Structure of a file or directory from the prebuilt index: every symbol with its line number and one-line signature, NO bodies. For a file, also shows what it imports (with each dependency's main exports) and who imports it. Cheaper than reading the whole file or globbing directories. Use BEFORE reading any file to decide which exact lines you need.

Exact file:line where a function/class/interface/type/const is defined, from the symbol index. Use instead of grepping for definitions. Then read only that line range.

Import graph for one file OR a whole directory/package: what it imports and who imports it. Directory mode aggregates edges (N files -> target). Use for impact analysis before refactoring ("what breaks if I change this package?").

Where a symbol is used: JSX component usages, call sites (with line numbers) and which files import it by name. Use instead of grep-ing for usages. Heuristic — for a common name, narrow with file.

Incremental git-based refresh (only changed files are re-parsed). Rarely needed — tools auto-refresh.