LLM Sandbox vs Next Devtools MCP

A side-by-side look at the LLM Sandbox and Next Devtools MCP MCP servers: transport, auth, tools, quality signals, and the config to install either one in Claude, Cursor, Windsurf or VS Code.

LLM Sandbox logoLLM SandboxCode Execution · Local subprocess (stdio)Securely run LLM-generated code in isolated containers across 7 languages and 4 backends.60GoodAuth: not declaredNext Devtools MCP logoNext Devtools MCPDeveloper Tools · Local subprocess (stdio)Official Next.js MCP server for coding agents. Provides runtime diagnostics, route inspection, dev server logs, docs search, and upgrade guides. Requires Next.js 16+ dev server for full runtime features.86ExcellentAuth: no auth required

Verdict: choose LLM Sandbox for code execution work as a local process; choose Next Devtools MCP for developer tools as a local process. You can also run both side by side in one mcpServers block.

Which MCP server should you choose?

LLM Sandbox logoChoose LLM Sandbox when

  • You need dedicated capabilities in the Code Execution domain.
  • You prefer a local stdio subprocess transport.
  • You want tools like execute_code, get_supported_languages, get_language_details.
Explore LLM Sandbox

Next Devtools MCP logoChoose Next Devtools MCP when

  • You need dedicated capabilities in the Developer Tools domain.
  • You prefer a local stdio subprocess transport.
  • Its auth model fits you: No auth required.
  • You want tools like nextjs_index, nextjs_call, nextjs_docs.
Explore Next Devtools MCP

Feature & specification comparison

Rows where the two servers differ are marked.

SpecLLM Sandbox logoLLM SandboxNext Devtools MCP logoNext Devtools MCP
CategoryCode ExecutionDeveloper Tools
Quality signal60/100 · Good86/100 · Excellent
Install commandConfirmedConfirmed
TransportLocal subprocess (stdio)Local subprocess (stdio)
AuthNot declaredNo auth required
PricingNot declaredFree
Required env varsNone listedNone listed
Verified ownerCommunity listing Verified
GitHub stars1,136832
Directory activity 4 views 0 installs 0 upvotes 9 views 0 installs 1 upvotes
Tools34

Tools & capabilities

LLM Sandbox tools 3

  • execute_code
  • get_supported_languages
  • get_language_details

Next Devtools MCP tools 4

  • nextjs_indexDiscover running Next.js dev servers and list each one's runtime MCP tools.
  • nextjs_callCall a runtime tool on a discovered server (errors, routes, logs, Server Actions).
  • nextjs_docsGateway.** Point the agent at version-accurate docs in `node_modules/next/dist/docs/`.
  • browser_evalGateway.** Point the agent at the [`agent-browser`](https://github.com/vercel-labs/agent-browser) CLI for browser automation.

Ready-to-paste client configs

Paste either block (or both) into your client config, e.g. claude_desktop_config.json or ~/.cursor/mcp.json. We only show a config when the install command is confirmed.

LLM Sandbox

mcpServers (Claude Desktop / Cursor)
{
  "mcpServers": {
    "llm-sandbox": {
      "command": "uvx",
      "args": [
        "llm-sandbox"
      ]
    }
  }
}

Next Devtools MCP

mcpServers (Claude Desktop / Cursor)
{
  "mcpServers": {
    "vercel-next-devtools-mcp": {
      "command": "npx",
      "args": [
        "-y",
        "next-devtools-mcp@latest"
      ]
    }
  }
}

Frequently asked questions

LLM Sandbox is categorized under Code Execution and uses a local stdio subprocess. Next Devtools MCP belongs to Developer Tools and uses a local stdio subprocess. Pick LLM Sandbox for code execution work and Next Devtools MCP for developer tools.

Copy the mcpServers block from the config section on this page into your client's config (for example claude_desktop_config.json or ~/.cursor/mcp.json), then fully restart the client.

LLM Sandbox has no declared pricing — check the project's own site. Next Devtools MCP is listed as free. Auth: no auth required. If a server needs environment variables such as API keys, define them under the env key in your client's MCP config.

Yes. MCP clients support multiple servers: add llm-sandbox and vercel-next-devtools-mcp as separate keys in the same mcpServers object, and your assistant will call tools from either one.

On AllMCPs, LLM Sandbox has a quality signal of 60/100 (Good) with 4 views, 0 installs and 1,136 GitHub stars. Next Devtools MCP has 86/100 (Excellent) with 9 views, 0 installs and 832 GitHub stars.