About ast-grep-outline
A skill for using ast-grep outline to create compact structural maps of source code. It helps developers inspect declarations, members, and line numbers before opening relevant code; it shows local syntax without resolving references or building call graphs.
Key features
- 01List top-level declarations and members
- 02Show line numbers and signatures
- 03Filter by exports, imports, or structure
- 04Filter items by name or type
- 05Emit file structure as a JSON stream
Use cases
- 01Review a file structure before editing
- 02Map the public API of an unfamiliar directory
- 03Find a symbol's members and line numbers
- 04Trace dependency direction between files
- 05Review structure in changed files
Install
Copy the command and run it in a terminal.
npx skills add https:/ / github.com/ ast-grep/ agent-skill --skill ast-grep-outlineAfter installing, type/ast-grep-outlinein Claude Code to confirm it loaded.
Details
From the project READMEUse ast-grep outline
ast-grep outline prints a compact structural map of source code with line
numbers: top-level items (imports, functions, classes, structs,
interfaces, modules, enums) and their direct members (fields, methods,
constructors, enum variants). It is a local, syntax-only view — cheap enough
to run before any full file read.
Read code in stages: find candidate files with search or file names, outline them, then open only the source range the outline points to. Defaults adapt to input: a file shows its local structure with member digests; a directory shows only its exported surface as grouped names.
When To Use It
Understand a file before editing. Get a table of contents, dependencies, and public entry points before reading implementation details:
ast-grep outline <file>
ast-grep outline <file> --items imports
ast-grep outline <file> --items exports
Map an unfamiliar directory. Scan the public surface of a subtree, then narrow by symbol type when you know what you are looking for:
ast-grep outline <dir> --items exports
ast-grep outline <dir> --type struct,enum,function
Zoom into a known symbol. After search finds a likely name, list its members with line numbers instead of reading the whole body:
ast-grep outline <file> --match <symbol> --type class --view expanded
Trace dependency direction. Find which files import a package or module to decide where a change belongs:
ast-grep outline <dir> --items imports --view signatures
Review changed files after editing. Git tells you what changed; outline summarizes the resulting structure and public surface:
ast-grep outline $(git diff --name-only HEAD) --items exports
Argument Guide
--items <KIND>selects top-level items:structurefor local declarations (file default),exportsfor public API (directory default),importsfor dependencies,allwhen import/export edges matter together.--view <VIEW>controls detail, from least to most:namesfor directory scans,signaturesfor one line per item,digestfor signatures plus member names,expandedfor one line per member with its line number.--match <REGEX>filters top-level items by name or signature. Rust regex, case-sensitive; it never matches members.--type <TYPE[,TYPE...]>keeps only some top-level symbol types, such as--type class,function. Member types likemethod,fieldnever match top-level items.--pub-membershides private members when the view prints members.--json=streamemits one JSON object per file with precise ranges. Use it only to pipe or post-process entries; prefer text for navigation.
Limits
outline shows local syntax structure. It does not resolve references, infer
types, follow re-export chains, or build a call graph. Use ast-grep run,
rg, or compiler-backed tools for those questions, then outline the candidate
files they surface.