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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=true, so safety is covered. The description adds genuine value beyond them: the required auth (user's Cotlet API key with access to this app) and the scoping that only events the user owns are returned.

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?

It is front-loaded with the purpose and return fields, and every sentence is short. The RSVP-invitation constraint is slightly tangential to listing events but still supplies relevant context, so only minor trimming is possible.

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?

With no output schema and an empty input schema, the description carries the burden and does return the key returned fields plus the auth prerequisite. It does not mention ordering or completeness of the list, which would fully round it out.

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 tool takes zero parameters, so there is nothing for the schema to document and no param meaning to add; baseline for 0 params is 4. The description appropriately introduces no arguments.

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 gives a specific verb (list) and resource (wedding events) and names the data returned (type, name, date, start time). It scopes the source precisely to the events in "Your Events" and enumerates typical entries (ceremony, reception, rehearsal dinner), so an agent can distinguish it from RSVP/tracking 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?

It explains a downstream use ("Use event_id from each item in the RSVP and invite tools") and a guest constraint, which implies context. However it never states when to call this versus alternatives like zola_track_rsvps or the invite tools, so usage remains implied rather than explicit.

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