does what it says on the tin

Từ điển tiếng Anh - Cambridge Advanced Learners Dictionary

does what it says on the tin idiom UK informal
If something does what it says on the tin, it does exactly what it is intended to do
• The hotel does exactly what it says on the tin and offers customers a relaxing break.
Thesaurus⁺: ↑Efficient and effective
Main entry: say_idiom