create_comment · MCP Linear App MCP: Risk & Policy

WHAT IT DOES

What create_comment does on MCP Linear App

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

WHY IT NEEDS A POLICY

Why create_comment needs a policy

Creating a comment adds data to an issue but does not delete, destroy, or execute arbitrary code. It is a reversible Write operation with low blast radius since comments can be removed. No financial impact or data destruction occurs.

From the tool's definition Tool name is 'create_comment' and description states it 'creates a comment on an issue in Linear'. This is a creation operation that modifies data (adds a comment) but is reversible (comments can be deleted or edited).

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

create_comment Rate-limited

create_comment 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": {
    "create_comment": {
      "limits": [
        {
          "counter": "create_comment_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 MCP Linear App, so you can run agents against it safely.

FAQ

Questions about create_comment

What does the create_comment tool do? +

A tool that creates a comment on an issue in Linear. It is categorised as a Write tool in the MCP Linear App MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on create_comment? +

Register the MCP Linear App MCP server in PolicyLayer and add a rule for create_comment: 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 MCP Linear App. Nothing to install.

What risk level is create_comment? +

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

Can I rate-limit create_comment? +

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

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

create_comment is provided by the MCP Linear App MCP server (zalab-inc/mcp-linear-app). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.