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

With no annotations provided, the description carries the full burden and does: it discloses reverse-chronological ordering, that pagination only walks backwards with no date filter, that index step equals the prior limit, the 200-item cap, and a 1-minute cache that dedupes repeated calls. These are exactly the operational traits an agent needs.

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 resource and its ordering, then routes to the sibling, then gives paging/limit/cache warnings. Dense with bold and emoji markers, and slightly longer than strictly necessary, but every sentence carries distinct operational content.

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 two-param feed tool with an output schema, this is complete: it covers scope, triggers, sibling routing, pagination mechanics, limits, and caching. Nothing needed to call it correctly is missing.

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 baseline is 3, but the description goes beyond the schema by giving the pagination formula (step = last limit, e.g. limit=20&index=20 for page two) and reiterating the 200 cap, which the schema states only as a default/upper bound.

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 resource (7×24 财经快讯 / 全市场电报), ordering (按时间倒序), typical sources, and enumerates the row fields. It explicitly distinguishes itself from ashare_news by scope (whole-market vs per-stock), so an agent can pick it 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?

Gives concrete user-intent triggers ('今天有什么大消息/最新财经新闻/刚才发生了什么/宏观突发事件') and an explicit division of labor with ashare_news — market/macro/breaking here, single-stock news there. Both when-to-use and when-not-to-use are covered.

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