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

Goes well beyond the annotations: records who marked it and when, messages nobody, changes nothing else on the event, and repeats calls are no-ops that report `already` (consistent with idempotentHint=true and destructiveHint=false). It also discloses the auth requirement (personal connector token) and the exact refusal code, which annotations cannot convey.

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?

Two dense, front-loaded sentences plus a short return clause; the action and its effect on the open list come first, then prerequisites, side effects, idempotency, authorization and errors. No sentence is filler.

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 supplies the return shape (ok, id, handled, already); with a mutation tool it supplies auth, side-effect boundaries, idempotency and the error case. Nothing needed to invoke it correctly is missing.

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% and the schema already explains both parameters, so the baseline is 3. The description adds only light scoping context — the event must be one the caller hosts and requestId must be a row id from event_guest_requests — without new syntax or format guidance.

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 — marks one guest request handled on a personal event the caller hosts — and names the sibling list tool (event_guest_requests) as the source of the id and the place the request disappears from. An agent can distinguish this from event_guest_requests, event_requests and event_reply without opening a 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?

Explicit about when to use it (marking one request handled, taking it off the hosts' open list) and where the inputs come from (a row of event_guest_requests). It also states the exclusions and failure modes: only hosts may do this, and an id that is not a request on that event is refused with NO_SUCH_REQUEST.

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