trigger_flow · Directus MCP Server MCP: Risk & Policy

WHAT IT DOES

What trigger_flow does on Directus MCP Server

AI agents invoke trigger_flow to trigger actions in Directus MCP Server. 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 trigger_flow needs a policy

This tool triggers external workflow execution (a 'flow' in Directus). Flows can perform arbitrary operations including data modifications, API calls, notifications, and integrations. While the tool itself doesn't directly execute code like an exec() function, it triggers execution of automation logic configured elsewhere in the system.

From the tool's definition Tool name is 'trigger_flow' and description states it 'Trigger a flow with GET or POST webhook trigger'. Flows in workflow automation systems execute business logic, scripts, or external operations when triggered.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

trigger_flow Rate-limited

trigger_flow 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": {
    "trigger_flow": {
      "limits": [
        {
          "counter": "trigger_flow_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 Directus MCP Server, so you can run agents against it safely.

FAQ

Questions about trigger_flow

What does the trigger_flow tool do? +

Trigger a flow with GET or POST webhook trigger. For GET: {id:. It is categorised as a Execute tool in the Directus MCP Server MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on trigger_flow? +

Register the Directus MCP Server MCP server in PolicyLayer and add a rule for trigger_flow: 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 Directus MCP Server. Nothing to install.

What risk level is trigger_flow? +

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

Can I rate-limit trigger_flow? +

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

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

trigger_flow is provided by the Directus MCP Server MCP server (skeyelab/directus-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.