# list_instances

List information about instances in a project. The request requires the 'parent' field to be set in the format 'projects/{project}'. Example: { "parent": "projects/my-project" }

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

## Facts

- Tool: `list_instances`
- Server: Mcp (`https://bigtableadmin.googleapis.com/mcp`) — https://policylayer.com/tools/com-googleapis-bigtableadmin-mcp.md
- Homepage: https://github.com/https://bigtableadmin.googleapis.com/mcp
- Risk category: Read (Low risk)
- Registry record: grade F, identity unverified
- Server auth posture: open
- Server rate-limited: no
- Parameters: 2 (1 required)
- Recommended policy verdict: Allowed

## Parameters

| Parameter | Type | Required | Description |
| --- | --- | --- | --- |
| `parent` | string | yes | Required. The unique name of the project for which a list of instances is requested. Values are of the form `projects/{project}`. |
| `pageToken` | string | no | DEPRECATED: This field is unused and ignored. |

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": {
      "parent": "<parent>"
    }
  }
}
```

## Why list_instances is rated Low

This tool retrieves metadata about Bigtable instances scoped to a specific project. It performs a read-only query operation with no capability to modify, delete, or execute arbitrary code. The blast radius of misuse is minimal—an attacker gains visibility into instance configuration but cannot alter or destroy resources. Classification as 'Read' is appropriate.

From the tool's own definition: "Tool name 'list_instances' and description 'List information about instances in a project' indicate a retrieval operation with no side effects. The operation queries and returns data without modifying, creating, or deleting resources."

## 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 (13)

- `delete_instance` — Destructive — https://policylayer.com/tools/com-googleapis-bigtableadmin-mcp/delete-instance.md
- `delete_logical_view` — Destructive — https://policylayer.com/tools/com-googleapis-bigtableadmin-mcp/delete-logical-view.md
- `delete_table` — Destructive — https://policylayer.com/tools/com-googleapis-bigtableadmin-mcp/delete-table.md
- `get_instance` — Read — https://policylayer.com/tools/com-googleapis-bigtableadmin-mcp/get-instance.md
- `get_logical_view` — Read — https://policylayer.com/tools/com-googleapis-bigtableadmin-mcp/get-logical-view.md
- `get_table` — Read — https://policylayer.com/tools/com-googleapis-bigtableadmin-mcp/get-table.md
- `list_hot_tablets` — Read — https://policylayer.com/tools/com-googleapis-bigtableadmin-mcp/list-hot-tablets.md
- `list_logical_views` — Read — https://policylayer.com/tools/com-googleapis-bigtableadmin-mcp/list-logical-views.md
- `list_tables` — Read — https://policylayer.com/tools/com-googleapis-bigtableadmin-mcp/list-tables.md
- `create_instance` — Write — https://policylayer.com/tools/com-googleapis-bigtableadmin-mcp/create-instance.md
- `create_logical_view` — Write — https://policylayer.com/tools/com-googleapis-bigtableadmin-mcp/create-logical-view.md
- `create_table` — Write — https://policylayer.com/tools/com-googleapis-bigtableadmin-mcp/create-table.md
- `update_logical_view` — Write — https://policylayer.com/tools/com-googleapis-bigtableadmin-mcp/update-logical-view.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-bigtableadmin-mcp · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/com-googleapis-bigtableadmin-mcp