What expression indicates that something is precisely what one needs?

The expression "Just what the doctor ordered" is commonly used to indicate that something is exactly what someone needs, often in a timely or appropriate manner. This phrase conveys a sense of satisfaction and alignment with what the person was looking for, implying that it fulfills a specific requirement or desire perfectly.

In contrast, "Exactly what was needed" also suggests a fit, but it lacks the idiomatic flair and common usage of the phrase regarding appropriateness. "Taste of his own medicine" refers to someone experiencing the same unpleasantness they have inflicted on others, and "Will cost you an arm and a leg" indicates something that is very expensive, which does not relate to meeting a need. Both of these expressions do not capture the idea of appropriateness or suitability in the same way that "Just what the doctor ordered" does.