Get the definition and columns of a view.
AI agents call describe_view to retrieve information from Postgres without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
This tool retrieves metadata about a PostgreSQL view (its definition and column structure) without modifying data, executing code, or triggering side effects. It is a read-only introspection operation, consistent with similar metadata tools on this server like describe_table, list_schemas, and list_tables.
From the tool's definition Tool name 'describe_view' and description 'Get the definition and columns of a view' indicate a pure retrieval operation with no data modification or execution.
Documented attack patterns abuse exactly the kind of access describe_view gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and Postgres, and nothing reaches the server without passing your rules. This is the rule we recommend for describe_view:
{
"version": "1",
"default": "deny",
"tools": {
"describe_view": {}
}
}describe_view is read-only, so it stays allowed — but everything else on the server is denied unless you say otherwise.
Free to start. No card required.
Get the definition and columns of a view. It is categorised as a Read tool in the Postgres MCP Server, which means it retrieves data without modifying state.
Register the Postgres MCP server in PolicyLayer and add a rule for describe_view: 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 Postgres. Nothing to install.
describe_view 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 describe_view 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 describe_view. 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.
describe_view is provided by the Postgres MCP server (javimaligno/postgres_mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Start from Postgres, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.
Free to start. No card required.
14 Postgres tools catalogued and risk-classified — across an index of 43,000+ MCP servers.