create_virtual_member

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

Annotations already cover the safety profile (non-destructive, open-world, non-idempotent). The description adds real behavioral context beyond them: the member is visible to everyone in the calendar, and there's a hard cap of 10 per calendar. It stops short of auth requirements, but the visibility and quota disclosures are genuinely useful.

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 tightly-packed sentences, front-loaded with what the tool does and the concept, then visibility, then the quota, then the return value. Every sentence earns its place with no waste.

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?

Output schema exists and the description still briefly notes the returned id/uuid. Combined with full schema coverage and annotations, an agent has everything needed to call this correctly — the concept, constraints, and side effects are all present.

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 six parameters including the type enum and birthday format. The description adds conceptual context (linking to virtual_user_attendees) but no parameter-level syntax beyond what the schema provides — baseline 3.

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?

States a specific verb and resource ('Add a virtual member to a calendar') and immediately explains the concept — someone without a TimeTree account like a child, pet, or car — which clearly distinguishes it from update_virtual_member and delete_virtual_member siblings.

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?

Explains the context for use (assigning events via virtual_user_attendees) and states the key constraint (max 10 per calendar). It doesn't explicitly route against an alternative, but for a create operation the context is clear enough that an agent knows when to reach for it.

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