CREATE EXTENSION pg_sift;
SELECT amname, amtype FROM pg_am WHERE amname = 'sift';
 amname | amtype 
--------+--------
 sift   | i
(1 row)

SELECT oprnamespace::regnamespace, oprname, oprleft::regtype, oprright::regtype
  FROM pg_operator WHERE oprname = '@@>';
 oprnamespace | oprname | oprleft | oprright 
--------------+---------+---------+----------
 pg_catalog   | @@>     | text    | text
(1 row)

SELECT opcname, opcdefault FROM pg_opclass
  WHERE opcmethod = (SELECT oid FROM pg_am WHERE amname = 'sift');
 opcname  | opcdefault 
----------+------------
 text_ops | t
(1 row)

CREATE TABLE docs (id int, body text);
CREATE INDEX docs_body_sift ON docs USING sift (body) WITH (b = 2);
ERROR:  value 2 out of bounds for option "b"
DETAIL:  Valid values are between "0.000000" and "1.000000".
CREATE INDEX docs_body_sift ON docs USING sift (body) WITH (k1 = 1.5, stemmer = 'english_stem');
SET sift.simd = scalar;
SHOW sift.simd;
 sift.simd 
-----------
 scalar
(1 row)

RESET sift.simd;
DROP TABLE docs;
DROP EXTENSION pg_sift;