MySQL 9.3 Reference Manual Including MySQL NDB Cluster 9.3
ALTER LIBRARYlibrary_nameCOMMENT "comment_text"
This statement adds a comment to the named JavaScript library, or
replaces the existing comment if there is one. Following execution
of this statement, the updated comment can be viewed in the output
of SHOW CREATE LIBRARY and in the
ROUTINE_COMMENT column of the Information
Schema LIBRARIES table. The comment
text must be quoted.
To remove a comment from a library without replacing it, specify
an empty comment string (COMMENT "" or
COMMENT '').
ALTER LIBRARY was added in MySQL 9.3.0.