get_option_chain
AI agents call get_option_chain to retrieve information from Yahoo Finance MCP Server without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
get_option_chain retrieves options pricing and contract information—a read-only query with no side effects. There is no capability to execute trades, modify data, or trigger financial transactions. The blast radius of misuse is minimal; worst case, an agent retrieves unwanted financial data, which poses no financial or destructive risk.
From the tool's definition Tool name 'get_option_chain' indicates a retrieval operation (get prefix), and the server's overall purpose is to 'retrieve stock market data and financial information' from Yahoo Finance.
Attacks that exploit this kind of access
get_option_chain. It is categorised as a Read tool in the Yahoo Finance MCP Server MCP Server, which means it retrieves data without modifying state.
Register the Yahoo Finance MCP Server MCP server in PolicyLayer and add a rule for get_option_chain: 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 Yahoo Finance MCP Server. Nothing to install.
get_option_chain is a Read tool with low risk. Read-only tools are generally safe to allow by default.
Yes. Add a rate_limit block to the get_option_chain 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 get_option_chain. 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.
get_option_chain is provided by the Yahoo Finance MCP Server MCP server (peidaqi/yfinance-mcp-server). 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 →