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

Annotations already declare readOnly, idempotent, non-destructive and closed-world behavior, so safety is covered. The description adds genuinely new behavioral detail: result ordering ('soonest first, or nearest first when near_lat/near_lng are given') and the default limit, which the annotations cannot express.

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 sentences, zero waste: the purpose and facets lead, then the return contract and ordering rules follow. Every clause carries information the agent needs, and nothing is padded.

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 14 all-optional parameters and no output schema, the description usefully enumerates the returned fields (dates, status, place, type, size, description, website, atlas page) and the ordering rule. It omits empty-result behavior and any pagination caveat, which is a minor gap for a search tool.

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%, so baseline is 3. The description goes slightly beyond the schema by clarifying the interaction between sort defaults and the near_lat/near_lng pair, and by naming limit as a control on result count, which is more than a restatement of field docs.

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 and resource ('Find visual-art spectacles worldwide') plus the facet set (trip dates, place, type, size), so the agent knows exactly what it retrieves. It does not differentiate from siblings get_event or list_filters, which caps it below 5.

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?

Usage is only implied through the facet list ('by trip dates, place, type and size'), which hints at trip-planning scenarios. There is no explicit when-to-use, no when-not, and no mention of get_event as the follow-up for a single result, so the agent must infer the routing.

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