Run SELECT and other read-only SQL queries on the connected database. This tool only accepts non-destructive queries (SELECT, SHOW, DESCRIBE, EXPLAIN).
AI agents call query_read to retrieve information from MCP Universal DB Client without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
This tool is strictly limited to read-only operations that retrieve or query data without any side effects. The explicit whitelist of allowed query types (SELECT, SHOW, DESCRIBE, EXPLAIN) and prohibition on destructive queries confirms it performs no data modification, deletion, or irreversible actions. Even if an AI misuses this tool, it cannot cause data loss or modification.
From the tool's definition Tool name 'query_read' and description explicitly states 'Run SELECT and other read-only SQL queries' and 'only accepts non-destructive queries (SELECT, SHOW, DESCRIBE, EXPLAIN)'
Attacks that exploit this kind of access
Run SELECT and other read-only SQL queries on the connected database. This tool only accepts non-destructive queries (SELECT, SHOW, DESCRIBE, EXPLAIN). It is categorised as a Read tool in the MCP Universal DB Client MCP Server, which means it retrieves data without modifying state.
Register the MCP Universal DB Client MCP server in PolicyLayer and add a rule for query_read: 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 Universal DB Client. Nothing to install.
query_read 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_read 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_read. 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_read is provided by the MCP Universal DB Client MCP server (izumisy/mcp-universal-db-client). 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 →