Returns a mapping of all exchanges to unique CoinMarketCap IDs.
AI agents call exchangeMap to retrieve information from CoinMarketCap MCP without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
This tool retrieves and queries static reference data (exchange-to-ID mappings) without any side effects. It is a standard lookup/fetch operation typical of Read category tools. The blast radius of misuse is minimal since it only exposes public exchange metadata. Confidence is high given the clear, unambiguous read-only nature of the operation.
From the tool's definition Tool description states it 'Returns a mapping of all exchanges to unique CoinMarketCap IDs' — a pure data retrieval operation with no modification, deletion, or execution capabilities.
Documented attack patterns abuse exactly the kind of access exchangeMap gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and CoinMarketCap MCP, and nothing reaches the server without passing your rules. This is the rule we recommend for exchangeMap:
{
"version": "1",
"default": "deny",
"tools": {
"exchangeMap": {}
}
}exchangeMap is read-only, so it stays allowed — but everything else on the server is denied unless you say otherwise.
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Returns a mapping of all exchanges to unique CoinMarketCap IDs. It is categorised as a Read tool in the CoinMarketCap MCP MCP Server, which means it retrieves data without modifying state.
Register the CoinMarketCap MCP server in PolicyLayer and add a rule for exchangeMap: 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 CoinMarketCap MCP. Nothing to install.
exchangeMap 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 exchangeMap 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 exchangeMap. 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.
exchangeMap is provided by the CoinMarketCap MCP server (shinzo-labs/coinmarketcap-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Deterministic rules across all 51 CoinMarketCap MCP tools. Per-identity grants. Full audit log. Live in minutes. Nothing to install.
Free to start. No card required.
51 CoinMarketCap MCP tools catalogued and risk-classified — across an index of 42,500+ MCP servers.