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

Annotations already indicate readOnlyHint=false and destructiveHint=false, so the description is not required to restate safety. However, it adds little beyond the schema: 'optional settings' is already evident from the input schema. It does not disclose side effects (e.g., whether creation requires authentication, whether it overwrites anything, or what happens on duplicate names).

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 one short, direct sentence that front-loads the primary action. It contains no filler or redundant information, and every word earns its place.

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 the tool has 10 parameters and no output schema, the description is somewhat sparse. It doesn't mention the return value (e.g., created calendar object) or any behavioral implications of the settings. However, the schema covers parameter semantics well, so the missing return-value note is a gap but not catastrophic.

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 description coverage is 100%, with each parameter having a descriptive comment. The description's phrase 'optional settings' adds no specific semantics beyond what the schema already provides, so the baseline of 3 is appropriate; it does not compensate or add additional meaning.

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 'Create a new booking calendar with optional settings' uses a specific verb ('create') and resource ('booking calendar'), clearly distinguishing it from sibling tools like create_calendar_override or create_contact. It accurately conveys the core action.

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 usage (when you need a new calendar) but gives no explicit when-to-use vs alternatives, no exclusions, and no prerequisites. It doesn't mention that this is for initial calendar setup, while update_calendar would be for modifying an existing one, which would be useful context.

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