#/components/schemas/PoolList" } } } }
+                "200": { "description": "List of pools", "content": { "application/json": { "schema": { "$ref": "#/components/schemas/PoolList" } } } }
             }
         } },
         "/pool/create": { "post": {
             "summary": "Create a pool",
             "operationId": "poolCreate",
-            "consumes": [ "application/json" ],
-            "produces": [ "application/json" ],
             "requestBody": { "content": { "application/json": { "schema": {
                 "allOf": [ {
                     "$ref": "#/components/schemas/PoolConfig"
@@ -387,7 +359,7 @@
                 } } ]
             } } } },
             "responses": {
-                "200": { "content": { "application/json": { "schema": {
+                "200": { "description": "The created pool", "content": { "application/json": { "schema": {
                     "$ref": "#/components/schemas/PoolConfig"
                 } } } },
                 "400": { "$ref": "#/components/responses/Invalid" },
@@ -398,8 +370,6 @@
         "/pool/modify": { "post": {
             "summary": "Modify a pool",
             "operationId": "poolModify",
-            "consumes": [ "application/json" ],
-            "produces": [ "application/json" ],
             "requestBody": { "content": { "application/json": { "schema": {
                 "allOf": [ {
                     "$ref": "#/components/schemas/PoolConfig"
@@ -410,7 +380,7 @@
                 } } ]
             } } } },
             "responses": {
-                "200": { "content": { "application/json": { "schema": {
+                "200": { "description": "The modified pool", "content": { "application/json": { "schema": {
                     "$ref": "#/components/schemas/PoolConfig"
                 } } } },
                 "400": { "$ref": "#/components/responses/Invalid" },
@@ -421,8 +391,6 @@
         "/pool/delete": { "post": {
             "summary": "Delete a pool",
             "operationId": "poolDelete",
-            "consumes": [ "application/json" ],
-            "produces": [ "application/json" ],
             "requestBody": { "content": { "application/json": { "schema": {
                 "type": "object",
                 "properties": {
@@ -432,7 +400,7 @@
                 }
             } } } },
             "responses": {
-                "200": { "content": { "application/json": { "schema": {
+                "200": { "description": "Pool deleted", "content": { "application/json": { "schema": {
                     "type": "object",
                     "properties": { "ok": { "type": "boolean" } }
                 } } } },
@@ -444,7 +412,6 @@
         "/user/list": { "get": {
             "summary": "List users",
             "operationId": "userListGet",
-            "produces": [ "application/json" ],
             "parameters": [ {
                 "name": "params",
                 "in": "query",
@@ -453,26 +420,22 @@
                 "explode": true
             } ],
             "responses": {
-                "200": { "content": { "application/json": { "schema": { "$ref": "#/components/schemas/UserList" } } } }
+                "200": { "description": "List of users", "content": { "application/json": { "schema": { "$ref": "#/components/schemas/UserList" } } } }
             }
         }, "post": {
             "summary": "List users",
             "operationId": "userListPost",
-            "consumes": [ "application/json" ],
-            "produces": [ "application/json" ],
             "requestBody": { "content": { "application/json": { "schema": { "$ref": "#/components/schemas/UserListParams" } } } },
             "responses": {
-                "200": { "content": { "application/json": { "schema": { "$ref": "#/components/schemas/UserList" } } } }
+                "200": { "description": "List of users", "content": { "application/json": { "schema": { "$ref": "#/components/schemas/UserList" } } } }
             }
         } },
         "/user/modify": { "post": {
             "summary": "Modify a user",
             "operationId": "userModify",
-            "consumes": [ "application/json" ],
-            "produces": [ "application/json" ],
             "requestBody": { "content": { "application/json": { "schema": { "$ref": "#/components/schemas/User" } } } },
             "responses": {
-                "200": { "content": { "application/json": { "schema": {
+                "200": { "description": "The modified user", "content": { "application/json": { "schema": {
                     "$ref": "#/components/schemas/User"
                 } } } },
                 "400": { "$ref": "#/components/responses/Invalid" },
@@ -483,8 +446,6 @@
         "/user/delete": { "post": {
             "summary": "Delete a user",
             "operationId": "userDelete",
-            "consumes": [ "application/json" ],
-            "produces": [ "application/json" ],
             "requestBody": { "content": { "application/json": { "schema": {
                 "type": "object",
                 "properties": {
@@ -492,7 +453,7 @@
                 }
             } } } },
             "responses": {
-                "200": { "content": { "application/json": { "schema": {
+                "200": { "description": "User deleted", "content": { "application/json": { "schema": {
                     "type": "object",
                     "properties": { "ok": { "type": "boolean" } }
                 } } } },
@@ -504,7 +465,6 @@
         "/pg/list": { "get": {
             "summary": "List PGs",
             "operationId": "pgListGet",
-            "produces": [ "application/json" ],
             "parameters": [ {
                 "name": "params",
                 "in": "query",
@@ -513,23 +473,19 @@
                 "explode": true
             } ],
             "responses": {
-                "200": { "content": { "application/json": { "schema": { "$ref": "#/components/schemas/PgList" } } } }
+                "200": { "description": "List of PGs", "content": { "application/json": { "schema": { "$ref": "#/components/schemas/PgList" } } } }
             }
         }, "post": {
             "summary": "List PGs",
             "operationId": "pgListPost",
-            "consumes": [ "application/json" ],
-            "produces": [ "application/json" ],
             "requestBody": { "content": { "application/json": { "schema": { "$ref": "#/components/schemas/PgListParams" } } } },
             "responses": {
-                "200": { "content": { "application/json": { "schema": { "$ref": "#/components/schemas/PgList" } } } }
+                "200": { "description": "List of PGs", "content": { "application/json": { "schema": { "$ref": "#/components/schemas/PgList" } } } }
             }
         } },
         "/data/delete": { "post": {
             "summary": "Remove inode data without changing metadata",
             "operationId": "dataDelete",
-            "consumes": [ "application/json" ],
-            "produces": [ "application/json" ],
             "requestBody": { "content": { "application/json": { "schema": {
                 "type": "object",
                 "properties": {
@@ -540,14 +496,14 @@
                 }
             } } } },
             "responses": {
-                "200": { "content": { "application/json": { "schema": {
+                "200": { "description": "Number of removed objects", "content": { "application/json": { "schema": {
                     "type": "object",
                     "properties": {
                         "removed_objects": { "type": "integer", "format": "uint64", "description": "Removed object count" }
                     }
                 } } } },
                 "400": { "$ref": "#/components/responses/Invalid" },
-                "412": { "content": { "application/json": { "schema": {
+                "412": { "description": "Precondition failed: some data could not be removed", "content": { "application/json": { "schema": {
                     "type": "object",
                     "properties": {
                         "total_objects": { "type": "integer", "format": "uint64", "description": "Total object count" },
@@ -570,7 +526,6 @@
         "/data/describe": { "get": {
             "summary": "Describe unclean object locations in the cluster",
             "operationId": "dataDescribeGet",
-            "produces": [ "application/json" ],
             "parameters": [ {
                 "name": "params",
                 "in": "query",
@@ -579,23 +534,19 @@
                 "explode": true
             } ],
             "responses": {
-                "200": { "content": { "application/json": { "schema": { "$ref": "#/components/schemas/DataDescribe" } } } }
+                "200": { "description": "Unclean object locations", "content": { "application/json": { "schema": { "$ref": "#/components/schemas/DataDescribe" } } } }
             }
         }, "post": {
             "summary": "Describe unclean object locations in the cluster",
             "operationId": "dataDescribePost",
-            "consumes": [ "application/json" ],
-            "produces": [ "application/json" ],
             "requestBody": { "content": { "application/json": { "schema": { "$ref": "#/components/schemas/DataDescribeParams" } } } },
             "responses": {
-                "200": { "content": { "application/json": { "schema": { "$ref": "#/components/schemas/DataDescribe" } } } }
+                "200": { "description": "Unclean object locations", "content": { "application/json": { "schema": { "$ref": "#/components/schemas/DataDescribe" } } } }
             }
         } },
         "/data/fix": { "post": {
             "summary": "Fix inconsistent objects in the cluster by deleting some copies",
             "operationId": "dataFix",
-            "consumes": [ "application/json" ],
-            "produces": [ "application/json" ],
             "requestBody": { "content": { "application/json": { "schema": {
                 "type": "object",
                 "properties": {
@@ -619,7 +570,7 @@
                 }
             } } } },
             "responses": {
-                "200": { "content": { "application/json": { "schema": {
+                "200": { "description": "The removed object copy", "content": { "application/json": { "schema": {
                     "type": "object",
                     "properties": {
                         "inode": { "type": "integer", "format": "uint64", "description": "Full inode ID with pool" },
@@ -634,8 +585,6 @@
         "/data/merge": { "post": {
             "summary": "Merge layer data without changing metadata",
             "operationId": "dataMerge",
-            "consumes": [ "application/json" ],
-            "produces": [ "application/json" ],
             "requestBody": { "content": { "application/json": { "schema": {
                 "type": "object",
                 "properties": {
@@ -648,7 +597,7 @@
                 }
             } } } },
             "responses": {
-                "200": { "content": { "application/json": { "schema": {
+                "200": { "description": "The merged layer range", "content": { "application/json": { "schema": {
                     "type": "object",
                     "properties": {
                         "from": { "type": "string", "description": "First merged parent layer" },