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

Annotations already declare readOnlyHint=true, so the safety profile is covered. With no output schema, the description does real work by enumerating the returned fields (person_id, response, comment, rsvped_on, role_ids), compensating for the missing return contract. It omits pagination, ordering, and empty-result behavior, so it is not fully transparent.

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 tight sentences with the scope constraint and returned fields front-loaded and no filler. The trailing 'Breeze: GET /api/volunteers/list' line is minor redundancy given the breeze_ prefix convention across all siblings, but it is short and 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?

For a single-parameter read with no output schema, the description supplies both the required scoping (one event instance) and the field list, which is most of what an agent needs. Remaining gaps – pagination/limits, whether the instance must belong to a specific event, and empty-result semantics – are minor for a tool this simple.

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?

There is one parameter with 100% schema description coverage ('Numeric Breeze id of the event instance'), which already fully documents format and meaning. The description's 'one event instance' phrasing is consistent but adds no syntax or format detail beyond the schema, so the baseline of 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?

Names a specific resource (volunteers) and narrows scope to 'one event instance', so an agent can distinguish this filtered list from the account-wide list siblings. The verb is only implicit in the name/title rather than stated, and no sibling (e.g., breeze_schedule_volunteer or breeze_get_event) is contrasted.

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 phrase 'scheduled for one event instance' implicitly tells the agent this is a per-instance read and that an instance_id is required. However, there is no explicit when-to-use, when-not-to-use, or pointer to alternatives such as breeze_schedule_volunteer for writes.

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