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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the description doesn't need to restate those. It adds context about the tool's scope (US stocks) and the summary nature of the data, but doesn't disclose potential edge behaviors such as handling of invalid tickers or rate limits. With annotations covering the safety profile, this is adequate.

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 succinct and well-structured: a one-sentence function summary, a clear pointer to an alternative tool, and a formatted Args block. No redundant text; 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?

This is a simple single-parameter read-only tool with an output schema present. The description covers the purpose, the nature of the returned information, and the key alternative. Since the output schema exists, detailed return format documentation is not necessary.

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 only defines ticker as a required string with no description. The description compensates by explaining 'The ticker symbol of the stock to get information for' and providing an example ('AAPL'), giving the parameter clear meaning beyond the schema's raw type.

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?

Clearly states the tool's function: 'Get a summary of key information for a given ticker symbol' and enumerates specific data categories (price, market cap, ratios, dividend, etc.). It also explicitly contrasts with get_financial_statement for detailed statements, distinguishing its scope.

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 an explicit recommendation to use get_financial_statement when detailed financial statements are needed. While it doesn't mention other sibling tools like get_finance_news or get_market_overview, the core use case and one key alternative are clearly stated.

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