list_calendars

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

No annotations are provided, so the description carries the full burden. It discloses the default env var behavior, override semantics, and the specific return fields (calendar id, alias_code, name, category, subscription count, label palette). It omits potential error conditions, but for a list tool this is reasonably transparent.

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 sentences with zero filler. The first sentence states the core function, and subsequent sentences add essential configuration context and return format. Efficiently front-loaded.

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?

Given no output schema, the description lists the returned fields, covering what the agent needs to know. It explains default and override paths. It doesn't mention prerequisites or error behavior, but for a simple list tool this is largely complete.

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 schema already covers alias_codes with a description, and the schema coverage is 100%. The description adds value by providing the URL template (https://timetr.ee/p/<code>) and clarifying that it overrides the env var, enriching the parameter semantics beyond the schema.

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 clearly states 'List configured TimeTree public calendars' with a specific verb and resource. It distinguishes from sibling tools like list_events by focusing on calendar listing, and explains the default vs override behavior.

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 explains when to use: without args it uses the TIMETREE_CALENDAR_ALIASES env var, and how to override with alias_codes, including the URL format for codes. No explicit alternatives are mentioned, but sibling tools are clearly event-related, making the context obvious.

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