# save_energy_prefs

Save Energy Dashboard preferences (WS energy/save_prefs); only the fields you pass are sent.

Agent View of the PolicyLayer registry record for `save_energy_prefs`. HTML page: https://policylayer.com/tools/fistacho-ha-nexus-agent/save-energy-prefs

## Facts

- Tool: `save_energy_prefs`
- 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: Write (Medium risk)
- Registry record: grade F, identity unverified
- Server rate-limited: no
- Parameters: 0
- Recommended policy verdict: Rate-limited

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

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

## Why save_energy_prefs is rated Medium

This tool modifies user configuration/preferences data for the Energy Dashboard in Home Assistant. It is reversible (preferences can be changed again), making it a Write operation rather than Destructive. Severity is medium because incorrect energy preference changes could affect energy monitoring, reporting, or automation logic, but would not directly control critical home systems or cause data loss.

From the tool's own definition: "Tool name 'save_energy_prefs' and description 'Save Energy Dashboard preferences' indicates creation or modification of user preference data. The mechanism uses WebSocket endpoint `energy/save_prefs` which persists preference state."

## Use case

AI agents use save_energy_prefs to create or update resources in Ha Nexus Agent, usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Ha Nexus Agent environment.

## Recommended policy (PolicyLayer)

Verdict: **Rate-limited**. Enforced by the PolicyLayer MCP gateway (https://policylayer.com/mcp-gateway) before a call reaches Ha Nexus Agent:

```json
{
  "version": "1",
  "default": "deny",
  "tools": {
    "save_energy_prefs": {
      "limits": [
        {
          "counter": "save_energy_prefs_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}
```

## 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`

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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
