apply_template · Tages MCP: Risk & Policy

WHAT IT DOES

What apply_template does on Tages

AI agents use apply_template to create or update resources in Tages — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Tages environment.

WHY IT NEEDS A POLICY

Why apply_template needs a policy

The tool writes new memory records to persistent storage (SQLite) in a predictable, structured way via template population. This is a Write operation because it creates new data with side effects, but severity is low: the blast radius of a misused memory creation is confined to that single memory artifact, causing no financial harm, code execution, or data destruction.

From the tool's definition Tool performs 'Create a memory from a filled template with automatic key generation' — the word 'Create' indicates data creation; the mechanism is reversible (memory can be updated or deleted), not destructive.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

apply_template Rate-limited

apply_template 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.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "apply_template": {
      "limits": [
        {
          "counter": "apply_template_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

LIMIT THIS TOOL →

Instant setup, no code required.

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

FAQ

Questions about apply_template

What does the apply_template tool do? +

Create a memory from a filled template with automatic key generation. It is categorised as a Write tool in the Tages MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on apply_template? +

Register the Tages MCP server in PolicyLayer and add a rule for apply_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 Tages. Nothing to install.

What risk level is apply_template? +

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

Can I rate-limit apply_template? +

Yes. Add a rate_limit block to the apply_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 apply_template completely? +

Set action: deny in the PolicyLayer policy for apply_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 apply_template? +

apply_template is provided by the Tages MCP server (ryantlee25-droid/tages). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.