Most famous castles

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

With no annotations, the description carries full burden. It discloses ordering by fame rank and that omitting country gives worldwide results. However, it does not mention that the tool is read-only, nor does it describe any limitations or special behaviors beyond the rank explanation.

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?

The description is two sentences: the first defines the result ordering, the second explains usage and filtering. Every sentence is meaningful and front-loaded with the core purpose.

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?

Given no output schema, the description could benefit from mentioning the return structure (e.g., list of castle names with rank). It adequately covers functionality but lacks completeness on response format.

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?

The input schema covers 67% of parameters with descriptions. The description adds context by explaining the ranking and that category is a filter. It does not introduce new parameter semantics beyond reinforcing the filter concept.

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 clearly states that the tool returns the most famous landmarks worldwide or in a country, ordered by a specific fame rank. It distinguishes itself from siblings like 'search_castles' or 'castles_near' by focusing on ranking based on fame.

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?

The description provides explicit usage guidance: it is the direct answer for 'most famous castles in <country>' and allows filtering by country and/or category. However, it does not explicitly state when not to use this tool or mention alternative tools for different queries.

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