key_ratios

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

With no annotations provided, the description carries full burden. It transparently lists categories of metrics returned and the geographic scope (Indian and US stocks). However, it omits potential limitations such as data lag, error handling for invalid symbols, or any destructive effects. The tool is clearly a read operation, but no explicit statement on that is given.

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 well-structured with bullet categories and concrete examples. It is moderately concise but could be slightly tightened without losing clarity. The front-loading of the purpose is good, and each section adds value.

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 presence of an output schema (not shown here but context indicates it exists), the description need not detail return values. It covers the single parameter adequately with examples and specifies geographic coverage. It does not address potential edge cases or data freshness, but overall it is sufficiently complete for a ratio retrieval 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?

The single parameter 'symbol' has zero schema description coverage (only a title in schema). The description compensates fully by providing examples (e.g., RELIANCE, AAPL, HDFCBANK) and explaining it is a stock ticker. This adds crucial meaning beyond the schema stub.

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 begins with a clear verb+resource statement: 'Get key financial ratios and valuation metrics for a company.' It further details categories like Valuation, Profitability, Growth, etc., making it distinct from sibling tools such as balance_sheet or income_statement which focus on specific statements rather than derived ratios.

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 examples of usage (e.g., for RELIANCE, AAPL) and mentions it works for Indian and US stocks, implying broad applicability. However, it does not explicitly state when to prefer this tool over siblings like balance_sheet or income_statement, nor does it mention when not to use it.

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