SmuggleCheck
Click on "Deploy Server".
Wait a few minutes for the server to deploy. Once ready, it will show a "Started" state.
In the chat, type
@followed by the MCP server name and your instructions, e.g., "@SmuggleCheckscan this message for hidden prompt-injection characters"
That's it! The server will respond to your query, and you can continue using it as needed.
Here is a step-by-step guide with screenshots.
SmuggleCheck
Find hidden prompt-injection text: ASCII smuggling, zero-width/emoji stego, bidi, homoglyphs. One layer, not a full defense: it does not judge prompt injection written in plain, visible words.
SmuggleCheck is not affiliated with, endorsed or sponsored by Meta, OpenAI, Anthropic, Google, Mistral AI, DeepSeek, Alibaba (Qwen), the Unicode Consortium or any other AI vendor, model vendor or MCP client maker.
Live service
Web app and API: https://smugglecheck.mike-tusa.workers.dev/
Plans: Free, no paid plan (https://smugglecheck.mike-tusa.workers.dev/)
Support: digitalpromohub.support@gmail.com
Related MCP server: PromptWall MCP Server
Use it from an AI assistant (MCP)
SmuggleCheck is a remote MCP server (Streamable HTTP) at https://smugglecheck.mike-tusa.workers.dev/mcp. Tools: scan_text, compare_strings.
Cursor, Cline and Windsurf accept this config:
{
"mcpServers": {
"smugglecheck": {
"type": "http",
"url": "https://smugglecheck.mike-tusa.workers.dev/mcp"
}
}
}Claude Desktop: open Settings > Connectors, choose "Add custom connector" and paste https://smugglecheck.mike-tusa.workers.dev/mcp. Or, for clients that only support local (stdio) servers, use the mcp-remote bridge: npx mcp-remote https://smugglecheck.mike-tusa.workers.dev/mcp.
VS Code uses a servers key instead of mcpServers.
The server.json file is the MCP Registry manifest for this server.
Run your own copy
Requires Node.js 22+ and a Cloudflare account.
npm install
npx wrangler@4 dev # local dev serverwrangler.toml is a template: create your own KV namespaces / D1 databases / rate-limit namespaces and replace the <PLACEHOLDER> values before npx wrangler@4 deploy. Any secrets the Worker reads go in wrangler secret put (or .dev.vars locally), never in the repo.
Optional Worker secrets (leave unset if you do not need them): GLAMA_CLAIM (your glama.ai connector claim token, served at /.well-known/glama.json); VISITOR_SALT (a random salt for the privacy-friendly daily unique-visitor counter; while it is unset, no visitors are counted); MCP_REGISTRY_AUTH (your MCP Registry HTTP-domain proof, v=MCPv1; k=ed25519; p=<public key>, served at /.well-known/mcp-registry-auth; 404 while unset).
Third-party data
The code in this repository is licensed under MIT. The homoglyph data file src/lib/confusables-data.js is NOT MIT: it is generated from Unicode confusables.txt (UTS #39 18.0.0), © Unicode, Inc., and is licensed under the Unicode License v3 (https://www.unicode.org/license.txt). See NOTICE.
License
Code: MIT (c) Digital Promo Hub, see LICENSE. Homoglyph data file src/lib/confusables-data.js: Unicode License v3, © Unicode, Inc., see NOTICE.
This server cannot be deployed
Maintenance
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