Execute SELECT queries to read data from the database
AI agents call read_query to retrieve information from MCP Database Server without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
This tool is explicitly limited to SELECT queries, which have no side effects. While it executes SQL, it cannot modify, delete, or create data. The read-only constraint places it firmly in the Read category. Severity is low because data retrieval poses minimal risk even if an AI agent misuses the tool — the worst case is unauthorized information access rather than data loss or system compromise.
From the tool's definition Tool name is 'read_query' and description states 'Execute SELECT queries to read data from the database' — SELECT queries are read-only operations that retrieve data without modification.
Attacks that exploit this kind of access
Execute SELECT queries to read data from the database. It is categorised as a Read tool in the MCP Database Server MCP Server, which means it retrieves data without modifying state.
Register the MCP Database Server MCP server in PolicyLayer and add a rule for read_query: 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 Database Server. Nothing to install.
read_query 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 read_query 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 read_query. 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.
read_query is provided by the MCP Database Server MCP server (juanyin1/mcp-database-server-with-database). 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.
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