add_captions · Media-Editor- MCP: Risk & Policy

WHAT IT DOES

What add_captions does on Media-Editor-MCP

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

WHY IT NEEDS A POLICY

Why add_captions needs a policy

This tool creates or modifies captions in a video project, which is a reversible write operation. The description is empty, reducing confidence slightly. Severity is medium because caption changes could alter project output significantly, but are easily undone and carry no financial or destructive impact. The tool operates within an editing context where modifications are expected and reversible.

From the tool's definition Tool named 'add_captions' on a media editing server (CapCut/Adobe Premiere Pro control). The 'add_' prefix and context of sibling tools (add_animation, add_audio, add_text, add_filter, etc.) indicate creation/modification of media elements.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

add_captions Rate-limited

add_captions 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": {
    "add_captions": {
      "limits": [
        {
          "counter": "add_captions_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 Media-Editor-MCP, so you can run agents against it safely.

FAQ

Questions about add_captions

What does the add_captions tool do? +

add_captions. It is categorised as a Write tool in the Media-Editor-MCP MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on add_captions? +

Register the Media-Editor- MCP server in PolicyLayer and add a rule for add_captions: 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 Media-Editor-MCP. Nothing to install.

What risk level is add_captions? +

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

Can I rate-limit add_captions? +

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

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

add_captions is provided by the Media-Editor- MCP server (nguyenph88/media-editor-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.