A pointed getter solves a practical validation problem: checking nested data is not enough when an error must identify the field that failed. It behaves like a lens getter but returns both the focused value and its path, allowing validators to build breadcrumbs for precise errors. section 14.2.4
Nested validation with paths
A pointed validator can inspect an outer string field and compose an inner validator through a nested getter. Applying it to Outer "" (Inner 0) produces separate paths such as ["stringField"] and ["innerField", "intField"], rather than undifferentiated failures. Getters may be written manually or generated with Template Haskell. section 14.2.4
