Introspect database schema
AI agents call schema to retrieve information from MCP Server Templates without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
Schema introspection is a non-destructive query operation that only retrieves metadata about database structure. It has no side effects and cannot alter data or execute code. The blast radius of misuse is minimal—an agent could learn database structure but cannot modify, delete, or extract sensitive data beyond what schema names reveal.
From the tool's definition Tool name 'schema' and description 'Introspect database schema' indicate a read-only operation that retrieves schema metadata without modifying or executing queries.
Attacks that exploit this kind of access
Introspect database schema. It is categorised as a Read tool in the MCP Server Templates MCP Server, which means it retrieves data without modifying state.
Register the MCP Server Templates MCP server in PolicyLayer and add a rule for schema: 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 Server Templates. Nothing to install.
schema 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 schema 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 schema. 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.
schema is provided by the MCP Server Templates MCP server (visystems/mcp-server-templates). 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 →