No they're accurate descriptions. Karifean confirmed it. So we do need to pay attention to them. It is not just flavor text/story purpose.
As for the roles, scruff, Karifean also posted them in the intro thread of what they could possibly be.
Here's the spoiler from the first post.
Here is a list of roles as well as their abilities
Murderer
A Chaos-aligned role. Can kill someone every night. The chosen player is eliminated from the game unless protected by the Protector in the same night. The murderer cannot kill themselves.
Roleblocker
A Chaos-aligned role (in this game at least). Can block the ability of another player every night. Whatever night action the chosen player may have decided to do, it will not go through.
Lackey
A Chaos-aligned role. Can kill someone every night, but only one Lackey may perform a kill per night. If multiple Lackeys decide to do a kill they will all fail, so make sure to communicate. One Lackey being eliminated does not hamper the other Lackeys' ability to kill.
Detective
A Cosmos-aligned role. Can choose someone every night to investigate. The Detective will then be privately informed of the chosen player's alignment.
Protector
A Cosmos-aligned role. Can choose someone every night to protect. The chosen player is immune to being killed by the Murderer or Lackeys for this single night. The same player may be chosen repeatedly, but the Protector cannot protect themselves.
Switcher
Appears on either alignment. Can choose two people every night to switch. Night actions targeting one will target the other instead, and vice versa.
Identifier
Appears on either alignment. Can choose someone every night to investigate. The Identifier will then be privately informed of the chosen player's identity. They will not be informed of their role or ability.
Tracker
Appears on either alignment. Can choose someone every night to track. The Tracker will then be privately informed of who the chosen player used their ability on that night (if anyone). They will not be informed of anything but the chosen player's username.
Watcher
Appears on either alignment. Can choose someone every night to watch. The Watcher will then be privately informed of who used an ability on the chosen player that night. They will not be informed of anything but those players' usernames.
Vanilla
Appears on either alignment. Has no special abilities.
Unless specified otherwise you cannot target yourself with your ability. If you end up targeting yourself anyways due to the Switcher switching you and your intended target, your ability will simply fail.
And what roles will be in this game?
The Chaos side will definitely consist of either one Murderer and a supplementary role or two Lackeys. The supplementary role may be the Roleblocker, but it may also be any of the other 'either alignment' roles in the game.
The Cosmos side will definitely consist of at least a Detective, a Protector and one Vanilla player. The other Cosmos-aligned players may be any role that is not explicitly Chaos-aligned, including more Vanilla players.