Better wording

api/client-server/definitions/request_token_response.yaml

@@ -16,9 +16,9 @@ properties:
   sid:
     type: string
     description: |-
-      The session ID. Session IDs are opaque strings generated by a server.
+      The session ID. Session IDs are opaque strings that must consist entirely
-      They must consist entirely of the characters ``[0-9a-zA-Z.=_-]``. Their
+      of the characters ``[0-9a-zA-Z.=_-]``. Their length must not exceed 255
-      length must not exceed 255 characters and they must not be empty.
+      characters and they must not be empty.
     example: "123abc"
   submit_url:
     type: string