# list_calendars

List all calendar entities (REST: GET /api/calendars).

Agent View of the PolicyLayer registry record for `list_calendars`. HTML page: https://policylayer.com/tools/fistacho-ha-nexus-agent/list-calendars

## Facts

- Tool: `list_calendars`
- Server: Ha Nexus Agent (`fistacho/ha-nexus-agent`) — https://policylayer.com/tools/fistacho-ha-nexus-agent.md
- Homepage: https://github.com/Fistacho/ha-nexus-agent
- 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_calendars",
    "arguments": {}
  }
}
```

## Why list_calendars is rated Low

This tool retrieves calendar information from Home Assistant without creating, modifying, deleting, or executing operations. It is purely informational. The GET HTTP method and 'list' operation confirm it is a Read category tool. Severity is low because exposure of calendar entity names poses minimal direct risk, though calendar details could include scheduling information worth protecting.

From the tool's own definition: "Tool description states 'List all calendar entities (REST: GET /api/calendars)' — uses GET method, performs a list/query operation with no modification or side effects."

## Use case

AI agents call list_calendars to retrieve information from Ha Nexus Agent 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 Ha Nexus Agent:

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

## Other tools on Ha Nexus Agent (275)

- `abort_config_flow` — Destructive — https://policylayer.com/tools/fistacho-ha-nexus-agent/abort-config-flow.md
- `abort_options_flow` — Destructive — https://policylayer.com/tools/fistacho-ha-nexus-agent/abort-options-flow.md
- `delete_area` — Destructive — https://policylayer.com/tools/fistacho-ha-nexus-agent/delete-area.md
- `delete_automation` — Destructive — https://policylayer.com/tools/fistacho-ha-nexus-agent/delete-automation.md
- `delete_backup` — Destructive — https://policylayer.com/tools/fistacho-ha-nexus-agent/delete-backup.md
- `delete_blueprint` — Destructive — https://policylayer.com/tools/fistacho-ha-nexus-agent/delete-blueprint.md
- `delete_card` — Destructive — https://policylayer.com/tools/fistacho-ha-nexus-agent/delete-card.md
- `delete_category` — Destructive — https://policylayer.com/tools/fistacho-ha-nexus-agent/delete-category.md
- `delete_config_file` — Destructive — https://policylayer.com/tools/fistacho-ha-nexus-agent/delete-config-file.md
- `delete_css_custom_property` — Destructive — https://policylayer.com/tools/fistacho-ha-nexus-agent/delete-css-custom-property.md
- `delete_event` — Destructive — https://policylayer.com/tools/fistacho-ha-nexus-agent/delete-event.md
- `delete_label` — Destructive — https://policylayer.com/tools/fistacho-ha-nexus-agent/delete-label.md
- `delete_media` — Destructive — https://policylayer.com/tools/fistacho-ha-nexus-agent/delete-media.md
- `delete_pipeline` — Destructive — https://policylayer.com/tools/fistacho-ha-nexus-agent/delete-pipeline.md
- `delete_script` — Destructive — https://policylayer.com/tools/fistacho-ha-nexus-agent/delete-script.md
- `delete_style_preset` — Destructive — https://policylayer.com/tools/fistacho-ha-nexus-agent/delete-style-preset.md
- `delete_theme` — Destructive — https://policylayer.com/tools/fistacho-ha-nexus-agent/delete-theme.md
- `delete_zone` — Destructive — https://policylayer.com/tools/fistacho-ha-nexus-agent/delete-zone.md
- `git_rollback_file` — Destructive — https://policylayer.com/tools/fistacho-ha-nexus-agent/git-rollback-file.md
- `git_rollback_to_commit` — Destructive — https://policylayer.com/tools/fistacho-ha-nexus-agent/git-rollback-to-commit.md
- `notify_persistent_dismiss` — Destructive — https://policylayer.com/tools/fistacho-ha-nexus-agent/notify-persistent-dismiss.md
- `notify_persistent_dismiss_all` — Destructive — https://policylayer.com/tools/fistacho-ha-nexus-agent/notify-persistent-dismiss-all.md
- `remove_device` — Destructive — https://policylayer.com/tools/fistacho-ha-nexus-agent/remove-device.md
- `remove_energy_source` — Destructive — https://policylayer.com/tools/fistacho-ha-nexus-agent/remove-energy-source.md
- `remove_integration` — Destructive — https://policylayer.com/tools/fistacho-ha-nexus-agent/remove-integration.md
- `remove_item` — Destructive — https://policylayer.com/tools/fistacho-ha-nexus-agent/remove-item.md
- `restore_backup` — Destructive — https://policylayer.com/tools/fistacho-ha-nexus-agent/restore-backup.md
- `stop_ha` — Destructive — https://policylayer.com/tools/fistacho-ha-nexus-agent/stop-ha.md
- `uninstall_addon` — Destructive — https://policylayer.com/tools/fistacho-ha-nexus-agent/uninstall-addon.md
- `uninstall_hacs_repository` — Destructive — https://policylayer.com/tools/fistacho-ha-nexus-agent/uninstall-hacs-repository.md
- …and 245 more: https://policylayer.com/tools/fistacho-ha-nexus-agent.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=fistacho-ha-nexus-agent · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/fistacho-ha-nexus-agent