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

No annotations are provided, so the description carries the full burden. It does disclose a real behavioral trait: a commonly expected field (participation count) is deliberately omitted for cost reasons, which prevents an agent from wasting calls hunting for it. However, it says nothing about read-only semantics, permissions, or result characteristics beyond what the schema already covers.

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 packed sentences: purpose and scope first, then the exclusion and the redirect. The parenthetical giving record count and the cost rationale are informative rather than filler. Slightly dense but nothing wasted.

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 search tool with no output schema, the description covers purpose, scope, a notable data limitation, and the sibling alternative. Pagination and field selection are fully handled by the schema, so no gaps an agent would trip on remain, though return-shape context is absent.

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 100%, so the schema already documents all five parameters including the limit cap and offset bounds. The description's mention of dimensions (类型、总部、关注阶段、关注赛道) loosely maps to the fields/focus_stage params but adds no syntax or format detail beyond what the schema provides, so the baseline of 3 applies.

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?

States a specific verb (检索) and resource (投资机构 / fa_investor), gives the dataset size (2.5万家) and enumerates the dimensions covered (类型、总部、关注阶段、关注赛道). Crucially it distinguishes itself from the sibling search_investments by declaring what it does NOT return, so an agent can choose between the two without opening schemas.

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?

Explicitly gives a when-not condition (参投次数 is not provided, because counting the whole table by institution name is cost-prohibitive) and names the alternative (use search_investments' investor parameter to query by event). This is concrete routing guidance, though it only addresses that one case rather than the broader when-to-use context.

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