browse_databases

THE RISK

Low Risk

Why browse_databases needs a policy

This tool only enumerates available database files in a directory—a passive information-gathering operation with no side effects, no code execution, and no data modification. It poses minimal risk as it cannot alter state or trigger operations beyond directory listing.

From the tool's definition Tool name 'browse_databases' and description 'Browse and list available DuckDB database files in a directory' indicate a read-only operation that retrieves or queries information without modifying data or triggering external operations.

Documented attack patterns abuse exactly the kind of access browse_databases gives an agent:

POLICY

How to control browse_databases

PolicyLayer is an MCP gateway — it sits between your AI agents and MCP Data Visualization Server, and nothing reaches the server without passing your rules. This is the rule we recommend for browse_databases:

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "browse_databases": {}
  }
}

browse_databases is read-only, so it stays allowed — but everything else on the server is denied unless you say otherwise.

Create a free account and register MCP Data Visualization Server — nothing to install.
Add this policy — paste it, or build it visually.
Point your MCP client (Claude, Cursor, anything) at your gateway URL.

CAP THIS TOOL →

Free to start. No card required.

EXPLORE

Related tools and policies

More MCP Data Visualization Server tools

Execute query_data Execute a SQL query on the database and return results Write change_database Connect to a different DuckDB database file Write load_csv_data Load CSV file into the database as a new table Write configure_chart Configure chart parameters by answering column selection questions Write create_interactive_dashboard Generate an interactive HTML dashboard with filtering controls and multiple visualizations Write create_sample_chart Create a sample chart for testing (useful for development) Write create_visualization Start creating a data visualization from natural language request Write select_database_by_number Select a database by its number from the browse results

All 28 MCP Data Visualization Server tools →

Read tools on other servers

M-Team MCP Server get_torrent_detail YouTube MCP Server search_channel Android Forensics ADB MCP Server parse_browser_history 0xarchive web3_challenge

Go deeper

The MCP Attack Database → Documented attack patterns against MCP deployments — and the policies that stop them.
Data exfiltration → How read access becomes an exfiltration channel when chained with untrusted content.
MCP token cost → What connecting this server costs in context-window tokens on every request.
Rate Limiting MCP Tool Calls: A Practical Guide →
MCP Security: Why Prompt Guardrails Aren't Enough →

FAQ

Questions about browse_databases

What does the browse_databases tool do? +

Browse and list available DuckDB database files in a directory. It is categorised as a Read tool in the MCP Data Visualization Server MCP Server, which means it retrieves data without modifying state.

How do I enforce a policy on browse_databases? +

Register the MCP Data Visualization Server MCP server in PolicyLayer and add a rule for browse_databases: 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 Data Visualization Server. Nothing to install.

What risk level is browse_databases? +

browse_databases is a Read tool with low risk. Read-only tools are generally safe to allow by default.

Can I rate-limit browse_databases? +

Yes. Add a rate_limit block to the browse_databases 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.

How do I block browse_databases completely? +

Set action: deny in the PolicyLayer policy for browse_databases. 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.

What MCP server provides browse_databases? +

browse_databases is provided by the MCP Data Visualization Server MCP server (xoniks/mcp-visualization-duckdb). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

Enforce policy on every MCP Data Visualization Server tool call.

Start from MCP Data Visualization Server, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.

CHECK YOUR STACK →