What does the cryptic crossword clue "Negotiates to win tip for these servers (10)" mean?

The wordplay uses a charade (building blocks). END (synonym="tip") in BARTERS (synonym="negotiates") = BARTENDERS The answer is BARTENDERS.

Negotiates to win tip for these servers (10)

Guardian Cryptic #29138 | 11 Across | 2023-08-02 flower