update_relation · LightRAG MCP Server MCP: Risk & Policy

WHAT IT DOES

What update_relation does on LightRAG MCP Server

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

WHY IT NEEDS A POLICY

Why update_relation needs a policy

This tool modifies existing relationships in the knowledge graph by updating their properties or attributes. This is a reversible Write operation - the changes can be undone or corrected by subsequent updates. It does not delete data (which would be Destructive), execute arbitrary code (Execute), or move financial resources (Financial).

From the tool's definition Tool description states 'Update a relationship in the knowledge graph' - the verb 'update' is explicitly a modification operation that creates or modifies data reversibly without deletion.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

update_relation Rate-limited

update_relation 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": {
    "update_relation": {
      "limits": [
        {
          "counter": "update_relation_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 LightRAG MCP Server, so you can run agents against it safely.

FAQ

Questions about update_relation

What does the update_relation tool do? +

Update a relationship in the knowledge graph. It is categorised as a Write tool in the LightRAG 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 update_relation? +

Register the LightRAG MCP Server MCP server in PolicyLayer and add a rule for update_relation: 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 LightRAG MCP Server. Nothing to install.

What risk level is update_relation? +

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

Can I rate-limit update_relation? +

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

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

update_relation is provided by the LightRAG MCP Server MCP server (lalitsuryan/lightragmcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.