option_market_data

THE RISK

Low Risk

Why option_market_data needs a policy

This tool retrieves market data (quotes, prices, Greeks, etc.) for options contracts. It is a read-only query operation that returns information without side effects, modifying positions, or executing financial transactions. No money moves and no data is altered. This is a standard market data lookup operation common to financial APIs.

From the tool's definition Tool name is 'option_market_data' and description states 'Gets market data for a specific option contract.' The verb 'Gets' indicates retrieval of data with no modification or execution of trades.

Documented attack patterns abuse exactly the kind of access option_market_data gives an agent:

POLICY

How to control option_market_data

PolicyLayer is an MCP gateway — it sits between your AI agents and Open Stocks MCP, and nothing reaches the server without passing your rules. This is the rule we recommend for option_market_data:

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "option_market_data": {}
  }
}

option_market_data is read-only, so it stays allowed — but everything else on the server is denied unless you say otherwise.

Create a free account and register Open Stocks MCP — nothing to install.
Add this policy — paste it, or build it visually.
Point your MCP client (Claude, Cursor, anything) at your gateway URL.

CAP THIS TOOL →

Free to start. No card required.

EXPLORE

Related tools and policies

More Open Stocks MCP tools

Financial schwab_order_sell_stop Place a stop sell order for stock. Financial sell_stock_stop_loss Places a stop loss sell order for a stock. Financial buy_option_limit Places a limit buy order for an option. Financial buy_stock_limit Places a limit buy order for a stock. Financial buy_stock_market Places a market buy order for a stock. Financial option_credit_spread option_credit_spread Financial option_debit_spread option_debit_spread Financial schwab_buy_stock_limit Place a limit buy order for stock.

All 152 Open Stocks MCP tools →

Read tools on other servers

M-Team MCP Server get_torrent_detail YouTube MCP Server search_channel Android Forensics ADB MCP Server parse_browser_history 0xarchive web3_challenge

Go deeper

The MCP Attack Database → Documented attack patterns against MCP deployments — and the policies that stop them.
Data exfiltration → How read access becomes an exfiltration channel when chained with untrusted content.
MCP token cost → What connecting this server costs in context-window tokens on every request.
Rate Limiting MCP Tool Calls: A Practical Guide →
MCP Security: Why Prompt Guardrails Aren't Enough →

FAQ

Questions about option_market_data

What does the option_market_data tool do? +

Gets market data for a specific option contract. It is categorised as a Read tool in the Open Stocks MCP MCP Server, which means it retrieves data without modifying state.

How do I enforce a policy on option_market_data? +

Register the Open Stocks MCP server in PolicyLayer and add a rule for option_market_data: 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 Open Stocks MCP. Nothing to install.

What risk level is option_market_data? +

option_market_data is a Read tool with low risk. Read-only tools are generally safe to allow by default.

Can I rate-limit option_market_data? +

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

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

option_market_data is provided by the Open Stocks MCP server (open-agent-tools/open-stocks-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

Enforce policy on every Open Stocks MCP tool call.

Start from Open Stocks MCP, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.

CHECK YOUR STACK →