Current Bitcoin network fee rates and mempool backlog from mempool.space. Returns recommended fee rates (sat/vByte) for fastest/half-hour/hour/economy/minimum confirmation, plus mempool size (tx count, vsize, total fees waiting). Keyless, live. The BTC counterpart to crypto.gas-oracle.
AI agents call crypto.btc-fees to retrieve information from Mcp without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
This tool queries and retrieves publicly available Bitcoin network fee information and mempool statistics. It has no side effects, cannot modify state, execute transactions, or commit financial obligations. The read-only nature and lack of write/execute/financial action capabilities place it firmly in the Read category with low severity.
From the tool's definition Tool description states it 'Returns recommended fee rates...plus mempool size' — purely retrieval of current network data with no capability to modify, delete, or execute transactions.
Attacks that exploit this kind of access
Current Bitcoin network fee rates and mempool backlog from mempool.space. Returns recommended fee rates (sat/vByte) for fastest/half-hour/hour/economy/minimum confirmation, plus mempool size (tx count, vsize, total fees waiting). Keyless, live. The BTC counterpart to crypto.gas-oracle. It is categorised as a Read tool in the Mcp MCP Server, which means it retrieves data without modifying state.
Register the MCP server in PolicyLayer and add a rule for crypto.btc-fees: 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 Mcp. Nothing to install.
crypto.btc-fees 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 crypto.btc-fees 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 crypto.btc-fees. 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.
crypto.btc-fees is provided by the MCP server (@2sio/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 →