Unfamiliar syntax - Query with Parameters in Braces at the beggining
You are right, the (@be int) shown applies to parameterized queries. Applications often parameterize the queries using sp_executesql, and then sent them to the sql server. 

The query will be cached as (variables)QueryText
. And ofcourse, the values won't be cached in the text, since the query is parameterized. 

Parameterized query example

Test Data

CREATE SCHEMA PERSON;

CREATE TABLE Person.Person( BusinessEntityID int );

INSERT INTO Person.Person(BusinessEntityID)
VALUES(1),(2),(3);


Query

exec sp_executesql N'SELECT  * FROM    Person.Person WHERE   BusinessEntityID = @be',N'@be int',@be=2


See the result in the cache with this query

select text from sys.dm_exec_query_stats
cross apply sys.dm_exec_sql_text(sql_handle)
where text like '%Person%';




or

(@be int)SELECT  * FROM    Person.Person WHERE   BusinessEntityID = @be


With a procedure the caching will be different

Create the procedure

use test 
go
create procedure dbo.myproc @dbname varchar(255)
as
select * from sys.databases where name = @dbname 


Run the proc 

exec dbo.myproc @dbname= 'master';


Result in cache

select text from sys.dm_exec_query_stats
cross apply sys.dm_exec_sql_text(sql_handle)
where text like '%myproc%';




or

create procedure dbo.myproc @dbname varchar(255)  as  select * from sys.databases where name = @dbname 


This can also happen when forced parameterization is enabled

Enable forced parameterization

ALTER DATABASE test SET PARAMETERIZATION FORCED


Same query, without parameters

SELECT  *
FROM    Person.Person
WHERE   BusinessEntityID = 5


Result in cache

select text from sys.dm_exec_query_stats
cross apply sys.dm_exec_sql_text(sql_handle)
where text like '%Person%'



or

(@0 int)select * from Person . Person where BusinessEntityID = @0