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

Annotations (readOnlyHint=false, destructiveHint=true) already establish this is a mutating write, and the description does not contradict them. It adds genuinely useful behavioral context beyond the annotations: a video link is auto-included unless in_person is true, and user confirmation is mandatory before invocation. No contradiction detected.

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, front-loaded with the core purpose, and structured with <summary> and <returns> tags. Every sentence earns its place — the confirmation requirement and attendee-lookup routing are operationally necessary, not filler. Slight deduction for the returns clause being thin, though that is more a completeness than a conciseness issue.

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?

Operational context is strong: confirmation protocol, provider ambiguity handling, and attendee lookup are covered. However, there is no output schema, and the returns section only says 'Dict with success status and event details' without specifying keys, error cases, or the shape of the created event — a notable gap for an 8-parameter creation tool with no structured return definition.

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%, so the schema already documents all 8 parameters in detail, including unusually rich guidance on in_person and provider. The description's prose adds only the in_person/video-link linkage, which is a modest supplement; the baseline of 3 is correct since the schema carries the parameter-semantics burden.

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 ('Create a calendar event') with clear scope ('user's connected calendar (Outlook or Google)'). The video-meeting-link behavior further disambiguates it from siblings like update_calendar_event, create_task, and create_todo, so an agent can select it correctly without opening the schema.

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?

Gives an explicit gate for when to call the tool ('ALWAYS present the event details to the user and ask for explicit confirmation before calling') and explicit alternative routing for attendee discovery ('Use search_emails or search_calendar... use find_email'). This is actionable, conditional guidance rather than implied usage.

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