Execute SELECT query
AI agents call query_database to retrieve information from PostgreSQL MCP Server without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
The tool executes SELECT queries against a PostgreSQL database. The server description explicitly states read-only access, limiting this to data retrieval. However, severity is medium because even read-only SQL access could expose sensitive data if misused, and there's some risk that the SELECT query interface could be abused with complex subqueries or functions depending on enforcement.
From the tool's definition Tool name 'query_database' with description 'Execute SELECT query'; server description states 'read-only access with automatic row limits'
Attacks that exploit this kind of access
Execute SELECT query. It is categorised as a Read tool in the PostgreSQL MCP Server MCP Server, which means it retrieves data without modifying state.
Register the PostgreSQL MCP Server MCP server in PolicyLayer and add a rule for query_database: 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 PostgreSQL MCP Server. Nothing to install.
query_database 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 query_database 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 query_database. 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.
query_database is provided by the PostgreSQL MCP Server MCP server (psreekrishnan/postgresql-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 →