index_csindex_all

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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint and destructiveHint=false, so the safety profile is covered. The description adds useful behavioral context beyond that: the return type is a pandas.DataFrame and the data update time is explicitly unknown, which warns the agent about freshness risk.

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 short and front-loads the source and URL before the caveat and return type. Minor redundancy in using both ':return:' and ':rtype:' docstring style, but nothing that gets in the way.

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 parameterless listing call with no output schema, the description covers the source URL, what is returned (latest index list), the return type, and a key caveat about update timing. Enough to call the tool, though the columns returned are unspecified.

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 document. Per the rubric, a parameterless tool gets a baseline of 4.

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 names a specific source (中证指数网站) and resource (指数列表/最新指数的列表), giving a clear verb-less but unambiguous fetch operation. However, it does not differentiate itself from the many sibling index-listing tools (e.g., index_all_cni, index_stock_info, stock_zh_index_spot_em), leaving an agent to guess which list source to pick.

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?

No when-to-use or when-not-to-use guidance is provided. The only note concerns data freshness uncertainty, not selection among alternatives. An agent gets no help deciding between this and the dozens of other index-related siblings.

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