BetterDB MCP

Instructions

Implementation Reference

• packages/mcp/src/index.ts:546-566 (handler)

  The 'get_hot_keys' tool is registered and implemented directly in the MCP server setup within packages/mcp/src/index.ts. It executes a network request to the API via 'apiFetch' to fetch the hot key data.

  server.tool(
    'get_hot_keys',
    'Get hot key tracking data from persisted storage. BetterDB periodically scans keys using LFU frequency scores (when maxmemory-policy is an LFU variant) or OBJECT IDLETIME / COMMANDLOG-derived frequency. Each snapshot captures the top keys ranked by access frequency. Use this to find cache-busting keys, uneven access patterns, or keys that dominate throughput. The signalType field in each entry indicates which detection mode was active (lfu or idletime).',
    {
      startTime: z.number().optional().describe('Start time (Unix timestamp ms)'),
      endTime: z.number().optional().describe('End time (Unix timestamp ms)'),
      limit: z.number().optional().describe('Max entries to return (default 50, max 200)'),
      instanceId: z.string().optional().describe('Optional instance ID override'),
    },
    async ({ startTime, endTime, limit, instanceId }) => {
      const id = resolveInstanceId(instanceId);
      const qs = buildQuery({ startTime, endTime, limit });
      const data = await apiFetch(`/mcp/instance/${id}/hot-keys${qs}`);
      if (isLicenseError(data)) {
        return { content: [{ type: 'text' as const, text: licenseErrorResult(data) }] };
      }
      return {
        content: [{ type: 'text' as const, text: JSON.stringify(data, null, 2) }],
      };
    },
  );