What is Node9? · node9 documentation
What is Node9?
A security proxy that inspects every AI tool call before it runs.
Think of Node9 as sudo for AI agents. You define the rules once, and every agent on your machine — Claude, Gemini, Cursor, any MCP-compatible tool — operates within those boundaries automatically.
Every tool call an agent attempts — running a shell command, editing a file, hitting an API — passes through Node9 first. Node9 checks it against your policy and either allows it, flags it for human review, or blocks it. No code changes to your agent; it just works.
Execution InterceptionCore
Node9 intercepts tool calls at the MCP protocol level. It doesn't guess based on LLM output; it evaluates the actual concrete command about to be executed.
Intent-Based PolicyPolicy
Define safe zones, block dangerous verbs, or require explicit human approval for destructive commands. Configured in plain JSON.
AI Negotiation LoopSmart
When an action is blocked, Node9 doesn't just crash. It sends a structured explanation back to the AI, instructing it to pivot to a safer alternative.
Universal Agent SupportUniversal
Works with Claude Code, Gemini CLI, Cursor, and any agent that supports MCP. One proxy protects them all.
Full Audit TrailAudit
Every intercept — allowed, reviewed, or blocked — is recorded locally at
~/.node9/audit.log and optionally in Mission Control.The Simple Model
AI Agent → makes a tool call → Node9 Proxy → checks your policy → Allow / Review / Block → result returned to agent