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

Annotations already declare readOnlyHint=true, so the description correctly implies a safe read operation. It adds context about the data source (Eastmoney) and explains parameters, but does not detail rate limits or pagination beyond the limit parameter. No contradiction.

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 concise and front-loaded with the main purpose, followed by a clear list of arguments. Every sentence is necessary, 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?

For a simple screening tool with three parameters, the description covers the inputs well. However, it does not describe return values or pagination behavior, which could be inferred but is not explicit. Given no output schema and the openWorldHint, slightly more detail would improve completeness.

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 bears full burden. It explains all three parameters: sector (optional with examples), market_cap_min (CNY), and limit (max rows, default 50). This adds significant meaning beyond the schema's type/default definitions.

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 the tool screens Mainland China A-shares via Eastmoney data, distinguishing it from sibling tools targeting other markets. The verb 'screen' combined with market specification and data source provides specific and unambiguous purpose.

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 does not explicitly state when to use this tool versus alternatives, but the sibling tool names and the tool's name make it clear that it is for China A-shares. No guidance on when not to use or what prerequisites exist.

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