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

Annotations only declare readOnlyHint and openWorldHint, so the description carries and delivers the real substance: 503 on challenge/transport failure, a 200-with-low_confidence=true edge case that must be checked, and pre-IO rejection of site: queries. These are non-obvious failure and trust signals an agent needs.

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?

Six tight sentences, each carrying distinct information, with the tool's identity front-loaded and the sibling-routing guidance placed at the end. No filler or redundancy.

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 an output schema present, return-value shape needn't be described, and the description instead covers the failure modes, the low-confidence signal, locale defaults, and alternatives. That is everything an agent needs to call it correctly.

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 description coverage is 100%, so all five parameters (including Count clamping, Page, Country, Language) are already documented. The description only restates the locale defaults already in the schema, adding no meaning beyond structured fields, so the baseline 3 applies.

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 (Search) and resource (public Bing web results) plus scope: organic rows, optional context modules, and page pagination. It explicitly differentiates itself from siblings by naming brave_search and bing_news, so an agent can route correctly without opening schemas.

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?

Provides explicit alternatives and the conditions that select them: 'Use brave_search for domain-restricted searches or bing_news for news results', and notes that site: queries are rejected. This covers both when-to-use and when-not-to-use with concrete triggers.

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