list_sites

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

No annotations are supplied, so the description carries the full disclosure burden. It does reveal the payload shape (sites plus a capability matrix), but says nothing about whether the call requires authentication, whether results are cached or live, or how large the response can be.

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?

A single sentence with the resource stated first and the purpose trailing it. Every clause earns its place and nothing is padded.

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 tool is simple (no parameters) and an output schema already documents the return values, so the description only needs to convey what is listed and why. That is covered; only auth/prerequisite behavior is left unstated.

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 takes zero parameters, so there is nothing for the description to disambiguate beyond the empty schema. Baseline 4 applies; no parameter gaps exist.

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 states a specific verb and resource — listing registered sites together with their capability matrix — and adds the intent behind it (finding which sites are searchable/downloadable). That is clearly distinct from siblings like search or structured_search, though it does not explicitly name them.

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 clause '用于发现哪些站点已可检索/下载' implies the usage context: check availability before searching or downloading. It stops short of explicit when-not guidance or naming the alternative tools (search, structured_search, download_paper) an agent should call next.

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