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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and closed-world, so the safety profile is fully covered. The description adds real context beyond that: it discloses the per-mode return shape ('full details', 'groups, ticket types, and additional fields') and the cross-tool dependency on search_events for a valid event UUID. It stops short of stating pagination limits or result caps.

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?

Front-loaded one-line purpose followed by a compact bulleted dispatch table and a single constraint sentence. No filler; each clause maps to a distinct action or prerequisite.

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 a rich oneOf schema, full description coverage, an output schema, and strong annotations, the description supplies everything needed to select a mode and supply required identifiers. Only list-mode behavior at scale (pagination defaults, result limits, filter interaction) is left implicit.

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 oneOf already encodes which fields each action requires, so the schema does much of the work. The description still adds value because the `action` enum values carry no per-value descriptions in the schema — the bullets give each action meaning and tie `user_id` to the `get` mode specifically.

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 ('Read attendees') scoped to a single event, then decomposes the tool into three named modes (list/get/metadata) so an agent can tell exactly which capability it is selecting. This cleanly separates it from siblings like read_registration or update_attendee.

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?

Each action is annotated with its purpose and the prerequisites needed ('get' Requires `user_id`; 'metadata' is for building list filters), and the description names search_events as the source of the required event_id. There is no explicit statement of when not to use it (e.g., to modify an attendee, use update_attendee), but the mode-level guidance is clear.

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