stock_screener

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

No annotations are provided, so the description must carry the behavioral disclosure burden. It effectively communicates that this is a read-only screening operation, indicates the 'PRO' requirement, and explains the filtering logic including the '0 = no filter' convention. It doesn't detail rate limits or data freshness, but for a screener these are less critical.

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 a summary line, a detailed args section, and practical examples. It is somewhat verbose due to the number of parameters, but each section earns its place and the information is front-loaded with the core purpose.

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 tool's complexity (9 parameters) and the lack of both annotations and schema-level descriptions, this description is remarkably complete. It covers the stock universe, all filter criteria, the PRO requirement, and provides multiple examples that illustrate realistic usage. An output schema exists, so the absence of return-value documentation is acceptable.

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 0%, but the description fully documents all 9 parameters with meanings, units, examples, and default behaviors. This goes far beyond the bare schema and gives the agent everything needed to set meaningful filter values.

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 opens with 'Screen stocks by multiple financial criteria,' which is a specific verb+resource statement that immediately defines the tool's purpose. It further clarifies the scope by naming Nifty 50 and S&P 500 and listing concrete filter metrics (P/E, ROE, market cap), making it clearly distinct from sibling quote/historical tools.

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 clear context for when to use the tool, with examples like 'Value stocks with high ROE' and 'High dividend yield stocks.' While it doesn't explicitly name alternatives or state when not to use it, the screening focus is evident and the examples serve as practical usage guidance.

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