linear_add_comment · Linear MCP Server MCP: Risk & Policy

WHAT IT DOES

What linear_add_comment does on Linear MCP Server

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

WHY IT NEEDS A POLICY

Why linear_add_comment needs a policy

This tool creates new comment data within Linear issues, which is a reversible modification. It does not execute arbitrary code, delete data irreversibly, or move money. The medium severity reflects that while comments can spread misinformation or spam if misused by an LLM agent, the impact is limited in scope (comments can be edited/deleted) and contained to a single issue tracking system.

From the tool's definition Tool description states it 'Adds a comment to an existing Linear issue' and 'Returns the created comment', indicating creation of new data (comments) within an issue tracking system.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

linear_add_comment Rate-limited

linear_add_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": {
    "linear_add_comment": {
      "limits": [
        {
          "counter": "linear_add_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 Linear MCP Server, so you can run agents against it safely.

FAQ

Questions about linear_add_comment

What does the linear_add_comment tool do? +

Adds a comment to an existing Linear issue. Supports markdown formatting in the comment body. Can optionally specify a custom user name and avatar for the comment. Returns the created comment. It is categorised as a Write tool in the Linear MCP Server MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on linear_add_comment? +

Register the Linear MCP Server MCP server in PolicyLayer and add a rule for linear_add_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 Linear MCP Server. Nothing to install.

What risk level is linear_add_comment? +

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

Can I rate-limit linear_add_comment? +

Yes. Add a rate_limit block to the linear_add_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 linear_add_comment completely? +

Set action: deny in the PolicyLayer policy for linear_add_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 linear_add_comment? +

linear_add_comment is provided by the Linear MCP Server MCP server (veddnd/l-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.