list_calendars

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

No annotations provided, so description carries full burden. It discloses auth requirements (UAT, OAuth scope) and visibility limitation (app identity sees only invited calendars). Does not explicitly state it's read-only but the verb 'list' and scope 'readonly' imply no mutation.

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?

Two sentences: first states purpose, second states requirements. No unnecessary words, efficient and 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?

Covers purpose, auth, and parameter constraints. Lacks explanation of return format (no output schema) but that is acceptable. Adequate for a list tool with pagination and sync.

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?

Input schema has 100% coverage with descriptions. The tool description adds value by clarifying that page_size has a minimum of 50 and that the endpoint rejects smaller values, and explains sync_token as incremental. This goes beyond 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 the verb 'List' and the resource 'the current user's calendars (primary + shared + subscribed)'. It distinguishes from sibling tools like list_calendar_events by specifying it lists calendar objects, not events.

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 provides clear context for when to use by mentioning UAT requirement and scope. It does not explicitly list alternatives but implies this is for listing calendars vs events (sibling list_calendar_events). No exclusion criteria given.

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