render_message_template

Server Huly @firfi/huly-mcp

Category Execute

Risk class High

Parameters 00 required

WHAT IT DOES

What render_message_template does on Huly

AI agents invoke render_message_template to trigger actions in Huly. 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 render_message_template needs a policy

render_message_template triggers real processes with real consequences. An agent gone sideways doesn't fire it once — it starts dozens of builds, sends mass notifications, or burns through compute before anyone looks up.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

render_message_template Rate-limited

render_message_template 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": {
    "render_message_template": {
      "limits": [
        {
          "counter": "render_message_template_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 Huly, so you can run agents against it safely.

FAQ

Questions about render_message_template

What does the render_message_template tool do? +

Render one global Huly message template by template ID or exact title. Substitutes only caller-provided values for matching dollar-brace placeholder field IDs from placeholderFieldIds; does not execute Huly TemplateField provider resources. Unresolved placeholders remain in renderedMessage and are reported in unresolvedFieldIds. It is categorised as a Execute tool in the Huly MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on render_message_template? +

Register the Huly MCP server in PolicyLayer and add a rule for render_message_template: 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 Huly. Nothing to install.

What risk level is render_message_template? +

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

Can I rate-limit render_message_template? +

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

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

render_message_template is provided by the Huly MCP server (@firfi/huly-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.