Medium Risk

connect_nodes

Connect two nodes in a workflow

How to control connect_nodes ↓

What connect_nodes does on n8n Workflow Builder MCP Server

AI agents use connect_nodes to create or update resources in n8n Workflow Builder MCP Server — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your n8n Workflow Builder MCP Server environment.

Medium Risk

Why connect_nodes needs a policy

This tool creates or modifies workflow topology by connecting nodes, which is a reversible change to workflow data. It does not execute workflows, delete data, or move money. While it could theoretically be misconfigured to create problematic workflows, the immediate action is data modification (Write category).

From the tool's definition The tool 'connect_nodes' modifies workflow structure by establishing connections between nodes, which is a reversible creation/modification of workflow data. The description states it 'Connect[s] two nodes in a workflow,' indicating structural modification.

Documented attack patterns abuse exactly the kind of access connect_nodes gives an agent:

How to control connect_nodes

PolicyLayer is an MCP gateway — it sits between your AI agents and n8n Workflow Builder MCP Server, and nothing reaches the server without passing your rules. This is the rule we recommend for connect_nodes:

policy.json
{
  "version": "1",
  "default": "deny",
  "tools": {
    "connect_nodes": {
      "limits": [
        {
          "counter": "connect_nodes_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

connect_nodes stays usable, but capped — an agent stuck in a loop can't make hundreds of changes a minute. Everything else on the server is denied unless you say otherwise.

  1. Create a free account and register n8n Workflow Builder MCP Server — nothing to install.
  2. Add this policy — paste it, or build it visually.
  3. Point your MCP client (Claude, Cursor, anything) at your gateway URL.
LIMIT THIS TOOL →

Free to start. No card required.

Related tools and policies

Go deeper

Questions about connect_nodes

What does the connect_nodes tool do? +

Connect two nodes in a workflow. It is categorised as a Write tool in the n8n Workflow Builder MCP Server MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on connect_nodes? +

Register the n8n Workflow Builder MCP Server MCP server in PolicyLayer and add a rule for connect_nodes: allow, deny, rate-limit, or require approval. Point your MCP client at the PolicyLayer proxy URL and the rule is enforced on every call, before it reaches n8n Workflow Builder MCP Server. Nothing to install.

What risk level is connect_nodes? +

connect_nodes is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.

Can I rate-limit connect_nodes? +

Yes. Add a rate_limit block to the connect_nodes rule in your PolicyLayer 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.

How do I block connect_nodes completely? +

Set action: deny in the PolicyLayer policy for connect_nodes. 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.

What MCP server provides connect_nodes? +

connect_nodes is provided by the n8n Workflow Builder MCP Server MCP server (makafeli/n8n-workflow-builder). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

Enforce policy on every n8n Workflow Builder MCP Server tool call.

Start from n8n Workflow Builder MCP Server, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.

Free to start. No card required.

34 n8n Workflow Builder MCP Server tools catalogued and risk-classified — across an index of 43,000+ MCP servers.

// GET IN TOUCH

Have a question or want to learn more? Send us a message.

Message sent.

We'll get back to you soon.