follow_user · Lichess Integration MCP: Risk & Policy

WHAT IT DOES

What follow_user does on Lichess Integration

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

PARAMETERS

Parameter	Type	Required	Description
`username`	string	—	Username of the player to follow

Parameters from the server's own tool schema.

WHY IT NEEDS A POLICY

Why follow_user needs a policy

Following a user creates a social relationship on the platform. This is a reversible write action (you can unfollow), with minimal blast radius as it only affects the follower's social graph.

From the tool's definition Follow a player

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

follow_user Rate-limited

follow_user 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": {
    "follow_user": {
      "limits": [
        {
          "counter": "follow_user_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 Lichess Integration, so you can run agents against it safely.

FAQ

Questions about follow_user

What does the follow_user tool do? +

Follow a player. It is categorised as a Write tool in the Lichess Integration MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

What parameters does follow_user accept? +

follow_user accepts 1 parameter: username. The full parameter table on this page comes from the server's own tool schema.

How do I enforce a policy on follow_user? +

Register the Lichess Integration MCP server in PolicyLayer and add a rule for follow_user: 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 Lichess Integration. Nothing to install.

What risk level is follow_user? +

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

Can I rate-limit follow_user? +

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

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

follow_user is provided by the Lichess Integration MCP server (karayaman/lichess-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.