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

Annotations already declare readOnly, idempotent, non-destructive, closed-world, so safety is covered. The description adds meaningful behavior beyond that: the reply ends with links that should be rendered as one short line, and the privacy constraint "Public fields only, never a person."

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 correctly with the use case, but the rest is a single dense run-on sentence that bundles return fields, presentation rules, and privacy notes. The link-rendering instruction in particular bloats an otherwise functional definition.

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 usefully enumerates the return shape (event ticket link, whats_on page, company count and links) and the privacy constraint. Enough for an agent to call it correctly; only pagination/limits are unmentioned.

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 0%, so the description must carry the parameters. It labels both explicitly ("city slug", "date YYYY-MM-DD"), matching the schema patterns and giving an agent the expected formats without opening the schema.

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?

Specific verb+resource: events happening in a city on a given date plus whether other travellers are attending. The scope is unambiguous and clearly distinct from list_cities/search_destinations, though the siblings are never named outright.

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?

"Use for any question about what is happening in a city on a date... and whether other travellers are going" gives a clear use condition. It stops short of naming alternatives or stating when-not to use it versus search_public_hooks.

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