diff --git a/lib/Chat/ChatManager.php b/lib/Chat/ChatManager.php
index a4e7ee63d55..a43712a88dc 100644
--- a/lib/Chat/ChatManager.php
+++ b/lib/Chat/ChatManager.php
@@ -116,6 +116,7 @@ public function __construct(
 	/**
 	 * Sends a new message to the given chat.
 	 *
+	 * @psalm-param Attendee::ACTOR_* $actorType
 	 * @param bool $shouldSkipLastMessageUpdate If multiple messages will be posted
 	 *             (e.g. when adding multiple users to a room) we can skip the last
 	 *             message and last activity update until the last entry was created
diff --git a/lib/Chat/CommentsManager.php b/lib/Chat/CommentsManager.php
index 4080632d5b3..c79b4822828 100644
--- a/lib/Chat/CommentsManager.php
+++ b/lib/Chat/CommentsManager.php
@@ -25,6 +25,7 @@
 
 use OC\Comments\Comment;
 use OC\Comments\Manager;
+use OCA\Talk\Model\Attendee;
 use OCP\Comments\IComment;
 use OCP\DB\Exception;
 use OCP\DB\QueryBuilder\IQueryBuilder;
@@ -66,7 +67,7 @@ public function getCommentsById(array $ids): array {
 	}
 
 	/**
-	 * @param string $actorType
+	 * @psalm-param Attendee::ACTOR_* $actorType
 	 * @param string $actorId
 	 * @param string[] $messageIds
 	 * @return array
@@ -100,6 +101,7 @@ public function retrieveReactionsByActor(string $actorType, string $actorId, arr
 	 * @param string $objectType Limit the search by object type
 	 * @param string[] $objectIds Limit the search by object ids
 	 * @param string $verb Limit the verb of the comment
+	 * @psalm-param ?Attendee::ACTOR_* $actorType
 	 * @return list<IComment>
 	 */
 	public function searchForObjectsWithFilters(string $search, string $objectType, array $objectIds, string $verb, ?\DateTimeImmutable $since, ?\DateTimeImmutable $until, ?string $actorType, ?string $actorId, int $offset, int $limit = 50): array {
diff --git a/lib/Chat/MessageParser.php b/lib/Chat/MessageParser.php
index 77e42316a9b..9d539d4adb6 100644
--- a/lib/Chat/MessageParser.php
+++ b/lib/Chat/MessageParser.php
@@ -112,6 +112,9 @@ protected function setLastEditInfo(Message $message): void {
 		}
 	}
 
+	/**
+	 * @psalm-param Attendee::ACTOR_* $actorType
+	 */
 	protected function getActorInformation(Message $message, string $actorType, string $actorId, string $displayName = ''): array {
 		if ($actorType === Attendee::ACTOR_USERS) {
 			$tempDisplayName = $this->userManager->getDisplayName($actorId);
diff --git a/lib/Chat/Parser/SystemMessage.php b/lib/Chat/Parser/SystemMessage.php
index 33a38f0d10c..869fc406353 100644
--- a/lib/Chat/Parser/SystemMessage.php
+++ b/lib/Chat/Parser/SystemMessage.php
@@ -843,6 +843,9 @@ protected function getActorFromComment(Room $room, IComment $comment): array {
 		return $this->getActor($room, $comment->getActorType(), $comment->getActorId());
 	}
 
+	/**
+	 * @psalm-param Attendee::ACTOR_* $actorType
+	 */
 	protected function getActor(Room $room, string $actorType, string $actorId): array {
 		if ($actorType === Attendee::ACTOR_GUESTS || $actorType === Attendee::ACTOR_EMAILS) {
 			return $this->getGuest($room, $actorType, $actorId);
diff --git a/lib/Chat/ReactionManager.php b/lib/Chat/ReactionManager.php
index b1f174b6e8e..c439f82e4e3 100644
--- a/lib/Chat/ReactionManager.php
+++ b/lib/Chat/ReactionManager.php
@@ -28,6 +28,7 @@
 use OCA\Talk\Exceptions\ReactionAlreadyExistsException;
 use OCA\Talk\Exceptions\ReactionNotSupportedException;
 use OCA\Talk\Exceptions\ReactionOutOfContextException;
+use OCA\Talk\Model\Attendee;
 use OCA\Talk\Participant;
 use OCA\Talk\ResponseDefinitions;
 use OCA\Talk\Room;
@@ -56,7 +57,7 @@ public function __construct(
 	 * Add reaction
 	 *
 	 * @param Room $chat
-	 * @param string $actorType
+	 * @psalm-param Attendee::ACTOR_* $actorType
 	 * @param string $actorId
 	 * @param integer $messageId
 	 * @param string $reaction
@@ -99,7 +100,7 @@ public function addReactionMessage(Room $chat, string $actorType, string $actorI
 	 * Delete reaction
 	 *
 	 * @param Room $chat
-	 * @param string $actorType
+	 * @psalm-param Attendee::ACTOR_* $actorType
 	 * @param string $actorId
 	 * @param integer $messageId
 	 * @param string $reaction
@@ -159,8 +160,10 @@ public function retrieveReactionMessages(Room $chat, Participant $participant, i
 			$message = $this->messageParser->createMessage($chat, $participant, $comment, $this->l);
 			$this->messageParser->parseMessage($message);
 
+			/** @var Attendee::ACTOR_* $actorType */
+			$actorType = $comment->getActorType();
 			$reactions[$comment->getMessage()][] = [
-				'actorType' => $comment->getActorType(),
+				'actorType' => $actorType,
 				'actorId' => $comment->getActorId(),
 				'actorDisplayName' => $message->getActorDisplayName(),
 				'timestamp' => $comment->getCreationDateTime()->getTimestamp(),
diff --git a/lib/Listener/DisplayNameListener.php b/lib/Listener/DisplayNameListener.php
index 4ab79cb5359..67fa61fee76 100644
--- a/lib/Listener/DisplayNameListener.php
+++ b/lib/Listener/DisplayNameListener.php
@@ -51,6 +51,9 @@ public function handle(Event $event): void {
 		}
 	}
 
+	/**
+	 * @psalm-param Attendee::ACTOR_* $actorType
+	 */
 	protected function updateCachedName(string $actorType, string $actorId, string $newName): void {
 		$this->participantService->updateDisplayNameForActor(
 			$actorType,
diff --git a/lib/Manager.php b/lib/Manager.php
index a3ff4435722..8291e41e242 100644
--- a/lib/Manager.php
+++ b/lib/Manager.php
@@ -318,7 +318,7 @@ public function getRoomsForUser(string $userId, array $sessionIds = [], bool $in
 	}
 
 	/**
-	 * @param string $actorType
+	 * @psalm-param Attendee::ACTOR_* $actorType
 	 * @param string $actorId
 	 * @param array $sessionIds A list of talk sessions to consider for loading (otherwise no session is loaded)
 	 * @param bool $includeLastMessage
diff --git a/lib/Model/Attachment.php b/lib/Model/Attachment.php
index 91aaf2fa24f..04b2fde9d2a 100644
--- a/lib/Model/Attachment.php
+++ b/lib/Model/Attachment.php
@@ -34,8 +34,6 @@
  * @method int getMessageTime()
  * @method void setObjectType(string $objectType)
  * @method string getObjectType()
- * @method void setActorType(string $actorType)
- * @method string getActorType()
  * @method void setActorId(string $actorId)
  * @method string getActorId()
  */
@@ -62,7 +60,10 @@ class Attachment extends Entity {
 	/** @var string */
 	protected $objectType;
 
-	/** @var string */
+	/**
+	 * @var string
+	 * @psalm-var Attendee::ACTOR_*
+	 */
 	protected $actorType;
 
 	/** @var string */
@@ -77,6 +78,20 @@ public function __construct() {
 		$this->addType('actorId', 'string');
 	}
 
+	/**
+	 * @psalm-param Attendee::ACTOR_* $actorType
+	 */
+	public function setActorType(string $actorType): void {
+		$this->actorType = $actorType;
+	}
+
+	/**
+	 * @psalm-return Attendee::ACTOR_*
+	 */
+	public function getActorType(): string {
+		return $this->actorType;
+	}
+
 	/**
 	 * @return array
 	 */
diff --git a/lib/Model/Attendee.php b/lib/Model/Attendee.php
index 8d7ed05788f..f81de9461f7 100644
--- a/lib/Model/Attendee.php
+++ b/lib/Model/Attendee.php
@@ -28,8 +28,6 @@
 /**
  * @method void setRoomId(int $roomId)
  * @method int getRoomId()
- * @method void setActorType(string $actorType)
- * @method string getActorType()
  * @method void setActorId(string $actorId)
  * @method string getActorId()
  * @method void setDisplayName(string $displayName)
@@ -111,7 +109,10 @@ class Attendee extends Entity {
 	/** @var int */
 	protected $roomId;
 
-	/** @var string */
+	/**
+	 * @var string
+	 * @psalm-var Attendee::ACTOR_*
+	 */
 	protected $actorType;
 
 	/** @var string */
@@ -191,6 +192,20 @@ public function __construct() {
 		$this->addType('callId', 'string');
 	}
 
+	/**
+	 * @psalm-param Attendee::ACTOR_* $actorType
+	 */
+	public function setActorType(string $actorType): void {
+		$this->actorType = $actorType;
+	}
+
+	/**
+	 * @psalm-return Attendee::ACTOR_*
+	 */
+	public function getActorType(): string {
+		return $this->actorType;
+	}
+
 	public function getDisplayName(): string {
 		return (string) $this->displayName;
 	}
diff --git a/lib/Model/AttendeeMapper.php b/lib/Model/AttendeeMapper.php
index 268f5eab9f6..3a30714c383 100644
--- a/lib/Model/AttendeeMapper.php
+++ b/lib/Model/AttendeeMapper.php
@@ -46,7 +46,7 @@ public function __construct(IDBConnection $db) {
 
 	/**
 	 * @param int $roomId
-	 * @param string $actorType
+	 * @psalm-param Attendee::ACTOR_* $actorType
 	 * @param string $actorId
 	 * @return Attendee
 	 * @throws DoesNotExistException
diff --git a/lib/Model/Consent.php b/lib/Model/Consent.php
index eef91bceac9..29b5bb45a30 100644
--- a/lib/Model/Consent.php
+++ b/lib/Model/Consent.php
@@ -30,8 +30,6 @@
 /**
  * @method void setToken(string $token)
  * @method string getToken()
- * @method void setActorType(string $actorType)
- * @method string getActorType()
  * @method void setActorId(string $actorId)
  * @method string getActorId()
  * @method void setDateTime(\DateTime $dateTime)
@@ -39,7 +37,10 @@
  */
 class Consent extends Entity implements \JsonSerializable {
 	protected string $token = '';
-	protected string $actorType = '';
+	/**
+	 * @psalm-var Attendee::ACTOR_*
+	 */
+	protected string $actorType;
 	protected string $actorId = '';
 	protected ?\DateTime $dateTime = null;
 
@@ -50,6 +51,20 @@ public function __construct() {
 		$this->addType('dateTime', 'datetime');
 	}
 
+	/**
+	 * @psalm-param Attendee::ACTOR_* $actorType
+	 */
+	public function setActorType(string $actorType): void {
+		$this->actorType = $actorType;
+	}
+
+	/**
+	 * @psalm-return Attendee::ACTOR_*
+	 */
+	public function getActorType(): string {
+		return $this->actorType;
+	}
+
 	public function jsonSerialize(): array {
 		return [
 			'token' => $this->getToken(),
diff --git a/lib/Model/ConsentMapper.php b/lib/Model/ConsentMapper.php
index 7f9f134cabd..863a9b3db3c 100644
--- a/lib/Model/ConsentMapper.php
+++ b/lib/Model/ConsentMapper.php
@@ -63,6 +63,7 @@ public function deleteByToken(string $token): int {
 	}
 
 	/**
+	 * @psalm-param Attendee::ACTOR_* $actorType
 	 * @return Consent[]
 	 */
 	public function findForActor(string $actorType, string $actorId): array {
@@ -75,6 +76,9 @@ public function findForActor(string $actorType, string $actorId): array {
 		return $this->findEntities($query);
 	}
 
+	/**
+	 * @psalm-param Attendee::ACTOR_* $actorType
+	 */
 	public function deleteByActor(string $actorType, string $actorId): int {
 		$query = $this->db->getQueryBuilder();
 		$query->delete($this->getTableName())
@@ -85,6 +89,7 @@ public function deleteByActor(string $actorType, string $actorId): int {
 	}
 
 	/**
+	 * @psalm-param Attendee::ACTOR_* $actorType
 	 * @return Consent[]
 	 */
 	public function findForTokenByActor(string $token, string $actorType, string $actorId): array {
diff --git a/lib/Model/Message.php b/lib/Model/Message.php
index 6ee1f6f6473..c06ef07d8de 100644
--- a/lib/Model/Message.php
+++ b/lib/Model/Message.php
@@ -55,8 +55,11 @@ class Message {
 	/** @var array */
 	protected $parameters = [];
 
-	/** @var string */
-	protected $actorType = '';
+	/**
+	 * @var string
+	 * @psalm-var Attendee::ACTOR_*
+	 */
+	protected $actorType;
 
 	/** @var string */
 	protected $actorId = '';
@@ -148,6 +151,9 @@ public function getMessageType(): string {
 		return $this->type;
 	}
 
+	/**
+	 * @psalm-param Attendee::ACTOR_* $type
+	 */
 	public function setActor(string $type, string $id, string $displayName): void {
 		$this->actorType = $type;
 		$this->actorId = $id;
@@ -161,6 +167,9 @@ public function setLastEdit(string $type, string $id, string $displayName, int $
 		$this->lastEditTimestamp = $timestamp;
 	}
 
+	/**
+	 * @psalm-return Attendee::ACTOR_*
+	 */
 	public function getActorType(): string {
 		return $this->actorType;
 	}
diff --git a/lib/Model/Poll.php b/lib/Model/Poll.php
index c4a1689a004..05f47fbffcc 100644
--- a/lib/Model/Poll.php
+++ b/lib/Model/Poll.php
@@ -40,8 +40,6 @@
  * @method string getVotes()
  * @method void setNumVoters(int $numVoters)
  * @method int getNumVoters()
- * @method void setActorType(string $actorType)
- * @method string getActorType()
  * @method void setActorId(string $actorId)
  * @method string getActorId()
  * @method void setDisplayName(string $displayName)
@@ -67,7 +65,10 @@ class Poll extends Entity {
 	protected string $options = '';
 	protected string $votes = '';
 	protected int $numVoters = 0;
-	protected string $actorType = '';
+	/**
+	 * @psalm-var Attendee::ACTOR_*
+	 */
+	protected string $actorType;
 	protected string $actorId = '';
 	protected ?string $displayName = null;
 	protected int $status = self::STATUS_OPEN;
@@ -88,6 +89,20 @@ public function __construct() {
 		$this->addType('maxVotes', 'int');
 	}
 
+	/**
+	 * @psalm-param Attendee::ACTOR_* $actorType
+	 */
+	public function setActorType(string $actorType): void {
+		$this->actorType = $actorType;
+	}
+
+	/**
+	 * @psalm-return Attendee::ACTOR_*
+	 */
+	public function getActorType(): string {
+		return $this->actorType;
+	}
+
 	/**
 	 * @return TalkPoll
 	 */
diff --git a/lib/Model/ProxyCacheMessages.php b/lib/Model/ProxyCacheMessages.php
index 320852dfa44..47049fa8910 100644
--- a/lib/Model/ProxyCacheMessages.php
+++ b/lib/Model/ProxyCacheMessages.php
@@ -39,8 +39,6 @@
  * @method string getRemoteToken()
  * @method void setRemoteMessageId(int $remoteMessageId)
  * @method int getRemoteMessageId()
- * @method void setActorType(string $actorType)
- * @method string getActorType()
  * @method void setActorId(string $actorId)
  * @method string getActorId()
  * @method void setActorDisplayName(string $actorDisplayName)
@@ -62,7 +60,10 @@ class ProxyCacheMessages extends Entity implements \JsonSerializable {
 	protected string $remoteServerUrl = '';
 	protected string $remoteToken = '';
 	protected int $remoteMessageId = 0;
-	protected string $actorType = '';
+	/**
+	 * @psalm-var Attendee::ACTOR_*
+	 */
+	protected string $actorType;
 	protected string $actorId = '';
 	protected ?string $actorDisplayName = null;
 	/**
@@ -104,6 +105,20 @@ public function getMessageType(): string {
 		return $this->messageType;
 	}
 
+	/**
+	 * @psalm-param Attendee::ACTOR_* $actorType
+	 */
+	public function setActorType(string $actorType): void {
+		$this->actorType = $actorType;
+	}
+
+	/**
+	 * @psalm-return Attendee::ACTOR_*
+	 */
+	public function getActorType(): string {
+		return $this->actorType;
+	}
+
 	/**
 	 * @return TalkRoomProxyMessage
 	 */
diff --git a/lib/Model/Vote.php b/lib/Model/Vote.php
index d2c48480a76..da3e9f5979a 100644
--- a/lib/Model/Vote.php
+++ b/lib/Model/Vote.php
@@ -35,8 +35,6 @@
  * @method int getPollId()
  * @method void setRoomId(int $roomId)
  * @method int getRoomId()
- * @method void setActorType(string $actorType)
- * @method string getActorType()
  * @method void setActorId(string $actorId)
  * @method string getActorId()
  * @method void setDisplayName(string $displayName)
@@ -49,7 +47,10 @@
 class Vote extends Entity {
 	protected int $pollId = 0;
 	protected int $roomId = 0;
-	protected string $actorType = '';
+	/**
+	 * @psalm-var Attendee::ACTOR_*
+	 */
+	protected string $actorType;
 	protected string $actorId = '';
 	protected ?string $displayName = null;
 	protected ?int $optionId = null;
@@ -63,6 +64,20 @@ public function __construct() {
 		$this->addType('optionId', 'int');
 	}
 
+	/**
+	 * @psalm-param Attendee::ACTOR_* $actorType
+	 */
+	public function setActorType(string $actorType): void {
+		$this->actorType = $actorType;
+	}
+
+	/**
+	 * @psalm-return Attendee::ACTOR_*
+	 */
+	public function getActorType(): string {
+		return $this->actorType;
+	}
+
 	/**
 	 * @return TalkPollVote
 	 */
diff --git a/lib/Model/VoteMapper.php b/lib/Model/VoteMapper.php
index cc76c381db7..7eb3396ef91 100644
--- a/lib/Model/VoteMapper.php
+++ b/lib/Model/VoteMapper.php
@@ -56,7 +56,7 @@ public function findByPollId(int $pollId): array {
 
 	/**
 	 * @param int $pollId
-	 * @param string $actorType
+	 * @psalm-param Attendee::ACTOR_* $actorType
 	 * @param string $actorId
 	 * @return Vote[]
 	 */
@@ -89,6 +89,9 @@ public function deleteByPollId(int $pollId): void {
 		$query->executeStatement();
 	}
 
+	/**
+	 * @psalm-param Attendee::ACTOR_* $actorType
+	 */
 	public function deleteVotesByActor(int $pollId, string $actorType, string $actorId): void {
 		$query = $this->db->getQueryBuilder();
 
diff --git a/lib/ResponseDefinitions.php b/lib/ResponseDefinitions.php
index 79797110bf3..dda5dd85b3b 100644
--- a/lib/ResponseDefinitions.php
+++ b/lib/ResponseDefinitions.php
@@ -47,9 +47,11 @@
  *     secret: string,
  * }
  *
+ * @psalm-type TalkActorType = 'bot-'|'bots'|'bridged'|'changelog'|'circles'|'cli'|'emails'|'federated_users'|'groups'|'guests'|'phones'|'system'|'users'
+ *
  * @psalm-type TalkCallPeer = array{
  *     actorId: string,
- *     actorType: string,
+ *     actorType: TalkActorType,
  *     displayName: string,
  *     lastPing: int,
  *     sessionId: string,
@@ -72,7 +74,7 @@
  * @psalm-type TalkChatMessage = array{
  *     actorDisplayName: string,
  *     actorId: string,
- *     actorType: string,
+ *     actorType: TalkActorType,
  *     deleted?: true,
  *     expirationTimestamp: int,
  *     id: int,
@@ -96,7 +98,7 @@
  * @psalm-type TalkRoomProxyMessage = array{
  *     actorDisplayName: string,
  *     actorId: string,
- *     actorType: string,
+ *     actorType: TalkActorType,
  *     expirationTimestamp: int,
  *     message: string,
  *     messageParameters: array<string, array<string, mixed>>,
@@ -147,7 +149,7 @@
  *
  * @psalm-type TalkParticipant = array{
  *     actorId: string,
- *     actorType: string,
+ *     actorType: TalkActorType,
  *     attendeeId: int,
  *     attendeePermissions: int,
  *     attendeePin: string,
@@ -169,14 +171,14 @@
  * @psalm-type TalkPollVote = array{
  *     actorDisplayName: string,
  *     actorId: string,
- *     actorType: string,
+ *     actorType: TalkActorType,
  *     optionId: int,
  *  }
  *
  * @psalm-type TalkPoll = array{
  *     actorDisplayName: string,
  *     actorId: string,
- *     actorType: string,
+ *     actorType: TalkActorType,
  *     details?: TalkPollVote[],
  *     id: int,
  *     maxVotes: int,
@@ -192,13 +194,13 @@
  * @psalm-type TalkReaction = array{
  *     actorDisplayName: string,
  *     actorId: string,
- *     actorType: string,
+ *     actorType: TalkActorType,
  *     timestamp: int,
  * }
  *
  * @psalm-type TalkRoom = array{
  *     actorId: string,
- *     actorType: string,
+ *     actorType: TalkActorType|'',
  *     attendeeId: int,
  *     attendeePermissions: int,
  *     attendeePin: ?string,
diff --git a/lib/Service/BreakoutRoomService.php b/lib/Service/BreakoutRoomService.php
index 238b6120313..5cb2d363ebb 100644
--- a/lib/Service/BreakoutRoomService.php
+++ b/lib/Service/BreakoutRoomService.php
@@ -556,7 +556,7 @@ public function getBreakoutRooms(Room $parent, Participant $participant): array
 
 	/**
 	 * @param Room $parent
-	 * @param string $actorType
+	 * @psalm-param Attendee::ACTOR_* $actorType
 	 * @param string $actorId
 	 * @param bool $throwOnModerator
 	 * @return void
diff --git a/lib/Service/ConsentService.php b/lib/Service/ConsentService.php
index 4d4f8a50ba6..61309ee5bc2 100644
--- a/lib/Service/ConsentService.php
+++ b/lib/Service/ConsentService.php
@@ -39,6 +39,9 @@ public function __construct(
 	) {
 	}
 
+	/**
+	 * @psalm-param Attendee::ACTOR_* $actorType
+	 */
 	public function storeConsent(Room $room, string $actorType, string $actorId): Consent {
 		$consent = new Consent();
 		$consent->setToken($room->getToken());
diff --git a/lib/Service/ParticipantService.php b/lib/Service/ParticipantService.php
index 7ea81e69c7e..d6bac38f61a 100644
--- a/lib/Service/ParticipantService.php
+++ b/lib/Service/ParticipantService.php
@@ -364,6 +364,7 @@ public function joinRoom(RoomService $roomService, Room $room, IUser $user, stri
 	}
 
 	/**
+	 * @psalm-param Attendee::ACTOR_* $actorType
 	 * @throws UnauthorizedException
 	 */
 	public function joinRoomAsFederatedUser(Room $room, string $actorType, string $actorId): Participant {
diff --git a/lib/Service/PollService.php b/lib/Service/PollService.php
index b4eaab223ad..8031c460467 100644
--- a/lib/Service/PollService.php
+++ b/lib/Service/PollService.php
@@ -26,6 +26,7 @@
 namespace OCA\Talk\Service;
 
 use OCA\Talk\Exceptions\WrongPermissionsException;
+use OCA\Talk\Model\Attendee;
 use OCA\Talk\Model\Poll;
 use OCA\Talk\Model\PollMapper;
 use OCA\Talk\Model\Vote;
@@ -46,6 +47,9 @@ public function __construct(
 	) {
 	}
 
+	/**
+	 * @psalm-param Attendee::ACTOR_* $actorType
+	 */
 	public function createPoll(int $roomId, string $actorType, string $actorId, string $displayName, string $question, array $options, int $resultMode, int $maxVotes): Poll {
 		$question = trim($question);
 
diff --git a/openapi-backend-sipbridge.json b/openapi-backend-sipbridge.json
index 7930d2d4aa4..1f613f4c442 100644
--- a/openapi-backend-sipbridge.json
+++ b/openapi-backend-sipbridge.json
@@ -20,6 +20,24 @@
             }
         },
         "schemas": {
+            "ActorType": {
+                "type": "string",
+                "enum": [
+                    "bot-",
+                    "bots",
+                    "bridged",
+                    "changelog",
+                    "circles",
+                    "cli",
+                    "emails",
+                    "federated_users",
+                    "groups",
+                    "guests",
+                    "phones",
+                    "system",
+                    "users"
+                ]
+            },
             "Capabilities": {
                 "type": "object",
                 "required": [
@@ -211,7 +229,7 @@
                         "type": "string"
                     },
                     "actorType": {
-                        "type": "string"
+                        "$ref": "#/components/schemas/ActorType"
                     },
                     "deleted": {
                         "type": "boolean",
@@ -403,7 +421,14 @@
                         "type": "string"
                     },
                     "actorType": {
-                        "type": "string"
+                        "oneOf": [
+                            {
+                                "$ref": "#/components/schemas/ActorType"
+                            },
+                            {
+                                "type": "string"
+                            }
+                        ]
                     },
                     "attendeeId": {
                         "type": "integer",
@@ -634,7 +659,7 @@
                         "type": "string"
                     },
                     "actorType": {
-                        "type": "string"
+                        "$ref": "#/components/schemas/ActorType"
                     },
                     "expirationTimestamp": {
                         "type": "integer",
diff --git a/openapi-federation.json b/openapi-federation.json
index 33c6d5ab033..18eaaa65f82 100644
--- a/openapi-federation.json
+++ b/openapi-federation.json
@@ -20,6 +20,24 @@
             }
         },
         "schemas": {
+            "ActorType": {
+                "type": "string",
+                "enum": [
+                    "bot-",
+                    "bots",
+                    "bridged",
+                    "changelog",
+                    "circles",
+                    "cli",
+                    "emails",
+                    "federated_users",
+                    "groups",
+                    "guests",
+                    "phones",
+                    "system",
+                    "users"
+                ]
+            },
             "Capabilities": {
                 "type": "object",
                 "required": [
@@ -211,7 +229,7 @@
                         "type": "string"
                     },
                     "actorType": {
-                        "type": "string"
+                        "$ref": "#/components/schemas/ActorType"
                     },
                     "deleted": {
                         "type": "boolean",
@@ -462,7 +480,14 @@
                         "type": "string"
                     },
                     "actorType": {
-                        "type": "string"
+                        "oneOf": [
+                            {
+                                "$ref": "#/components/schemas/ActorType"
+                            },
+                            {
+                                "type": "string"
+                            }
+                        ]
                     },
                     "attendeeId": {
                         "type": "integer",
@@ -693,7 +718,7 @@
                         "type": "string"
                     },
                     "actorType": {
-                        "type": "string"
+                        "$ref": "#/components/schemas/ActorType"
                     },
                     "expirationTimestamp": {
                         "type": "integer",
diff --git a/openapi-full.json b/openapi-full.json
index fefb1479618..3834a923a69 100644
--- a/openapi-full.json
+++ b/openapi-full.json
@@ -20,6 +20,24 @@
             }
         },
         "schemas": {
+            "ActorType": {
+                "type": "string",
+                "enum": [
+                    "bot-",
+                    "bots",
+                    "bridged",
+                    "changelog",
+                    "circles",
+                    "cli",
+                    "emails",
+                    "federated_users",
+                    "groups",
+                    "guests",
+                    "phones",
+                    "system",
+                    "users"
+                ]
+            },
             "Bot": {
                 "type": "object",
                 "required": [
@@ -120,7 +138,7 @@
                         "type": "string"
                     },
                     "actorType": {
-                        "type": "string"
+                        "$ref": "#/components/schemas/ActorType"
                     },
                     "displayName": {
                         "type": "string"
@@ -372,7 +390,7 @@
                         "type": "string"
                     },
                     "actorType": {
-                        "type": "string"
+                        "$ref": "#/components/schemas/ActorType"
                     },
                     "deleted": {
                         "type": "boolean",
@@ -660,7 +678,7 @@
                         "type": "string"
                     },
                     "actorType": {
-                        "type": "string"
+                        "$ref": "#/components/schemas/ActorType"
                     },
                     "attendeeId": {
                         "type": "integer",
@@ -748,7 +766,7 @@
                         "type": "string"
                     },
                     "actorType": {
-                        "type": "string"
+                        "$ref": "#/components/schemas/ActorType"
                     },
                     "details": {
                         "type": "array",
@@ -817,7 +835,7 @@
                         "type": "string"
                     },
                     "actorType": {
-                        "type": "string"
+                        "$ref": "#/components/schemas/ActorType"
                     },
                     "optionId": {
                         "type": "integer",
@@ -860,7 +878,7 @@
                         "type": "string"
                     },
                     "actorType": {
-                        "type": "string"
+                        "$ref": "#/components/schemas/ActorType"
                     },
                     "timestamp": {
                         "type": "integer",
@@ -927,7 +945,14 @@
                         "type": "string"
                     },
                     "actorType": {
-                        "type": "string"
+                        "oneOf": [
+                            {
+                                "$ref": "#/components/schemas/ActorType"
+                            },
+                            {
+                                "type": "string"
+                            }
+                        ]
                     },
                     "attendeeId": {
                         "type": "integer",
@@ -1158,7 +1183,7 @@
                         "type": "string"
                     },
                     "actorType": {
-                        "type": "string"
+                        "$ref": "#/components/schemas/ActorType"
                     },
                     "expirationTimestamp": {
                         "type": "integer",
diff --git a/openapi.json b/openapi.json
index ec144d48db0..cf5831f7055 100644
--- a/openapi.json
+++ b/openapi.json
@@ -20,6 +20,24 @@
             }
         },
         "schemas": {
+            "ActorType": {
+                "type": "string",
+                "enum": [
+                    "bot-",
+                    "bots",
+                    "bridged",
+                    "changelog",
+                    "circles",
+                    "cli",
+                    "emails",
+                    "federated_users",
+                    "groups",
+                    "guests",
+                    "phones",
+                    "system",
+                    "users"
+                ]
+            },
             "Bot": {
                 "type": "object",
                 "required": [
@@ -61,7 +79,7 @@
                         "type": "string"
                     },
                     "actorType": {
-                        "type": "string"
+                        "$ref": "#/components/schemas/ActorType"
                     },
                     "displayName": {
                         "type": "string"
@@ -313,7 +331,7 @@
                         "type": "string"
                     },
                     "actorType": {
-                        "type": "string"
+                        "$ref": "#/components/schemas/ActorType"
                     },
                     "deleted": {
                         "type": "boolean",
@@ -542,7 +560,7 @@
                         "type": "string"
                     },
                     "actorType": {
-                        "type": "string"
+                        "$ref": "#/components/schemas/ActorType"
                     },
                     "attendeeId": {
                         "type": "integer",
@@ -630,7 +648,7 @@
                         "type": "string"
                     },
                     "actorType": {
-                        "type": "string"
+                        "$ref": "#/components/schemas/ActorType"
                     },
                     "details": {
                         "type": "array",
@@ -699,7 +717,7 @@
                         "type": "string"
                     },
                     "actorType": {
-                        "type": "string"
+                        "$ref": "#/components/schemas/ActorType"
                     },
                     "optionId": {
                         "type": "integer",
@@ -742,7 +760,7 @@
                         "type": "string"
                     },
                     "actorType": {
-                        "type": "string"
+                        "$ref": "#/components/schemas/ActorType"
                     },
                     "timestamp": {
                         "type": "integer",
@@ -809,7 +827,14 @@
                         "type": "string"
                     },
                     "actorType": {
-                        "type": "string"
+                        "oneOf": [
+                            {
+                                "$ref": "#/components/schemas/ActorType"
+                            },
+                            {
+                                "type": "string"
+                            }
+                        ]
                     },
                     "attendeeId": {
                         "type": "integer",
@@ -1040,7 +1065,7 @@
                         "type": "string"
                     },
                     "actorType": {
-                        "type": "string"
+                        "$ref": "#/components/schemas/ActorType"
                     },
                     "expirationTimestamp": {
                         "type": "integer",
diff --git a/src/types/openapi/openapi-backend-sipbridge.ts b/src/types/openapi/openapi-backend-sipbridge.ts
index fa76de64a99..f6490280395 100644
--- a/src/types/openapi/openapi-backend-sipbridge.ts
+++ b/src/types/openapi/openapi-backend-sipbridge.ts
@@ -40,6 +40,8 @@ export type webhooks = Record<string, never>;
 
 export type components = {
   schemas: {
+    /** @enum {string} */
+    ActorType: "bot-" | "bots" | "bridged" | "changelog" | "circles" | "cli" | "emails" | "federated_users" | "groups" | "guests" | "phones" | "system" | "users";
     Capabilities: {
       features: string[];
       config: {
@@ -87,7 +89,7 @@ export type components = {
     ChatMessage: {
       actorDisplayName: string;
       actorId: string;
-      actorType: string;
+      actorType: components["schemas"]["ActorType"];
       /** @enum {boolean} */
       deleted?: true;
       /** Format: int64 */
@@ -132,7 +134,7 @@ export type components = {
     }, unknown[]]>;
     Room: {
       actorId: string;
-      actorType: string;
+      actorType: components["schemas"]["ActorType"] | string;
       /** Format: int64 */
       attendeeId: number;
       /** Format: int64 */
@@ -219,7 +221,7 @@ export type components = {
     RoomProxyMessage: {
       actorDisplayName: string;
       actorId: string;
-      actorType: string;
+      actorType: components["schemas"]["ActorType"];
       /** Format: int64 */
       expirationTimestamp: number;
       message: string;
diff --git a/src/types/openapi/openapi-federation.ts b/src/types/openapi/openapi-federation.ts
index 5c27c9a577a..2f227d10392 100644
--- a/src/types/openapi/openapi-federation.ts
+++ b/src/types/openapi/openapi-federation.ts
@@ -35,6 +35,8 @@ export type webhooks = Record<string, never>;
 
 export type components = {
   schemas: {
+    /** @enum {string} */
+    ActorType: "bot-" | "bots" | "bridged" | "changelog" | "circles" | "cli" | "emails" | "federated_users" | "groups" | "guests" | "phones" | "system" | "users";
     Capabilities: {
       features: string[];
       config: {
@@ -82,7 +84,7 @@ export type components = {
     ChatMessage: {
       actorDisplayName: string;
       actorId: string;
-      actorType: string;
+      actorType: components["schemas"]["ActorType"];
       /** @enum {boolean} */
       deleted?: true;
       /** Format: int64 */
@@ -145,7 +147,7 @@ export type components = {
     }, unknown[]]>;
     Room: {
       actorId: string;
-      actorType: string;
+      actorType: components["schemas"]["ActorType"] | string;
       /** Format: int64 */
       attendeeId: number;
       /** Format: int64 */
@@ -232,7 +234,7 @@ export type components = {
     RoomProxyMessage: {
       actorDisplayName: string;
       actorId: string;
-      actorType: string;
+      actorType: components["schemas"]["ActorType"];
       /** Format: int64 */
       expirationTimestamp: number;
       message: string;
diff --git a/src/types/openapi/openapi-full.ts b/src/types/openapi/openapi-full.ts
index 471a0a0c1cf..2dc51a755db 100644
--- a/src/types/openapi/openapi-full.ts
+++ b/src/types/openapi/openapi-full.ts
@@ -509,6 +509,8 @@ export type webhooks = Record<string, never>;
 
 export type components = {
   schemas: {
+    /** @enum {string} */
+    ActorType: "bot-" | "bots" | "bridged" | "changelog" | "circles" | "cli" | "emails" | "federated_users" | "groups" | "guests" | "phones" | "system" | "users";
     Bot: {
       description: string | null;
       /** Format: int64 */
@@ -533,7 +535,7 @@ export type components = {
     };
     CallPeer: {
       actorId: string;
-      actorType: string;
+      actorType: components["schemas"]["ActorType"];
       displayName: string;
       /** Format: int64 */
       lastPing: number;
@@ -598,7 +600,7 @@ export type components = {
     ChatMessage: {
       actorDisplayName: string;
       actorId: string;
-      actorType: string;
+      actorType: components["schemas"]["ActorType"];
       /** @enum {boolean} */
       deleted?: true;
       /** Format: int64 */
@@ -683,7 +685,7 @@ export type components = {
     };
     Participant: {
       actorId: string;
-      actorType: string;
+      actorType: components["schemas"]["ActorType"];
       /** Format: int64 */
       attendeeId: number;
       /** Format: int64 */
@@ -711,7 +713,7 @@ export type components = {
     Poll: {
       actorDisplayName: string;
       actorId: string;
-      actorType: string;
+      actorType: components["schemas"]["ActorType"];
       details?: components["schemas"]["PollVote"][];
       /** Format: int64 */
       id: number;
@@ -733,7 +735,7 @@ export type components = {
     PollVote: {
       actorDisplayName: string;
       actorId: string;
-      actorType: string;
+      actorType: components["schemas"]["ActorType"];
       /** Format: int64 */
       optionId: number;
     };
@@ -743,13 +745,13 @@ export type components = {
     Reaction: {
       actorDisplayName: string;
       actorId: string;
-      actorType: string;
+      actorType: components["schemas"]["ActorType"];
       /** Format: int64 */
       timestamp: number;
     };
     Room: {
       actorId: string;
-      actorType: string;
+      actorType: components["schemas"]["ActorType"] | string;
       /** Format: int64 */
       attendeeId: number;
       /** Format: int64 */
@@ -836,7 +838,7 @@ export type components = {
     RoomProxyMessage: {
       actorDisplayName: string;
       actorId: string;
-      actorType: string;
+      actorType: components["schemas"]["ActorType"];
       /** Format: int64 */
       expirationTimestamp: number;
       message: string;
diff --git a/src/types/openapi/openapi.ts b/src/types/openapi/openapi.ts
index 5a444b33e0d..dafa86b5525 100644
--- a/src/types/openapi/openapi.ts
+++ b/src/types/openapi/openapi.ts
@@ -382,6 +382,8 @@ export type webhooks = Record<string, never>;
 
 export type components = {
   schemas: {
+    /** @enum {string} */
+    ActorType: "bot-" | "bots" | "bridged" | "changelog" | "circles" | "cli" | "emails" | "federated_users" | "groups" | "guests" | "phones" | "system" | "users";
     Bot: {
       description: string | null;
       /** Format: int64 */
@@ -392,7 +394,7 @@ export type components = {
     };
     CallPeer: {
       actorId: string;
-      actorType: string;
+      actorType: components["schemas"]["ActorType"];
       displayName: string;
       /** Format: int64 */
       lastPing: number;
@@ -457,7 +459,7 @@ export type components = {
     ChatMessage: {
       actorDisplayName: string;
       actorId: string;
-      actorType: string;
+      actorType: components["schemas"]["ActorType"];
       /** @enum {boolean} */
       deleted?: true;
       /** Format: int64 */
@@ -524,7 +526,7 @@ export type components = {
     };
     Participant: {
       actorId: string;
-      actorType: string;
+      actorType: components["schemas"]["ActorType"];
       /** Format: int64 */
       attendeeId: number;
       /** Format: int64 */
@@ -552,7 +554,7 @@ export type components = {
     Poll: {
       actorDisplayName: string;
       actorId: string;
-      actorType: string;
+      actorType: components["schemas"]["ActorType"];
       details?: components["schemas"]["PollVote"][];
       /** Format: int64 */
       id: number;
@@ -574,7 +576,7 @@ export type components = {
     PollVote: {
       actorDisplayName: string;
       actorId: string;
-      actorType: string;
+      actorType: components["schemas"]["ActorType"];
       /** Format: int64 */
       optionId: number;
     };
@@ -584,13 +586,13 @@ export type components = {
     Reaction: {
       actorDisplayName: string;
       actorId: string;
-      actorType: string;
+      actorType: components["schemas"]["ActorType"];
       /** Format: int64 */
       timestamp: number;
     };
     Room: {
       actorId: string;
-      actorType: string;
+      actorType: components["schemas"]["ActorType"] | string;
       /** Format: int64 */
       attendeeId: number;
       /** Format: int64 */
@@ -677,7 +679,7 @@ export type components = {
     RoomProxyMessage: {
       actorDisplayName: string;
       actorId: string;
-      actorType: string;
+      actorType: components["schemas"]["ActorType"];
       /** Format: int64 */
       expirationTimestamp: number;
       message: string;