List Calendars

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

The annotations already indicate readOnly, openWorld, idempotent, and non-destructive behavior, so the description does not need to restate safety. It adds value by clarifying that the listing is scoped to the authenticated user, which is meaningful context beyond the structured annotations. The output schema covers return details, reducing the need for further description.

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 concise sentence that directly states the tool's function without any filler. It is front-loaded with the action and resource, making it easy for an agent to quickly grasp the purpose. Every word contributes meaning.

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 simple list operation with one required parameter, full schema coverage, and an output schema, the description is largely sufficient. It correctly identifies the resource and the scope of results. It could be slightly more complete by noting any pagination or ordering behavior, but given the strong annotations and schema support, no critical information is missing.

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 input schema has 100% parameter description coverage, with user_google_email clearly described as the user's Google email address and required. The tool description adds no additional semantic detail about the parameter beyond what the schema already provides. The baseline score of 3 is appropriate when the schema carries the full documentation load.

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 tool's action ('Retrieves a list') and resource ('calendars'), using a specific verb and object. It also adds a scoping detail ('accessible to the authenticated user'). However, it does not explicitly differentiate itself from sibling tools like create_calendar, though the verb and noun make the distinction reasonably clear.

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 implies that this tool is for listing existing calendars, which indirectly distinguishes it from create_calendar and event-focused tools. There is no explicit guidance on when to choose this over alternatives, nor any mention of prerequisites like authentication state. The usage context is only implied by the nature of the operation.

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