sites_index

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

With no annotations, the description carries the burden and does disclose the observable behavior that matters for a zero-parameter tool: it returns the complete set of indexed sites and names the four fields returned. It stops short of stating whether the result is cached, permission-gated, or paginated.

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?

One short sentence, front-loaded with the action and scope, with the field list compactly attached. Nothing is redundant or 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?

For a trivial no-argument listing tool with no output schema, the description covers both what is returned and which fields each entry carries. Only the relation to sibling tools (site_detail, site_content, site_search) is left for the agent to infer.

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 no parameters, so the baseline is 4. The parenthetical field list adds useful information about the shape of each result row, which is not present in the schema since there is no output 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?

Specific verb+resource: "取全部已接入站点索引" (get the index of all connected sites) with the returned fields enumerated (key / name / group / URL). It is clearly separable from siblings like site_detail or site_content by the word "index" and "全部", though it never names those siblings explicitly.

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?

Usage is only implied: the "all sites" framing suggests a discovery/listing step before site_detail or site_content, but the description never states when to call this instead of site_search or site_detail. No prerequisites or exclusions are given.

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