Screen Stocks

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

With no annotations present, the description carries the full behavioral burden. It discloses several non-obvious behaviors: case-insensitive sector matching, P/E fallback logic, exclusion of untraded instruments, and sorting by turnover. This goes well beyond a simple 'filter stocks' statement.

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?

Two tightly written sentences convey the tool's purpose, filtering criteria, behavioral nuances, exclusions, and sort order without any wasted words. Key information is front-loaded and easy to parse.

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?

The description covers all major behavioral aspects needed to call the tool correctly, especially given that an output schema exists. The only notable gap is the 'limit' parameter, which is not described at all; otherwise, the description is sufficient for a read-only screening 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 description coverage is 0%, so the description must compensate. It adds meaningful semantics: sector is a case-insensitive substring, pe_max uses interim basic P/E falling back to trailing, and price range/volume are explained. However, the 'limit' parameter is not mentioned in the description, leaving that parameter's semantics solely to the schema.

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 a specific verb and resource, 'Filter the live board', and enumerates the exact filtering dimensions. This clearly distinguishes the tool from sibling tools like top_movers or market_summary, which serve different purposes.

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 implies when to use the tool—when you need to screen live stocks by sector, valuation, price, or volume—but it does not explicitly mention alternatives or conditions that would route an agent to a sibling tool. There are no exclusions or when-not-to-use statements.

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