List ChurchTools calendars

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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds substantive context beyond that: results are permission-scoped to calendars visible to the calling user, and the returned shape (id, name, visibility) is disclosed despite there being no output schema.

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?

A single clause-length sentence that front-loads the action and scope, then lists the payload. Every element earns its place with no filler or repetition of the title.

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 annotations covering safety and no output schema, the description supplies enough: scope, permission bound, and returned fields. Only minor gaps remain, such as ordering or whether calendars include ones merely subscribed to.

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 rule-of-thumb baseline of 4 applies. There is nothing parameter-wise for the description to compensate for, and the field list it provides describes the response rather than inputs.

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 specific verb and resource ('Lists every calendar') and enumerates the returned fields (id, name, visibility). There is no calendar-related sibling among the tools, so differentiation is largely unnecessary, though it never explicitly positions itself against the other ct_list_* tools.

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?

Usage is implied by the scope phrase 'every calendar the user can see', which tells the agent this is the unfiltered listing for calendars. It gives no explicit when-to-use/when-not guidance or prerequisites, but with zero parameters and no obvious alternative tool, the implied context is adequate.

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