market_news

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

Annotations indicate read-only and non-destructive. Description adds behavioral details: top 5 results, 7-day lookback, and data source (Finnhub free tier). No contradictions 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?

Extremely concise and well-structured: single sentence intro, then behavior bullet, then Args, then examples. No wasted words.

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?

Covers purpose, behavior, parameter usage, and examples. Output schema exists, so return format further documented. No missing information for an agent to use this tool.

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 provides descriptions for both parameters, so the description's Args line adds little new semantic meaning. However, it clarifies usage in context (e.g., symbol optional, response_format enum values). Baseline 3 due to schema already covering 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 it fetches market news, distinguishing between company-specific and general headlines. It uses specific verbs and resources, and differs from sibling tools like market_quote which provide stock quotes.

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 explains behavior with and without a symbol, including limits (top 5, past 7 days) and examples for common queries. Lacks explicit when-not-to-use or alternatives to siblings, but context and examples suffice.

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