子账号流量

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

Annotations already establish the safe read-only, idempotent nature. The description usefully adds behavioral constraints beyond annotations: results are daily, in MB, interval max 30 days, and end date must not be later than today. This is valuable operational context without contradicting annotations.

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?

Two concise, front-loaded sentences cover the action, resource, key output unit, and the two most important constraints. Every phrase earns its place with no repetition of schema details.

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 simple read-only query with fully documented parameters, the description is nearly complete: it states daily granularity, units, and date constraints. The only minor gap is not detailing the exact response shape, but with no output schema this is acceptable given the clear daily-flow summary.

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 each parameter is already documented. The description adds a cross-parameter constraint not present in the schema—the 30-day maximum interval—and clarifies output units, which helps an agent construct valid date ranges.

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 clear action ('查询'), the exact resource (动态住宅子账号的每日流量), and a meaningful output detail (flow 单位 MB). This distinguishes it from sibling tools like main_account_flow and bandwidth_trend by explicitly scoping to a sub-account.

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 description gives clear context: it is for querying a specific sub-account's daily traffic in a date range. It does not explicitly name alternatives or say when not to use this tool, but the sub-account versus main-account focus provides enough practical guidance for selection.

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