fund_scale_change_em

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

The annotations already declare readOnlyHint, idempotentHint, and destructiveHint, so the safety profile is clear. However, the description adds minimal behavioral context—it provides a source URL and return type but does not disclose potential volume, pagination, or coverage details. It neither contradicts the annotations nor meaningfully enriches them.

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 extremely short, but it is under-specified rather than concise. It includes a URL and a docstring-style return annotation, but the primary title line is essentially a restatement of the tool name and adds little value. It is not front-loaded with a purpose statement, so the brevity does not help usability.

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?

With no parameters and no output schema, the description is the only source of information about what the tool returns. It merely provides a URL and '规模变动' (scale changes) with a DataFrame type, but does not describe the data's structure, scope, or any caveats. An agent would not know what rows/columns to expect or how the data is organized.

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 tool has zero parameters, so the schema covers 100% of the parameter space by definition. The description does not need to explain parameters. The baseline score of 4 for zero-parameter tools is appropriate, as no additional semantic guidance is required.

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 is a label-like path '天天基金网-基金数据-规模份额-规模变动' rather than a clear verb+resource statement. It mentions the return type '规模变动' (scale changes) but does not explicitly say the tool fetches or returns this data. It also does not differentiate from sibling fund tools like fund_aum_hist_em or fund_scale_close_sina.

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?

There is no guidance on when to use this tool versus alternative fund data tools. The description lacks any mention of use cases, exclusions, or alternatives, leaving the agent to infer from the name alone. The sibling list is extensive but no comparison is provided.

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