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

Annotations already cover the safety profile (readOnly, idempotent, closed-world), so the description's job is to add context, and it does: it discloses the per-call billing cost and enumerates exactly what each row contains (first-mention time, first-mentioning ID and score, source category, re-mention count). It does not discuss ordering, empty results, or rate limits beyond the billing note.

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 concept and its defining window are front-loaded, followed by returned fields, the use case, and the billing note. Slight redundancy: the "此前 7 天没人提" rule appears in both the opening clause and the second sentence.

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?

With no output schema, the description carries the return-value burden and does list the row fields. Missing only minor operational details such as result ordering and behavior when nothing qualifies; sufficient for a read-only discovery tool with fully documented parameters.

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 description coverage is 100%: hours, limit, source, and min_score are all documented in the schema, including the enum values and the score scale. The description only restates "最近 N 小时" and adds no extra meaning, so the baseline of 3 applies.

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 operation on a specific resource with a clearly bounded definition: stocks first mentioned in the last N hours that had zero mentions in the preceding 7 days. That criterion alone separates it from get_market_hot_stocks and get_weighted_hot_stocks, though no sibling is named 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?

It gives an explicit use case — "适合发现新冒头的标的" (good for spotting newly emerging names) — which is clear context for when to pick this tool. It stops short of saying when not to use it or which sibling to use instead for热度 ranking versus first-mention discovery.

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