graph_merge · Graph-Memory MCP: Risk & Policy

WHAT IT DOES

What graph_merge does on Graph-Memory

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

WHY IT NEEDS A POLICY

Why graph_merge needs a policy

This tool modifies the knowledge graph by merging entities, which is a Write operation (creates/modifies data reversibly). It is not Destructive because the source entity's data is moved rather than permanently deleted—it could theoretically be recovered or reversed by unmerging.

From the tool's definition Tool name is 'graph_merge' with description 'Consolidate two entities into one — moves source'. The verb 'consolidate' and action 'moves source' indicate modification of existing data by merging entities, which is reversible through graph reconstruction or…

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

graph_merge Rate-limited

graph_merge 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": {
    "graph_merge": {
      "limits": [
        {
          "counter": "graph_merge_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 Graph-Memory, so you can run agents against it safely.

FAQ

Questions about graph_merge

What does the graph_merge tool do? +

Consolidate two entities into one — moves source. It is categorised as a Write tool in the Graph-Memory MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on graph_merge? +

Register the Graph-Memory MCP server in PolicyLayer and add a rule for graph_merge: 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 Graph-Memory. Nothing to install.

What risk level is graph_merge? +

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

Can I rate-limit graph_merge? +

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

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

graph_merge is provided by the Graph-Memory MCP server (stevepridemore/graph-memory). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.