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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and non-destructive. The description adds beyond this by mentioning the data source (DuckDuckGo Instant Answer API) and that no auth is required. It also clarifies output shape with 'flattened list', which is useful. No contradiction with 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?

Three sentences, each earning its place: the first defines the action and result, the second gives usage context, the third specifies the data source and auth. No fluff, no repetition.

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 simple one-parameter read-only tool with an output schema and full annotation coverage, the description covers purpose, use cases, data source, and auth requirements. Nothing an agent needs to invoke it correctly is missing.

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 covers the single 'query' parameter 100%, so the baseline is 3. The description adds only marginal value via examples ('Python programming language', 'coffee') and explains the query is meant to retrieve related topics, but it doesn't add specific details like encoding, length limits, or formatting beyond what the schema already states.

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?

States a specific verb ('Get') with a clear resource ('DuckDuckGo related/disambiguation topics') and describes the output format (flattened list of related concepts, categories, or alternate meanings, each with a title and link). This clearly differentiates it from the sibling duckduckgo.search.instant_answer, which would return a single instant answer rather than a list.

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?

Explicitly says it is 'useful for exploring ambiguous or broad queries' and gives concrete examples (a name mapping to multiple people, a category like 'coffee'). This gives clear context for when to use the tool, though it does not explicitly name an alternative or state when not to use it.

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