# list_css_custom_properties List CSS custom properties (@property registrations). Agent View of the PolicyLayer registry record for `list_css_custom_properties`. HTML page: https://policylayer.com/tools/fistacho-ha-nexus-agent/list-css-custom-properties ## Facts - Tool: `list_css_custom_properties` - 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_css_custom_properties", "arguments": {} } } ``` ## Why list_css_custom_properties is rated Low This tool queries or retrieves CSS custom property registrations from the Home Assistant UI configuration. It performs data retrieval only, with no ability to modify, delete, or execute operations. The blast radius of misuse is minimal—an AI could at worst enumerate CSS properties but cannot alter system state, trigger automations, or control devices. From the tool's own definition: "Tool name contains 'list' and description states 'List CSS custom properties' — a retrieval operation with no side effects." ## Use case AI agents call list_css_custom_properties 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_css_custom_properties": {} } } ``` ## 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