Calculate optimal bet size using Kelly Criterion
AI agents use calculate_kelly_bet_size to commit financial operations through Fantasy MCP — usually the final step of a payment, billing, or trading workflow. A call moves real money.
The Kelly Criterion is a formula used to determine the optimal size of a series of bets to maximize long-term wealth growth. This tool directly outputs how much money a user should wager, making it a financial tool. While it doesn't execute a transaction itself, it is the proximate step before placing a bet and directly drives financial decisions.
From the tool's definition Calculate optimal bet size using Kelly Criterion — directly computes financial betting stake sizes, which constitutes committing financial obligations in a gambling context
Attacks that exploit this kind of access
Calculate optimal bet size using Kelly Criterion. It is categorised as a Financial tool in the Fantasy MCP MCP Server, which means it involves financial transactions. Block by default and require explicit approval.
Register the Fantasy MCP server in PolicyLayer and add a rule for calculate_kelly_bet_size: 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 Fantasy MCP. Nothing to install.
calculate_kelly_bet_size is a Financial tool with critical risk. Critical-risk tools should be blocked by default and only enabled with explicit human approval.
Yes. Add a rate_limit block to the calculate_kelly_bet_size 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.
Set action: deny in the PolicyLayer policy for calculate_kelly_bet_size. 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.
calculate_kelly_bet_size is provided by the Fantasy MCP server (mattarm/fantasy_mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Every MCP server has a record like this.
Type a name, get the same breakdown: verified identity, auth posture, risk grade, capabilities, recommended policy.
Teams ship this data inside their own products. See what a licence covers →