libcal_list_calendars

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

With no annotations provided, the description carries the behavioral burden. The verb 'List' clearly indicates a read-only operation with no destructive side effects, and the config.json reference provides useful context about where the result is consumed. It does not spell out authentication requirements, but for a simple listing tool the implied read-only nature is sufficient.

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 a single, efficient sentence that front-loads the action and resource, then appends the one essential usage hint. There is no filler or redundancy.

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, no-output-schema tool, the description fully covers what the tool does and why the agent would call it. It tells the agent the output (calendar names) and how to use it, making it complete enough for correct invocation.

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, so parameter semantics are largely not applicable; the baseline for zero parameters is 4. The description adds value by explaining how the output relates to config.json, which is more than the empty schema provides.

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 states a clear, specific action ('List') and resource ('Apple Calendar calendar names'), which is immediately distinct from the sibling tools that check availability, book, authenticate, or suggest. It also tells the agent the practical outcome, selecting a name for config.json, so the purpose is unambiguous.

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?

The parenthetical 'use one in ~/.unc-libcal/config.json as calendarName' implies when the tool is needed (before configuring a calendar) and how its output should be used. However, it does not explicitly state when to use this tool instead of a sibling, nor does it provide exclusions or prerequisites.

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