List all tables in a BigQuery dataset with their schemas. Uses INFORMATION_SCHEMA for efficiency. Use this to understand what tables and columns are available before writing queries.
AI agents call list_tables to retrieve information from BigQuery MCP Server without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
This tool purely retrieves and enumerates metadata about database structure (table names and schemas). It performs no modifications, deletions, code execution, or financial operations. The blast radius of misuse is minimal—an agent could discover what data exists, but cannot access the actual data, modify it, or trigger external operations. This is a straightforward data discovery/Read operation.
From the tool's definition Tool description states it 'List[s] all tables in a BigQuery dataset with their schemas' and 'Use this to understand what tables and columns are available before writing queries.' The mechanism is querying INFORMATION_SCHEMA, which is a metadata catalog query…
Documented attack patterns abuse exactly the kind of access list_tables gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and BigQuery MCP Server, and nothing reaches the server without passing your rules. This is the rule we recommend for list_tables:
{
"version": "1",
"default": "deny",
"tools": {
"list_tables": {}
}
}list_tables is read-only, so it stays allowed — but everything else on the server is denied unless you say otherwise.
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List all tables in a BigQuery dataset with their schemas. Uses INFORMATION_SCHEMA for efficiency. Use this to understand what tables and columns are available before writing queries. It is categorised as a Read tool in the BigQuery MCP Server MCP Server, which means it retrieves data without modifying state.
Register the BigQuery MCP Server MCP server in PolicyLayer and add a rule for list_tables: 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 BigQuery MCP Server. Nothing to install.
list_tables 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 list_tables 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 list_tables. 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.
list_tables is provided by the BigQuery MCP Server MCP server (suganthan-mohanadasan/suganthans-bigquery-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Deterministic rules across all 32 BigQuery MCP Server tools. Per-identity grants. Full audit log. Live in minutes. Nothing to install.
Free to start. No card required.
32 BigQuery MCP Server tools catalogued and risk-classified — across an index of 42,500+ MCP servers.