# list_postgresql_instances

Get a list of all PostgreSQL database instances

Agent View of the PolicyLayer registry record for `list_postgresql_instances`. HTML page: https://policylayer.com/tools/takashito-linode-mcp-server/list-postgresql-instances

## Facts

- Tool: `list_postgresql_instances`
- Server: Linode MCP Server (`takashito/linode-mcp-server`) — https://policylayer.com/tools/takashito-linode-mcp-server.md
- Homepage: https://github.com/takashito/linode-mcp-server
- Risk category: Read (Low risk)
- Registry record: grade F, 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_postgresql_instances",
    "arguments": {}
  }
}
```

## Why list_postgresql_instances is rated Low

This tool retrieves information about existing PostgreSQL instances without creating, modifying, deleting, or executing any operations. It is a straightforward read operation that returns data inventory. The blast radius if misused by an AI agent is minimal—exposure of database instance metadata could pose some information disclosure risk, but the operation itself is non-destructive and non-operational.

From the tool's own definition: "Tool name 'list_postgresql_instances' and description 'Get a list of all PostgreSQL database instances' indicate a retrieval/query operation with no side effects."

## Use case

AI agents call list_postgresql_instances to retrieve information from Linode 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 Linode MCP Server:

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

## Other tools on Linode MCP Server (415)

- `cancel_account` — Destructive — https://policylayer.com/tools/takashito-linode-mcp-server/cancel-account.md
- `cancel_backups` — Destructive — https://policylayer.com/tools/takashito-linode-mcp-server/cancel-backups.md
- `cancel_object_storage` — Destructive — https://policylayer.com/tools/takashito-linode-mcp-server/cancel-object-storage.md
- `delete_alert_definition` — Destructive — https://policylayer.com/tools/takashito-linode-mcp-server/delete-alert-definition.md
- `delete_api_token` — Destructive — https://policylayer.com/tools/takashito-linode-mcp-server/delete-api-token.md
- `delete_config_interface` — Destructive — https://policylayer.com/tools/takashito-linode-mcp-server/delete-config-interface.md
- `delete_domain` — Destructive — https://policylayer.com/tools/takashito-linode-mcp-server/delete-domain.md
- `delete_domain_record` — Destructive — https://policylayer.com/tools/takashito-linode-mcp-server/delete-domain-record.md
- `delete_firewall` — Destructive — https://policylayer.com/tools/takashito-linode-mcp-server/delete-firewall.md
- `delete_firewall_device` — Destructive — https://policylayer.com/tools/takashito-linode-mcp-server/delete-firewall-device.md
- `delete_image` — Destructive — https://policylayer.com/tools/takashito-linode-mcp-server/delete-image.md
- `delete_image_sharegroup` — Destructive — https://policylayer.com/tools/takashito-linode-mcp-server/delete-image-sharegroup.md
- `delete_instance` — Destructive — https://policylayer.com/tools/takashito-linode-mcp-server/delete-instance.md
- `delete_instance_config` — Destructive — https://policylayer.com/tools/takashito-linode-mcp-server/delete-instance-config.md
- `delete_instance_disk` — Destructive — https://policylayer.com/tools/takashito-linode-mcp-server/delete-instance-disk.md
- `delete_ipv4_address` — Destructive — https://policylayer.com/tools/takashito-linode-mcp-server/delete-ipv4-address.md
- `delete_ipv6_range` — Destructive — https://policylayer.com/tools/takashito-linode-mcp-server/delete-ipv6-range.md
- `delete_kubernetes_cluster` — Destructive — https://policylayer.com/tools/takashito-linode-mcp-server/delete-kubernetes-cluster.md
- `delete_kubernetes_control_plane_acl` — Destructive — https://policylayer.com/tools/takashito-linode-mcp-server/delete-kubernetes-control-plane-acl.md
- `delete_kubernetes_kubeconfig` — Destructive — https://policylayer.com/tools/takashito-linode-mcp-server/delete-kubernetes-kubeconfig.md
- `delete_kubernetes_node` — Destructive — https://policylayer.com/tools/takashito-linode-mcp-server/delete-kubernetes-node.md
- `delete_kubernetes_node_pool` — Destructive — https://policylayer.com/tools/takashito-linode-mcp-server/delete-kubernetes-node-pool.md
- `delete_kubernetes_service_token` — Destructive — https://policylayer.com/tools/takashito-linode-mcp-server/delete-kubernetes-service-token.md
- `delete_linode_interface` — Destructive — https://policylayer.com/tools/takashito-linode-mcp-server/delete-linode-interface.md
- `delete_log_destination` — Destructive — https://policylayer.com/tools/takashito-linode-mcp-server/delete-log-destination.md
- `delete_log_stream` — Destructive — https://policylayer.com/tools/takashito-linode-mcp-server/delete-log-stream.md
- `delete_longview_client` — Destructive — https://policylayer.com/tools/takashito-linode-mcp-server/delete-longview-client.md
- `delete_mysql_instance` — Destructive — https://policylayer.com/tools/takashito-linode-mcp-server/delete-mysql-instance.md
- `delete_nodebalancer` — Destructive — https://policylayer.com/tools/takashito-linode-mcp-server/delete-nodebalancer.md
- `delete_notification_channel` — Destructive — https://policylayer.com/tools/takashito-linode-mcp-server/delete-notification-channel.md
- …and 385 more: https://policylayer.com/tools/takashito-linode-mcp-server.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=takashito-linode-mcp-server · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/takashito-linode-mcp-server