diff --git a/things/openapi.yml b/things/openapi.yml
index 2c2cf647..f44afc4d 100644
--- a/things/openapi.yml
+++ b/things/openapi.yml
@@ -35,7 +35,7 @@ paths:
     get:
       summary: Retrieves things
       description: |
-        Retrieves a list of managed things. Due to performance concerns, data
+        Retrieves a list of things. Due to performance concerns, data
         is retrieved in subsets. The API things must ensure that the entire
         dataset is consumed either by making subsequent requests, or by
         increasing the subset size of the initial request.
@@ -202,9 +202,9 @@ paths:
         '500':
           $ref: "#/components/responses/ServiceError"
     get:
-      summary: Retrieves managed channels
+      summary: Retrieves channels
       description: |
-        Retrieves a list of managed channels. Due to performance concerns, data
+        Retrieves a list of channels. Due to performance concerns, data
         is retrieved in subsets. The API things must ensure that the entire
         dataset is consumed either by making subsequent requests, or by
         increasing the subset size of the initial request.
diff --git a/twins/openapi.yml b/twins/openapi.yml
index ccee5dd7..66dc075b 100644
--- a/twins/openapi.yml
+++ b/twins/openapi.yml
@@ -30,9 +30,9 @@ paths:
           $ref: '#/components/responses/ServiceError'
 
     get:
-      summary: Retrieves managed twins
+      summary: Retrieves twins
       description: |
-        Retrieves a list of managed twins. Due to performance concerns, data
+        Retrieves a list of twins. Due to performance concerns, data
         is retrieved in subsets.
       tags:
         - twins
@@ -129,7 +129,6 @@ paths:
         - $ref: '#/components/parameters/Authorization'
         - $ref: '#/components/parameters/Limit'
         - $ref: '#/components/parameters/Offset'
-        - $ref: '#/components/parameters/Metadata'
       responses:
         '200':
           $ref: '#/components/responses/StatesPageRes'
@@ -150,6 +149,7 @@ components:
       in: header
       schema:
         type: string
+        format: uuid
       required: true
     Limit:
       name: limit
@@ -193,6 +193,7 @@ components:
       in: path
       schema:
         type: string
+        format: uuid
         minimum: 1
       required: true
 
@@ -293,6 +294,7 @@ components:
         twin_id:
           type: string
           description: ID of twin state belongs to.
+          format: uuid
         id:
           type: number
           description: State position in a time row of states.