ast-observer.md

AST Observer

The AST observer is experimental and off by default.

colab settings experiments set ast-observer true
colab run ast file.py
colab run ast file.jl
colab run ast file.R
colab run ast notebook.ipynb
colab run watch file.py --ast
colab ai code explain file.py
colab ai code deps file.py
colab run script file.py --ast --session work
colab run notebook notebook.ipynb --ast --session work

The observer reads local files only. It does not execute code during parsing and does not send source to an AI model.

Current parser:

• Python files
• Julia files through a basic outline parser
• R files through a basic outline parser
• notebook code cells from .ipynb
• imports
• functions
• classes
• main guard
• top-level calls
• simple shell escape markers
• likely package dependencies from imports

This release uses small local parsers instead of Tree-sitter. Python has the most complete outline. Julia and R support imports/packages and top-level function/module-style markers only. Add Tree-sitter when the AST view needs exact syntax nodes or deeper multi-language support.

JSON output is available with --json and contains no ANSI.