The privacy-first developer utility suite & scratchpad with zero server transmission.
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The premier 100% offline builder to configure, audit, and export production-grade steering instructions for Claude Code (SKILL.md), Cursor IDE (.cursor/rules/*.mdc), Anthropic (CLAUDE.md), and Multi-Agent frameworks (AGENTS.md).
| Format | Target Platform | Output Directory | Description |
|---|---|---|---|
SKILL.md |
Claude Code & Agentic CLI | .claude/skills/<name>/SKILL.md |
Packaged modular skills with YAML frontmatter and dynamic context loading. |
.mdc |
Cursor IDE (Modern Standard) | .cursor/rules/<name>.mdc |
Modular Cursor rulebooks scoped with globs and alwaysApply flags. |
CLAUDE.md |
Anthropic Root Guidelines | /CLAUDE.md |
Repository-wide instructions using token-dense semantic XML tags. |
AGENTS.md |
Multi-Agent Frameworks | /AGENTS.md |
Demarcated rule blocks for Antigravity, CrewAI, and AutoGen systems. |
claude.json |
MCP Runtime | ~/.claude.json |
Executable commands and environment bindings for Model Context Protocol servers. |
- 📦 Manifest Auto-Detection: Drop your
package.json,Cargo.toml,pyproject.toml, orgo.modto auto-detect your stack and generate tailored rules in seconds. - 🩺 Static Analysis Audit Panel: Real-time scoring across 5 critical dimensions (Trigger Specificity, Rule Density, Negative Guardrails, Format Compliance, Architectural Boundaries) with one-click ⚡ Auto-Fix.
- 🏷️ Trigger Tagging & Heuristic Validation: Real-time activation trigger chips with heuristic warning feedback for broad catch-all words to prevent context token bloat.
- 💻 Terminal One-Liner Stream: Native
curl,PowerShell,wget, and CLI installation endpoints (/api/raw/[formatSlug]/[presetSlug]) to install rule files directly from terminal into local project roots. - ⚡ Curated Production Presets: Statically pre-rendered presets ready for immediate use:
- Next.js 15 App Router Cursor Rules
- .NET 8 & C# 12 Minimal APIs Rules
- Spring Boot 3 & Java 21 Rules
- Django 5 & Ninja Cursor Rules
- Bun & Elysia TypeBox Rules
- Playwright E2E Browser Testing Rules
- Expo & React Native Rules
- Kubernetes & Helm Manifest Rules
- Terraform & OpenTofu IaC Rules
- Cursor Rules Pro (.mdc)
- React 19 SPA Cursor Rules
- FastAPI Python Cursor Rules
- Codebase Auditor Claude Skill
- Security Vulnerability Guard
- 🔗 Zero-Backend State Sharing: Ultra-compact permalink generation with LZ compression or canonical SEO URLs with zero server storage.
- 🗜️ Export Unified AI Kit (.zip): Download an all-in-one ZIP archive pre-structured for immediate placement into your project's repository.
Why DevScratchpad? Most online formatters and decoders secretly transmit your sensitive API keys, JWT tokens, environment secrets, and customer payloads to remote tracking servers.
DevScratchpad is 100% client-side:
- Zero API Endpoints: Every formatter, parser, hash generator, and converter executes in pure browser JavaScript & WASM.
- Zero Telemetry on Payloads: Your inputs never touch a server or database.
- Auditable & Source-Available: Inspect the network tab or the source code in this repository to verify that no network requests leave your machine.
- ⚡ Next.js 16 & Turbopack: 100% Static Site Generated (SSG) with sub-millisecond TTFB.
- 🎨 Unified Spatial Dark UI: High-contrast pitch-black canvas (
#09090B), elevated cards (#121215), and standardized monospace inputs. - 💻 Monaco Code Editor: VS Code's editor engine built-in with syntax highlighting, auto-wrap, error lines, and dual-pane diff comparison.
- ⏱️ Local Status Bars: Embedded 32px Monaco status footers displaying real-time execution speeds (ms), character volume, and syntax error lines.
- ⌨️ Command Palette: Global Ctrl + K / Cmd + K navigation to jump between tools in milliseconds.
- 🔗 Zero-Backend Sharing: Payloads are serialized directly into URL hash fragments (
#data=...), enabling private sharing with no server storage. - 💾 Local Workspace History: FIFO 15-entry local history buffer and workspace snapshot bookmarking.
| Category | Tool Name | Route | What It Does |
|---|---|---|---|
| AI & Agentic Tools | AI Skill Studio | /ai-skill-studio |
Configure, audit, and export production skills (SKILL.md, .mdc, CLAUDE.md, AGENTS.md, MCP). |
| Code Formatting | JSON Formatter | /tools/json-formatter |
Multi-indent formatting, minification, and real-time syntax error line tracking. |
| JSON Validator | /tools/json-validator |
Secure, strict JSON syntax validator to catch missing commas and string issues. | |
| XML Formatter | /tools/xml-formatter |
Format, beautify, and minify XML data structures with indentation controls. | |
| SQL Formatter | /tools/sql-formatter |
Multi-dialect query beautifier (PostgreSQL, MySQL, SQLite) with keyword casing. | |
| GraphQL Formatter | /tools/graphql-formatter |
Formats and validates GraphQL queries and schemas using the official AST parser. | |
| Security & Crypto | Base64 & Hex Inspector | /tools/base64-inspector |
Multi-encoding converter, canonical hex dump, and live Data URL image previewer. |
| JWT Decoder | /tools/jwt |
Safely decodes Header, Payload & Signature; auto-converts exp/iat timestamps. |
|
| X.509 Certificate Decoder | /tools/cert-decoder |
Decodes PEM certificates and CSRs with SANs, validity countdown, and fingerprints. | |
| SSH Key Generator | /tools/ssh-key-generator |
In-browser Ed25519/RSA/ECDSA keypair generator with OpenSSH Randomart. | |
| Password Hash & Verifier | /tools/password-hash |
Bcrypt ($2a/$2b), Argon2id, and PBKDF2 hashing and live verification matching. | |
| Hash Generator | /tools/hash |
Computes MD5, SHA-1, SHA-256, and SHA-512 in parallel client-side. | |
| HMAC Generator | /tools/hmac-generator |
Computes SHA256 & SHA512 HMAC signatures in Hex & Base64 for webhook testing. | |
| UUID Generator | /tools/uuid-generator |
Fast bulk v4 UUID generator using the native browser Crypto API. | |
| Network & Time | Cron Visualizer | /tools/cron |
Translates complex cron schedules into plain English with a 5-column breakdown grid. |
| IP / CIDR Calculator | /tools/cidr-calculator |
Calculates IPv4 network address, broadcast, wildcard mask, and usable host bounds. | |
| Code Converters | cURL to Fetch | /tools/curl-to-fetch |
Transforms cURL commands into executable JavaScript (fetch). |
| cURL to Python | /tools/curl-to-python |
Transforms cURL commands into Python (requests). |
|
| JSON to TypeScript | /tools/json-to-ts |
Generates strongly-typed TypeScript interfaces from raw JSON. | |
| JSON to Zod | /tools/json-to-zod |
Generates strict Zod schemas from raw JSON. | |
| SVG to JSX | /tools/svg-to-jsx |
Convert raw SVG code to React JSX functional components. | |
| YAML to JSON | /tools/yaml-to-json |
Convert YAML configurations into JSON payloads. | |
| Diff & Optimization | Diff Checker | /tools/diff |
Monaco side-by-side or inline code diffing with character-level additions. |
| CSS & SVG Minifier | /tools/minifier |
Strips comments and whitespace; displays byte savings and compression ratio. | |
| Regex Tester | /tools/regex |
Real-time RegExp testing with flags (g, i, m, s), match lists. |
- Node.js 18.17+ or 20+
- npm, yarn, or pnpm
# 1. Clone the repository
git clone https://github.com/Saad-web-spec/DevScratchPad.git
# 2. Enter the project directory
cd DevScratchPad
# 3. Install dependencies
npm install
# 4. Start the Turbopack development server
npm run devOpen http://localhost:3000 in your browser.
Run DevScratchpad locally on your machine for personal use and security verification:
git clone https://github.com/Saad-web-spec/DevScratchPad.git
cd DevScratchPad
npm install
npm run devContributions, feature ideas, and new utility tools are very welcome! Please check out our Contributing Guide to get started.
- Fork the Project
- Create your Feature Branch (
git checkout -b feature/AmazingNewTool) - Commit your Changes (
git commit -m 'feat: add amazing new developer tool') - Push to the Branch (
git push origin feature/AmazingNewTool) - Open a Pull Request
If DevScratchpad has saved you time or improved your workflow, consider starring ⭐ this repository and supporting its ongoing development!
DevScratchpad is distributed under the Business Source License 1.1 (BSL 1.1).
- ✅ Free for Personal, Research & Educational Use: Anyone may view, audit, run locally, and contribute to the source code.
- 🛡️ Commercial & Competitor Restrictions: Publicly hosting DevScratchpad (or any derivative) as a competing website, SaaS, API, or commercial platform is strictly prohibited without prior written commercial licensing agreement.
- See the full legal terms in
LICENSE.
Built with ❤️ by Saad • Powered by Next.js 16 & Monaco Editor