splitwise_add_friends · Splitwise MCP Server MCP

WHAT IT DOES

What splitwise_add_friends does on Splitwise MCP Server

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

WHY IT NEEDS A POLICY

Why splitwise_add_friends needs a policy

This tool creates new friend relationships in Splitwise, which is a reversible write operation. While it modifies state, it does not execute arbitrary code, delete data irreversibly, or move money. The blast radius is low since friend additions in a expense-sharing app are easily undone (friend removal or unfriending) and do not carry financial consequences by themselves.

From the tool's definition Tool name is 'splitwise_add_friends' and description states 'Add multiple friends at once.' The verb 'add' and the action of adding friends (creating new relationships in the system) indicates data modification.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

splitwise_add_friends Rate-limited

splitwise_add_friends 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": {
    "splitwise_add_friends": {
      "limits": [
        {
          "counter": "splitwise_add_friends_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 Splitwise MCP Server, so you can run agents against it safely.

FAQ

Questions about splitwise_add_friends

What does the splitwise_add_friends tool do? +

Add multiple friends at once. Provide users array with email/first_name/last_name for each. It is categorised as a Write tool in the Splitwise 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 splitwise_add_friends? +

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

What risk level is splitwise_add_friends? +

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

Can I rate-limit splitwise_add_friends? +

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

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

splitwise_add_friends is provided by the Splitwise MCP Server MCP server (svarun115/splitwise-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.