# list_databases

List catalogs/databases for one backend.

Agent View of the PolicyLayer registry record for `list_databases`. HTML page: https://policylayer.com/tools/1249zts-db-mcp-service/list-databases

## Facts

- Tool: `list_databases`
- Server: Multi-DB MCP Server (`1249zts/db-mcp-service`) — https://policylayer.com/tools/1249zts-db-mcp-service.md
- Homepage: https://github.com/1249zts/db-mcp-service
- Risk category: Read (Low risk)
- Registry record: grade C, identity unverified
- Server rate-limited: no
- Parameters: 0
- Recommended policy verdict: Allowed

## Example call (MCP tools/call, JSON-RPC 2.0)

```json
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "list_databases",
    "arguments": {}
  }
}
```

## Why list_databases is rated Low

This tool queries database metadata (available databases/catalogs) without performing any write, execute, or destructive operations. It is a read-only information retrieval function with minimal risk. Severity is low because the blast radius of misuse is limited to information disclosure of database names, which are typically not sensitive enough to warrant higher severity in most contexts.

From the tool's own definition: "Tool name 'list_databases' and description 'List catalogs/databases for one backend' indicate a retrieval operation with no modification or deletion of data."

## Use case

AI agents call list_databases to retrieve information from Multi-DB MCP Server without modifying anything. It is typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.

## Recommended policy (PolicyLayer)

Verdict: **Allowed**. Enforced by the PolicyLayer MCP gateway (https://policylayer.com/mcp-gateway) before a call reaches Multi-DB MCP Server:

```json
{
  "version": "1",
  "default": "deny",
  "tools": {
    "list_databases": {}
  }
}
```

## Other tools on Multi-DB MCP Server (4)

- `execute_sql` — Execute — https://policylayer.com/tools/1249zts-db-mcp-service/execute-sql.md
- `describe_table` — Read — https://policylayer.com/tools/1249zts-db-mcp-service/describe-table.md
- `list_enabled_databases` — Read — https://policylayer.com/tools/1249zts-db-mcp-service/list-enabled-databases.md
- `list_tables` — Read — https://policylayer.com/tools/1249zts-db-mcp-service/list-tables.md

## For agents

This record is a snapshot. Live verdicts and the full registry:

- Check every server in your MCP config at once: `npx -y policylayer stack`
- Vet a server before you add it: install the mcp-precheck skill — `npx skills add https://policylayer.com` (skill text: https://policylayer.com/skill.md)
- Query the registry over MCP: endpoint `https://api.policylayer.com/mcp` — tools `check_mcp_server`, `check_mcp_stack`, `check_tool`, `search_registry`, `get_change_events`

---

Source: the PolicyLayer MCP registry — one continuously verified record per MCP server. Full record: https://policylayer.com/registry?q=1249zts-db-mcp-service · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/1249zts-db-mcp-service