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

Annotations already declare readOnlyHint=true, openWorldHint=true and destructiveHint=false, yet the description adds real behavioral value: the payload contains personal data (e-mail addresses, RSVP form answers), the max page size is 20, and IP addresses and coordinates are stripped from the reply. Rate limits and permission requirements are not mentioned, keeping it short of a 5.

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?

Four dense sentences that are front-loaded with the resource and privacy note, and each sentence carries information (scope, filters, paging, data redaction). The trailing "GET /rsvps." is near-redundant but harmless.

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, the description carries the burden of describing the return, and it does so adequately: the fields of interest (emails, form answers), the redaction of IP/coordinates, and the paged 20-per-page shape. Only omission is the default page size and the empty-filter behavior, both partly covered by 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 description coverage is 86%, so the schema already documents paging, sorting, and the id arrays. The description only restates the filterable dimensions (calendar, event, response going/maybe/not-going) without adding syntax, defaults, or interaction rules beyond what the schema provides; baseline 3 applies.

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+resource ("List RSVP attendees") and immediately scopes it with the data returned and the supported filters. It is clearly distinguishable in practice from addevent_get_rsvp_attendee (singular) and addevent_create_rsvp_attendee, but it never explicitly routes the agent away from those 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?

"Filter by calendar, event or response" plus "read only what the task needs" implies when and how narrowly to call it, but this is guidance about parameters rather than tool selection. No alternative tool is named and no when-not-to-use condition is stated.

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