ha_list_calendarsList all calendar entities in a Home Assistant instance and return each calendar's entity ID and name, so AI clients can identify available calendars.
Calendar entities available in this instance. Args: none. Returns entity_id and name.
| Name | Required | Description | Default |
|---|---|---|---|
No arguments | |||
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, so the safety profile is covered. The description adds 'Args: none' and the return fields, which is useful but minimal; with no output schema this return-shape note carries some weight, though it stops at two field names.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
Three terse fragments, no waste, and the resource scope is front-loaded. 'Args: none' is mildly redundant against the empty schema but harmless.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a zero-parameter read tool with full annotation coverage and no output schema, the description supplies the essentials: what it returns and that it needs no input. Only the relationship to ha_get_calendar_events is left unstated.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
The tool takes zero parameters, so the baseline is 4. 'Args: none' explicitly confirms the schema's empty properties, leaving no ambiguity for the caller.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description names the resource ('Calendar entities available in this instance') and implies enumeration, but there is no verb and no explicit differentiation from siblings such as ha_get_calendar_events. An agent can infer it lists calendars, but the definition relies on the tool name to supply the action.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
It never states when to use this tool versus alternatives, nor any prerequisite (e.g. call this to discover entity_ids before ha_get_calendar_events). Usage is only implied by the return fields.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.