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

Annotations already declare readOnlyHint and openWorldHint, so the safety bar is low; the description still adds real value by disclosing the data source (public Brave Search news HTML) and a concrete failure mode (503 on challenge pages or unusable HTML). It stops short of retry/rate-limit guidance, so it is strong but not exhaustive.

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 provenance and 503 disclosure are front-loaded and earn their place, but 'Query: Search query. Required, e.g. openai. Count: Results to return, default 10, clamped to 1..50.' duplicates schema text word-for-word, and the final sentence is a terse fragment. Appropriate length overall with some wasted sentences.

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?

An output schema exists, so return values need not be explained, and annotations cover the read-only/open-world profile. The description adds locale defaults, source, and the 503 failure mode, leaving an agent well-equipped to call it, with only retry behavior and date-filter interaction for custom time ranges unaddressed.

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 the schema already documents all 8 parameters, including enums for Country, Language and TimeRange. The description merely repeats the Query and Count semantics verbatim and adds nothing about date/time parameters, so 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 and resource ('Returns normalized Brave news search results for a query string') and names the sibling brave_search, so an agent can distinguish it from the general web search tool without opening the schema. The word 'news' plus 'normalized' makes the scope precise.

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?

Names the alternative sibling ('Use brave_search to search Brave'), implying news-specific queries belong here and general web queries elsewhere, but it never states when NOT to use this tool or when the alternative is preferred beyond the news/general split. Clear context, no explicit exclusions.

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