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

Annotations already convey readOnlyHint=true and destructiveHint=false, so safety is covered. The description adds meaningful behavioral context by stating the response 'Contains no creator or contact data' and that the vocabulary is 'currently valid', implying dynamic values. It does not contradict the annotations.

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 English portion is front-loaded and crisp, clearly stating purpose and usage in three sentences. However, the entire description is repeated in German, doubling the length and adding no new semantic information for an English-reading agent. This redundancy prevents a higher score.

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 0-parameter, read-only vocabulary tool, the description covers the returned content categories and the exact conditions for calling it. It lacks a detailed response schema, but given the simple nature of the tool and the absence of an output schema, the description is sufficiently complete for correct invocation.

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 tool has no parameters, so the baseline is 4. The description still adds value by identifying the filter values (city, topics, human_verification_level_min) that the vocabulary informs for search_creators, which helps the agent understand the data's purpose even though this tool itself takes no parameters.

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 a specific verb and resource: 'Returns the currently valid vocabulary for search_creators' and enumerates the content categories (topics, industries, cities, human_verification levels, pricing note). It also differentiates itself from sibling tools by explicitly noting it 'Contains no creator or contact data', which separates it from get_creator and request_outreach.

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 when-to-use guidance: 'Call before a first search_creators request or when unsure about valid filter values (city, topics, human_verification_level_min).' This clearly indicates the condition for invocation. It does not explicitly name alternatives, but as a 0-parameter preparatory tool, alternatives are not necessary and the tie to search_creators is sufficient.

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