List calendars

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

Even though annotations already declare readOnlyHint, idempotentHint, and destructiveHint, the description adds meaningful behavior beyond those: pagination via nextPageToken, hidden/selected flags, accessRole semantics for write permissions, and the important limitation that shared-but-unadded calendars are not returned. No annotation contradiction exists.

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 compact yet information-dense. It front-loads the core purpose and return fields, then adds the primary-id shortcut, pagination, and edge-case behavior in logical order. Every sentence earns its place; there is no filler or repetition of schema details.

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 there is no output schema, the description fully compensates by enumerating the returned fields, explaining role semantics, pagination, and the special 'primary' id. It also covers the key edge case of shared calendars not appearing in the list. An agent has enough context to invoke the tool correctly and interpret its results.

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?

Schema coverage is 100%, so the schema already documents all four parameters. The description adds extra value by linking accessRole values to write permissions ('writes need writer or owner'), which clarifies the intent of min_access_role, and by explaining how page_token connects to nextPageToken. This goes slightly beyond a baseline schema-only understanding.

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 action and resource: 'Lists the calendars on the user's calendar list' and enumerates the exact fields returned. It further distinguishes this tool from get_calendar by explaining what is absent (shared calendars never added to the list) and how to address them.

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 description gives concrete when-to-use and when-not-to-use guidance: the 'primary' special id removes the need to call this tool for the main calendar, and calendars not on the user's list must be addressed by explicit id instead. This helps the agent choose list_calendars versus get_calendar without ambiguity.

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