Calendar List Calendars

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

The description adds no behavioral context beyond the annotations already provided. 'Delegated Apple domain tool' is generic boilerplate and does not disclose what the operation returns, its scope, or any side effects. It does not contradict the readOnlyHint or idempotentHint, but it also contributes nothing.

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?

The description is short, but it spends its single sentence restating the tool name and platform instead of explaining functionality. This is under-specification rather than genuinely concise, useful writing.

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?

The tool is simple: no parameters, read-only, idempotent, and has an output schema. However, the description still fails to state the core purpose, so an agent must rely entirely on the tool name to infer what it does. Minimal but necessary context is missing.

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 has zero parameters, and the schema already makes this clear with an empty properties object. There is no parameter behavior for the description to explain, so the baseline of 4 is appropriate.

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 merely restates the tool name and says it is 'exposed through Apple-Tools-MCP'; it never states that the tool lists calendars. This is essentially a tautology that provides no verb, resource, or functional meaning beyond the name itself.

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?

There is no guidance about when to use this tool, what problem it solves, or how it differs from related sibling tools like calendar_list_events or calendar_health. The agent is given no selection criteria.

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