Browser utilities that process your data locally.

No account. No server. No exceptions.

Visual Prompt Constructor

Build structured LLM system prompts with typed blocks. Role, context, constraints, format — composed visually.

CSV & Excel to JSON

Convert CSV and Excel files to precisely typed JSON. Schema control, type enforcement, primary key indexing.

MCP & Skill Generator

Generate production-ready MCP server boilerplate (TypeScript, Python FastMCP) or Claude SKILL.md files.

All processing happens in your browser. Nothing is transmitted to any server. Ever.

Visual Prompt Constructor

Canvas is empty

Tap the Add Block tab above to start building.

1

Load Your File

📂

Drop a file here, or click to browse

Accepts .csv, .xls, and .xlsx  ·  All processing is local

📄
—
—
2

Configure Schema

🗝️ Primary Key / Output Structure Controls top-level JSON shape

Choose a column to index by. Output becomes { "key_value": {row}, … }

☑️ Attribute Selector Uncheck columns to exclude from output
🔢 Type Enforcement Force-cast values per column
Column Sample Value Type Cast
3

JSON Output

Result —

Saved you time? Keep it free.

zerodatatools is free, forever.
1

Describe Your Tool

📋 Context Ingestion Optional — paste API docs or describe intent

📂 Drop a .txt, .md, or .json file for auto-extraction  ·  or skip and type below

or paste text directly
2

Configure Scaffold

🎯 Target Output Format
✏️ Tool / Skill Details
⚙️ Input Parameters
Name Type Description / Notes
3

Generated Scaffold

Output TypeScript

Saved you time? Keep it free.

zerodatatools is free, forever.