-- this would be the simplest way.
-- else you have to query the dictionaries for all columns associated with a table

-- create a simple sql file a.sql as shown
-- this query lists the tables that start with name TEST
-- i have prompted to show the table name during the execution
-- chr(10) produces a new line
-- simlarly you can do any formatting you want
-- now do a spool to some kinda temp file
-- execute the sql
-- spool off
-- execute the spooled temp file

dbadmin@mutation_mutation > get a
  1  set head off
  2* select 'prompt description of table : '||table_name||chr(10)||'desc '||table_name ||';' from user_tables where table_name like ('TEST%')
dbadmin@mutation_mutation > spool dumm
dbadmin@mutation_mutation > @a

prompt description of table : TEST
desc TEST;

prompt description of table : TEST11
desc TEST11;

prompt description of table : TEST23
desc TEST23;

dbadmin@mutation_mutation > spool off
dbadmin@mutation_mutation > @dumm.lst
SP2-0734: unknown command beginning "dbadmin@mu..." - rest of line ignored.
description of table : TEST
 Name                                                  Null?    Type
 ----------------------------------------------------- -------- ------------------------------------
 ID                                                    NOT NULL NUMBER
 NAME                                                           VARCHAR2(10)

description of table : TEST11
 Name                                                  Null?    Type
 ----------------------------------------------------- -------- ------------------------------------
 ID                                                             VARCHAR2(30)

description of table : TEST23
 Name                                                  Null?    Type
 ----------------------------------------------------- -------- ------------------------------------
 Y                                                              VARCHAR2(300)

SP2-0734: unknown command beginning "dbadmin@mu..." - rest of line ignored.
dbadmin@mutation_mutation >