Create a listen key for Portfolio Margin user data stream. The listen key is used to subscribe to account updates via WebSocket.
AI agents use BinancePortfolioMarginCreateListenKey to create or update resources in BNB Chain MCP — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your BNB Chain MCP environment.
This tool creates a listen key (a session token) for WebSocket subscriptions. It writes/creates a new resource (the listen key) on Binance's servers but does not move funds, execute trades, delete data, or run code. The blast radius is low since a listen key only grants read-only stream access to account updates, though it does expose account activity data if misused.
From the tool's definition Create a listen key for Portfolio Margin user data stream
Documented attack patterns abuse exactly the kind of access BinancePortfolioMarginCreateListenKey gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and BNB Chain MCP, and nothing reaches the server without passing your rules. This is the rule we recommend for BinancePortfolioMarginCreateListenKey:
{
"version": "1",
"default": "deny",
"tools": {
"BinancePortfolioMarginCreateListenKey": {
"limits": [
{
"counter": "binanceportfoliomargincreatelistenkey_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
}BinancePortfolioMarginCreateListenKey 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.
Free to start. No card required.
Create a listen key for Portfolio Margin user data stream. The listen key is used to subscribe to account updates via WebSocket. It is categorised as a Write tool in the BNB Chain MCP MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the BNB Chain MCP server in PolicyLayer and add a rule for BinancePortfolioMarginCreateListenKey: 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 BNB Chain MCP. Nothing to install.
BinancePortfolioMarginCreateListenKey is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.
Yes. Add a rate_limit block to the BinancePortfolioMarginCreateListenKey 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 BinancePortfolioMarginCreateListenKey. 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.
BinancePortfolioMarginCreateListenKey is provided by the BNB Chain MCP server (nirholas/bnbchain-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Deterministic rules across all 1240 BNB Chain MCP tools. Per-identity grants. Full audit log. Live in minutes. Nothing to install.
Free to start. No card required.
1240 BNB Chain MCP tools catalogued and risk-classified — across an index of 42,500+ MCP servers.