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List helpers

list_helpers

Read-onlyIdempotent

Lists UI-managed Home Assistant helpers by type—input booleans, numbers, texts, selects, datetimes, buttons, counters, timers, schedules—to identify editable helpers; YAML-defined helpers excluded.

Instructions

List UI managed helpers (input_boolean, input_number, input_text, input_select, input_datetime, input_button, counter, timer, schedule). Helpers defined in YAML are not editable through the API and are not listed here.

Tool call template

This tool declares no required parameters. Add optional parameters from the input schema as needed.

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

Input Schema

Name	Required	Description	Default
`helper_type`	No	Restrict to one helper type. Omit to list all types.

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.2.1Nov 5, 2026

TDQS

A3.7/5.0

Behavior4/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and a closed world, so the safety profile is covered. The description adds genuinely new behavioral context beyond that: YAML-defined helpers are excluded from results and are not editable through the API, which prevents an agent from misreading a partial list as a complete inventory.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Two short sentences with the capability front-loaded and the exclusion caveat second; nothing is padded. The inline type list is somewhat redundant with the enum in the schema, costing a little length without new information.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a single-optional-parameter read tool with rich annotations, the description covers what is listed, what is excluded, and why. The only gap is that no output schema exists and the description does not describe the shape of returned helper objects, which is a minor omission rather than a blocker.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100% and the single optional parameter has a fully documented enum with an explicit 'omit to list all types' note. The description's enumeration of helper types largely restates the enum rather than adding format, alias, or defaulting semantics, so baseline 3 applies.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description gives a specific verb (list) and resource (UI managed helpers) and enumerates exactly which helper domains are covered, so an agent knows precisely what comes back. It stops short of distinguishing this from siblings such as search_entities or list_registry, which also enumerate entity-like objects, so it is clear but not fully disambiguating.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines3/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Usage is implied by the scope statement: use this to enumerate UI-managed helpers, and by extension don't expect YAML-defined ones. There is no explicit when-to-use or when-not-to-use guidance and no named alternative for an agent that actually wants YAML helpers or wants to search across all entities.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.