@aegis-sdk/next

@aegis-sdk/next

Next.js integration for scanning LLM chat messages against prompt injection attacks.

Part of the Aegis.js prompt injection defense toolkit.

Installation

npm install @aegis-sdk/next @aegis-sdk/core

Quick Start

// app/api/chat/route.ts
import { Aegis } from '@aegis-sdk/core';
import { withAegis } from '@aegis-sdk/next';
import { streamText } from 'ai';
import { openai } from '@ai-sdk/openai';

const aegis = new Aegis({ policy: 'strict' });

export const POST = withAegis(aegis, async (req, safeMessages) => {
  const result = streamText({
    model: openai('gpt-4o'),
    messages: safeMessages,
  });
  return result.toDataStreamResponse();
});

API

withAegis(aegisOrConfig, handler, options?)

Higher-order function that wraps a Next.js App Router route handler. Parses the request body, scans messages through aegis.guardInput(), and passes safe messages to your handler. Returns 403 with violation details if input is blocked.

Option	Type	Default	Description
messagesProperty	string	"messages"	Property on the request body to read messages from
scanStrategy	ScanStrategy	"last-user"	Which messages to scan
onBlocked	(req, error) => Response	--	Custom error handler. Return a Response to take over

Your handler receives (req, safeMessages, { instance, auditLog }).

aegisMiddleware(options?)

Creates a Next.js Edge Middleware function for request-level scanning. Designed for use in middleware.ts at the project root.

// middleware.ts
import { aegisMiddleware } from '@aegis-sdk/next';

const aegisMw = aegisMiddleware({
  aegis: { policy: 'strict' },
  matchRoutes: ['/api/chat', '/api/ai'],
});

export async function middleware(req: Request) {
  return aegisMw(req);
}

export const config = {
  matcher: ['/api/chat/:path*', '/api/ai/:path*'],
};

Option	Type	Default	Description
aegis	AegisConfig | Aegis	{}	Aegis configuration or pre-constructed instance
matchRoutes	(string | RegExp)[]	--	Route patterns to scan. If omitted, all POST requests are scanned
messagesProperty	string	"messages"	Property on the request body to read messages from
scanStrategy	ScanStrategy	"last-user"	Which messages to scan
onBlocked	(req, error) => Response	--	Custom error handler

guardMessages(aegis, messages, options?)

Scans messages directly without using withAegis or Edge Middleware. Useful in Server Actions, custom API routes, or WebSocket handlers. Throws AegisInputBlocked if input is blocked.

Re-exports

Aegis, AegisInputBlocked, AegisSessionQuarantined, AegisSessionTerminated, and all core types are re-exported for convenience.

Learn More

• Documentation
• GitHub

License

MIT