Discover all running Next.js development servers and list their available MCP tools. WHEN TO USE THIS TOOL - Use proactively in these scenarios: 1. **Before implementing ANY changes to the app**: When asked to add, modify, or fix anything in the application: - "Add a loading state" → Check c...
Bulk/mass operation — affects multiple targets
Part of the Midnight Nextjs MCP server. Enforce policies on this tool with Intercept, the open-source MCP proxy.
AI agents may call nextjs_index to permanently remove or destroy resources in Midnight Nextjs. Without a policy, an autonomous agent could delete critical data in a loop with no way to undo the damage. Intercept blocks destructive tools by default and requires explicit human approval before enabling them.
Without a policy, an AI agent could call nextjs_index in a loop, permanently destroying resources in Midnight Nextjs. There is no undo for destructive operations. Intercept blocks this tool by default and only allows it when a human explicitly approves the action.
Destructive tools permanently remove data. Block by default. Only enable with explicit approval workflows.
tools:
nextjs_index:
rules:
- action: deny
reason: "Blocked by default — enable with approval"See the full Midnight Nextjs policy for all 35 tools.
Agents calling destructive-class tools like nextjs_index have been implicated in these attack patterns. Read the full case and prevention policy for each:
Other tools in the Destructive risk category across the catalogue. The same policy patterns (deny, require_approval) apply to each.
nextjs_index is one of the critical-risk operations in Midnight Nextjs. For the full severity-focused view — only the critical-risk tools with their recommended policies — see the breakdown for this server, or browse all critical-risk tools across every MCP server.
Discover all running Next.js development servers and list their available MCP tools. WHEN TO USE THIS TOOL - Use proactively in these scenarios: 1. **Before implementing ANY changes to the app**: When asked to add, modify, or fix anything in the application: - "Add a loading state" → Check current component structure and routes first - "Fix the navigation" → Inspect existing routes and components - "Update the API endpoint" → Query current routes and data flows - "Add error handling" → Check runtime errors and component hierarchy - "Refactor the auth logic" → Inspect current auth implementation and routes - "Optimize performance" → Check runtime diagnostics and component tree Use this to understand where changes should be made and what currently exists. 2. **For diagnostic and investigation questions**: - "What's happening?" / "What's going on?" / "Why isn't this working?" - "Check the errors" / "See what's wrong" - "What routes are available?" / "Show me the routes" - "Clear the cache" / "Reset everything" - Questions about build status, compilation errors, or runtime diagnostics 3. **For agentic codebase search**: Use this as FIRST CHOICE for searching the currently running app. If not found, fallback to static codebase search tools. KEY PRINCIPLE: If the request involves the running Next.js application (whether to investigate OR modify it), query the runtime FIRST to understand current state before proceeding. REQUIREMENTS: - Next.js 16 or later (MCP support was added in v16) - If you're on Next.js 15 or earlier, use the 'upgrade-nextjs-16' MCP prompt to upgrade first Next.js 16+ exposes an MCP (Model Context Protocol) endpoint at /_next/mcp automatically when the dev server starts. No configuration needed - MCP is enabled by default in Next.js 16 and later. This tool discovers all running Next.js servers and returns: - Server port, PID, and URL - Complete list of available MCP tools for each server - Tool descriptions and input schemas After calling this tool, use 'nextjs_call' to execute specific tools. [IMPORTANT] If auto-discovery returns no servers: 1. Ask the user which port their Next.js dev server is running on 2. Call this tool again with the 'port' parameter set to the user-provided port If the MCP endpoint is not available: 1. Ensure you're running Next.js 16 or later (use the 'upgrade-nextjs-16' prompt to upgrade) 2. Verify the dev server is running (npm run dev) 3. Check that the dev server started successfully without errors. It is categorised as a Destructive tool in the Midnight Nextjs MCP Server, which means it can permanently delete or destroy data. Block by default and require explicit approval.
Add a rule in your Intercept YAML policy under the tools section for nextjs_index. You can allow, deny, rate-limit, or validate arguments. Then run Intercept as a proxy in front of the Midnight Nextjs MCP server.
nextjs_index is a Destructive tool with critical risk. Critical-risk tools should be blocked by default and only enabled with explicit human approval.
Yes. Add a rate_limit block to the nextjs_index rule in your Intercept policy. For example, setting max: 10 and window: 60 limits the tool to 10 calls per minute. Rate limits are tracked per agent session and reset automatically.
Set action: deny in the Intercept policy for nextjs_index. The AI agent will receive a policy violation error and cannot call the tool. You can also include a reason field to explain why the tool is blocked.
nextjs_index is provided by the Midnight Nextjs MCP server (midnight-nextjs-mcp). Intercept sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Deterministic policy on every MCP tool call. Per-identity grants. Full audit log.