Create a calendar event

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

Beyond the annotations, the description discloses critical behavioral details: the side effect of immediately sending invitations to attendees, the return of the created event, and the timezone interpretation for naive start/end values. This is exactly the kind of context an agent needs for a mutating tool.

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 sentences, each earning its place: purpose/return, side-effect warning, and timezone behavior. The most important operational warning is front-loaded after the purpose, and there is no redundant or filler text.

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 10-parameter mutation tool with no output schema and minimal annotations, the description covers the non-obvious essentials: target calendar, return value, immediate invitation side effect, and ambiguous timezone handling. The remaining parameter details are already fully documented in the schema.

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 baseline is 3. The description adds one meaningful clarification beyond the schema: when timeZone is omitted, naive times default to UTC. It does not repeat parameter docs, which is appropriate.

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 states a specific verb and resource: 'Creates an event on the primary calendar' and adds that it returns the created event. This clearly distinguishes it from update, delete, respond, and list tools in the sibling set.

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 gives clear context for when to use the tool: creating a new calendar event on the primary calendar. It also provides explicit pre-call guidance by warning that attendees will receive invitations immediately and telling the agent to confirm details first. It does not explicitly name alternatives, but the usage context is clear.

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