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

readOnlyHint=true already establishes the safety profile, so the bar is lower. The description adds the aggregation model (time-bucketed counts of attendees and orders) which is beyond annotations, but omits response shape, pagination, and auth requirements.

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 compact sentences, front-loaded with the resource and result content; the API endpoint is tucked at the end. No waste, though the endpoint reference is marginal value for an agent.

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 an 8-parameter aggregation tool with no output schema, the description should clarify the report's structure and its distinction from get_sales_report. Annotations cover safety and the schema covers params, but sibling differentiation 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 description coverage is 100% (every param documented, including the tricky date_facet/period interaction and timezone default). Description adds nothing beyond that, so baseline 3 is appropriate.

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+resource ('Attendee report for one or more events') with detail on the content ('number of attendees and orders per time bucket'). However it does not differentiate from the sibling 'eventbrite_get_sales_report', which is a closely related report tool — an agent cannot easily tell which report to choose.

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?

No when-to-use guidance, no alternatives named, and no exclusions. The closest sibling (get_sales_report) is never addressed, so the agent has no routing signal.

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