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

The description details the internal execution process (runs HackerNews + Wikipedia + DuckDuckGo simultaneously, then Groq distills), the output format (single confident reply with source attribution), and requirements (API key, cost). While annotations declare readOnlyHint on openWorldHint, the description adds specific behavioral and operational context that annotations do not provide, making it highly transparent.

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 that are information-dense with no fluff. It front-loads the primary functionality, immediately follows with usage guidance, and rounds out with cost and auth requirements. Every sentence earns its place.

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 the moderate complexity (multi-source search with synthesis), the description fully explains the tool's purpose, sources, output style, cost, and prerequisites. No output schema exists, but the description describes the output as an 'authoritative answer with cited sources,' which is sufficient for an agent to understand the return value.

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 schema coverage is 100% with a single 'query' parameter that includes a description and example. The description adds no additional parameter-specific details beyond the schema, so the baseline of 3 applies. The description does suggest the query should be specific, but this is already in the schema via the parameter description.

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 action: '3-parallel-source search + Groq synthesis → one authoritative answer with cited sources.' It explicitly differentiates from the sibling tool 'web_search' by saying 'Use instead of web_search when you need a definitive answer, not just links,' which identifies the unique value proposition.

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: 'Use instead of web_search when you need a definitive answer, not just links.' It also mentions cost ($0.05) and the API key requirement, which are important usage conditions. This goes beyond vague hints and gives clear context.

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