AST Manipulation
Expert skill for abstract syntax tree design, traversal, transformation, and manipulation patterns
Best use case
AST Manipulation is best used when you need a repeatable AI agent workflow instead of a one-off prompt.
Expert skill for abstract syntax tree design, traversal, transformation, and manipulation patterns
Teams using AST Manipulation should expect a more consistent output, faster repeated execution, less prompt rewriting.
When to use this skill
- You want a reusable workflow that can be run more than once with consistent structure.
When not to use this skill
- You only need a quick one-off answer and do not need a reusable workflow.
- You cannot install or maintain the underlying files, dependencies, or repository context.
Installation
Claude Code / Cursor / Codex
Manual Installation
- Download SKILL.md from GitHub
- Place it in
.claude/skills/ast-manipulation/SKILL.mdinside your project - Restart your AI agent — it will auto-discover the skill
How AST Manipulation Compares
| Feature / Agent | AST Manipulation | Standard Approach |
|---|---|---|
| Platform Support | Not specified | Limited / Varies |
| Context Awareness | High | Baseline |
| Installation Complexity | Unknown | N/A |
Frequently Asked Questions
What does this skill do?
Expert skill for abstract syntax tree design, traversal, transformation, and manipulation patterns
Where can I find the source code?
You can find the source code on GitHub using the link provided at the top of the page.
SKILL.md Source
# AST Manipulation Skill
## Overview
Expert skill for abstract syntax tree design, traversal, transformation, and manipulation patterns.
## Capabilities
- Design typed AST node hierarchies
- Implement visitor and transformer patterns
- Build AST rewriting systems
- Implement AST diffing and patching
- Generate AST pretty-printers and formatters
- Support AST serialization (JSON, binary)
- Implement pattern matching on AST structures
- Design span/location tracking systems
## Target Processes
- ast-design.js
- semantic-analysis.js
- ir-design.js
- code-generation-llvm.js
- lsp-server-implementation.js
- macro-system-implementation.js
## Dependencies
None (core skill)
## Usage Guidelines
1. **Node Design**: Design immutable AST nodes with clear ownership semantics
2. **Location Tracking**: Include source spans on all nodes from the beginning
3. **Visitor Pattern**: Implement visitor pattern for extensible traversal
4. **Transformation**: Use transformer pattern for AST-to-AST transformations
5. **Serialization**: Support both human-readable (JSON) and efficient (binary) serialization
## Output Schema
```json
{
"type": "object",
"properties": {
"nodeTypes": {
"type": "array",
"items": {
"type": "object",
"properties": {
"name": { "type": "string" },
"fields": { "type": "array" },
"parent": { "type": "string" }
}
}
},
"visitors": {
"type": "array",
"items": { "type": "string" }
},
"transformers": {
"type": "array",
"items": { "type": "string" }
},
"generatedFiles": {
"type": "array",
"items": { "type": "string" }
}
}
}
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