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

Annotations already declare readOnly, idempotent, non-destructive, closed-world, so the safety profile is covered. The description adds return content (name, description, coordinates, visit minutes, page URL), which is valuable given no output schema; it does not mention rates, limits, or defaults, so not a 5.

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?

Three tight sentences: capability and scope first, concrete examples second, return shape last. Each sentence earns its place; only the example sentence is slightly tangential but it is high-value for intent matching.

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 15-parameter search tool with no output schema, the description supplies both the filter catalogue and the return fields. Minor gaps (no mention of pagination via limit, sorting semantics, or language switching) keep it from a 5, but the schema covers those adequately.

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 60%, so the structured field already documents most parameters. The description meaningfully maps filter dimensions to intent ('category, interests, historical period, indoor/outdoor, visit length, free entry or distance from a point'), covering most of the 15; sort, limit, country, and language are left entirely to 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?

The description uses a specific verb ('Search') and resource ('individual sights'), plus the scope ('all cities or within one city'). It enumerates the filter dimensions rather than restating the name, but does not explicitly distinguish it from siblings like recommend_attractions (interest-based) or find_nearby_attractions (distance), which overlap with 'distance from a point'.

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-case context is clear: 'five Byzantine sights in Istanbul, Gothic churches in Spain, or free things to do in Rome' shows exactly when to reach for it. No when-not invocations or alternative tools are named, however, so the agent must infer the boundaries against recommend_attractions and find_nearby_attractions.

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