What does the cryptic crossword clue "Convenient rewriting of panto (2,3)" mean?

The definition is "Convenient". The wordplay uses an anagram. anagram of PANTO = ON TAP; definition: "Convenient" The answer is On tap.

Convenient rewriting of panto (2,3)

Telegraph Prize Cryptic #3149 | 26 Across | 2022-02-27 flower