execution_retry · N8n Fabric MCP: Risk & Policy

WHAT IT DOES

What execution_retry does on N8n Fabric

AI agents invoke execution_retry to trigger actions in N8n Fabric. What it does depends on the arguments the agent supplies, and its effects often reach beyond the immediate call — builds kicked off, notifications sent, workflows started.

WHY IT NEEDS A POLICY

Why execution_retry needs a policy

Retrying a failed execution re-runs an automated workflow, which constitutes executing an external operation. The blast radius is medium because it triggers whatever actions the workflow was designed to perform, which could include writes, API calls, or other side effects depending on the workflow content.

From the tool's definition 'Retry a failed execution' - re-triggers an existing workflow execution

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

execution_retry Rate-limited

execution_retry stays usable, but rate-capped — a runaway agent can't fire it dozens of times a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "execution_retry": {
      "limits": [
        {
          "counter": "execution_retry_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}

RATE-LIMIT THIS TOOL →

Instant setup, no code required.

PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches N8n Fabric, so you can run agents against it safely.

FAQ

Questions about execution_retry

What does the execution_retry tool do? +

Retry a failed execution. It is categorised as a Execute tool in the N8n Fabric MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on execution_retry? +

Register the N8n Fabric MCP server in PolicyLayer and add a rule for execution_retry: 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 Fabric. Nothing to install.

What risk level is execution_retry? +

execution_retry is a Execute tool with high risk. Execute tools should be rate-limited and have argument validation enabled.

Can I rate-limit execution_retry? +

Yes. Add a rate_limit block to the execution_retry 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 execution_retry completely? +

Set action: deny in the PolicyLayer policy for execution_retry. 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 execution_retry? +

execution_retry is provided by the N8n Fabric MCP server (ry-ops/n8n-fabric). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.