update_theme

Update an existing theme file.

SERVERHa Nexus Agent SOURCEfistacho/ha-nexus-agent

Medium RISK CLASS

Category Write

Parameters 00 required

Recommended Rate-limitedsee the rule below

Registry record Grade F, identity unverified Pull the record →

This record as markdown: /tools/fistacho-ha-nexus-agent/update-theme.md

WHAT IT DOES

What update_theme does on Ha Nexus Agent

AI agents use update_theme 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.

RISK

Why update_theme is rated Medium

This tool modifies existing theme files in Home Assistant, which is a reversible write operation. While theme changes affect the visual presentation of the smart home interface, they do not delete data or cause destructive effects. However, misconfigured themes could make the interface unusable (medium severity).

From the tool's definition Tool name 'update_theme' and description 'Update an existing theme file' indicate modification of theme configuration data.

Attacks that exploit this kind of access

RECOMMENDED RULE

The rule that runs update_theme safely

PolicyLayer is an MCP gateway: it sits between your AI agents and Ha Nexus Agent, and checks every tool call against a rule you set before the call runs. Nothing changes on the server itself. For update_theme, this is the rule to start with:

update_theme Rate-limited

update_theme stays usable, but capped: an agent stuck in a loop can't make hundreds of changes a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "update_theme": {
      "limits": [
        {
          "counter": "update_theme_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

LIMIT THIS TOOL → Instant setup, no code required.

The button opens the PolicyLayer dashboard: create your workspace, connect Ha Nexus Agent, apply this rule, and every update_theme call is checked against it from then on.

FAQ

Questions about update_theme

What does the update_theme tool do? +

Update an existing theme file. It is categorised as a Write tool in the Ha Nexus Agent MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on update_theme? +

Register the Ha Nexus Agent MCP server in PolicyLayer and add a rule for update_theme: allow, deny, rate-limit, or require approval. Point your MCP client at the PolicyLayer proxy URL and the rule is enforced on every call, before it reaches Ha Nexus Agent. Nothing to install.

What risk level is update_theme? +

update_theme is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.

Can I rate-limit update_theme? +

Yes. Add a rate_limit block to the update_theme rule in your PolicyLayer policy. For example, setting max: 10 and window: 60 limits the tool to 10 calls per minute. Rate limits are tracked per agent session and reset automatically.

How do I block update_theme completely? +

Set action: deny in the PolicyLayer policy for update_theme. The AI agent will receive a policy violation error and cannot call the tool. You can also include a reason field to explain why the tool is blocked.

What MCP server provides update_theme? +

update_theme is provided by the Ha Nexus Agent MCP server (fistacho/ha-nexus-agent). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

KEEP EXPLORING

More on Ha Nexus Agent, and thousands of servers like it.

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All 276 Ha Nexus Agent tools →

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aroflo_create_or_update_record on AroFlo MCP →team_manager_update_budget on Team Manager MCP → The MCP Attack Database →

Guides

Govern customer-ops agents →Argument validation →Scoped token →