# list_instances

List all Cloud SQL instances in the project.

Agent View of the PolicyLayer registry record for `list_instances`. HTML page: https://policylayer.com/tools/com-googleapis-sqladmin-mcp/list-instances

## Facts

- Tool: `list_instances`
- Server: Mcp (`https://sqladmin.googleapis.com/mcp`) — https://policylayer.com/tools/com-googleapis-sqladmin-mcp.md
- Homepage: https://github.com/https://sqladmin.googleapis.com/mcp
- Risk category: Read (Low risk)
- Registry record: grade F, identity unverified
- Server auth posture: open
- Server rate-limited: no
- Parameters: 5
- Recommended policy verdict: Allowed

## Parameters

| Parameter | Type | Required | Description |
| --- | --- | --- | --- |
| `filter` | string | no | A filter expression that filters resources listed in the response. The expression is in the form of field:value. For example, 'instanceType:CLOUD_SQL_INSTANCE'. |
| `project` | string | no | Project ID of the project for which to list Cloud SQL instances. |
| `location` | string | no | Optional. Region of the Cloud SQL instance. |
| `pageToken` | string | no | A previously-returned page token representing part of the larger set of results to view. |
| `maxResults` | integer | no | The maximum number of instances to return. The service may return fewer than this value. If unspecified, at most 500 instances are returned. The maximum value i |

Parameters from the server's own tool schema.

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

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

## Why list_instances is rated Low

Even though list_instances only reads data, uncontrolled read access leaks sensitive information and racks up API costs: an agent caught in a retry loop can make thousands of calls a minute without anyone noticing.

## Use case

AI agents call list_instances to retrieve information from Mcp 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 Mcp:

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

## Other tools on Mcp (14)

- `execute_sql` — Execute — https://policylayer.com/tools/com-googleapis-sqladmin-mcp/execute-sql.md
- `execute_sql_readonly` — Execute — https://policylayer.com/tools/com-googleapis-sqladmin-mcp/execute-sql-readonly.md
- `postgres_upgrade_precheck` — Execute — https://policylayer.com/tools/com-googleapis-sqladmin-mcp/postgres-upgrade-precheck.md
- `get_instance` — Read — https://policylayer.com/tools/com-googleapis-sqladmin-mcp/get-instance.md
- `get_operation` — Read — https://policylayer.com/tools/com-googleapis-sqladmin-mcp/get-operation.md
- `list_users` — Read — https://policylayer.com/tools/com-googleapis-sqladmin-mcp/list-users.md
- `clone_instance` — Write — https://policylayer.com/tools/com-googleapis-sqladmin-mcp/clone-instance.md
- `create_backup` — Write — https://policylayer.com/tools/com-googleapis-sqladmin-mcp/create-backup.md
- `create_instance` — Write — https://policylayer.com/tools/com-googleapis-sqladmin-mcp/create-instance.md
- `create_user` — Write — https://policylayer.com/tools/com-googleapis-sqladmin-mcp/create-user.md
- `import_data` — Write — https://policylayer.com/tools/com-googleapis-sqladmin-mcp/import-data.md
- `restore_backup` — Write — https://policylayer.com/tools/com-googleapis-sqladmin-mcp/restore-backup.md
- `update_instance` — Write — https://policylayer.com/tools/com-googleapis-sqladmin-mcp/update-instance.md
- `update_user` — Write — https://policylayer.com/tools/com-googleapis-sqladmin-mcp/update-user.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=com-googleapis-sqladmin-mcp · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/com-googleapis-sqladmin-mcp