add_pr_comments · Downscoping MCP: Risk & Policy

WHAT IT DOES

What add_pr_comments does on Downscoping

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

WHY IT NEEDS A POLICY

Why add_pr_comments needs a policy

This tool creates new data (a PR comment) and modifies the pull request by appending content. It is reversible (comments can be edited or deleted), so it is Write rather than Destructive. The severity is medium because an agent could spam comments, post misleading information to influence code review, or leak sensitive data through comments, but the blast radius is limited to a single PR's comment thread.

From the tool's definition Tool adds/creates a comment to a pull request, modifying PR state with new content.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

add_pr_comments Rate-limited

add_pr_comments 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_pr_comments": {
      "limits": [
        {
          "counter": "add_pr_comments_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 Downscoping, so you can run agents against it safely.

FAQ

Questions about add_pr_comments

What does the add_pr_comments tool do? +

Add a comment to a specific pull request. It is categorised as a Write tool in the Downscoping 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_pr_comments? +

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

What risk level is add_pr_comments? +

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

Can I rate-limit add_pr_comments? +

Yes. Add a rate_limit block to the add_pr_comments 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_pr_comments completely? +

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

add_pr_comments is provided by the Downscoping MCP server (kbroughton/downscoping-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.