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

Annotations already declare the safe read-only profile, so the bar is lower, and the description adds genuine behavioral context: the ranking is by confirmed deals within a specific 24-month window, and output language is controllable. It doesn't describe the shape/count of returned investors, but that is a minor gap.

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?

Front-loads the core question and the ranking rule. The main inefficiency is that the Chinese and English halves largely restate each other, adding length, though the structure remains 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?

No output schema exists, but the description covers the ranking basis, time window, filter semantics, and language control, which is enough for a zero-required-parameter read tool. The only missing piece is a hint about the returned list's size or ordering details beyond 'ranked by deals'.

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 coverage is 100%, so the baseline is 3, but the description adds meaning beyond the schema by clarifying that both sector and tag describe the portfolio companies' attributes rather than the investor's own, and it reinforces the sector-precedence rule. This nuance is not fully spelled out in 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?

States a specific verb+resource: ranks active AI investors by confirmed deal count in the last 24 months, filtered by a sector or topic. The example query ('投资 AI4S 的机构有哪些') makes the intent concrete. It does not name or distinguish itself from the potentially overlapping sibling get_sector_landscape, so it falls just short of a 5.

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?

Provides clear context for when to reach for it ('Which investors back a given sector or topic') plus a worked example. It does not state exclusions or explicitly route the agent to alternative tools for related questions, so no 5.

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