vscode-ext-analyze-params

name

vscode-ext-analyze-params

description

Analyze the parameter signature of a specific VSCode extension command by reverse-engineering the minified extension.js source code. Given an extension ID and a command name, extracts the registerCommand callback's formal parameters, infers types from runtime type-checking patterns (typeof, Array.isArray), and checks URI handlers for human-readable parameter names. Use when the user asks: what parameters does a command accept, how to call executeCommand with arguments, what's the signature of a specific extension command, reverse-engineer command parameters. Run list-commands first to discover available commands, then use this skill to deep-dive into specific ones.

Analyze VSCode Extension Command Parameters

Deep-dive into a specific command's parameter signature from minified source code.

Usage

# Analyze a single command
python3 scripts/analyze_params.py <extension-id> <command-name> [--context-size 800]

# Analyze all commands at once
python3 scripts/analyze_params.py <extension-id> --all

What It Does

For each target command:

1. Finds the registerCommand("cmd", callback) in extension.js
2. Extracts the callback parameter list (e.g. (N, v, U))
3. Analyzes type-checking patterns in the function body:
   • typeof X === "string" → parameter is string
   • Array.isArray(X) → parameter is array
   • X?.property → parameter is object
   • Ternary guards like typeof X === "string" ? X : undefined → optional typed parameter
4. Checks URI Handlers (handleUri) for human-readable parameter name mapping
5. Extracts the surrounding code context for manual inspection

How to Read the Output

┌─ claude-vscode.terminal.open
│  Params: (N, v, U)
│  Types:  N: string, v: string[], U: object (via validator)
│  URI:    /open → params: [session, prompt]
│  Mapped: N=prompt, v=flags, U=options (inferred from URI + position)
└──

• Params: Raw minified parameter names from the callback
• Types: Inferred from type guards in the function body
• URI: If the command is also accessible via URI handler, shows the human-readable parameter names
• Context: The surrounding code for manual analysis

Key Insights

1. Parameter position matters — editor.open(session, prompt, viewColumn) puts prompt as arg 2
2. URI Handlers are the Rosetta Stone — they map minified names to human-readable ones
3. Type guards reveal optionality — typeof X === "string" ? X : undefined means the param is optional
4. Validator function calls (e.g., M_6(U)) indicate custom object schemas — check the validator's definition for details