U-App get yesterday data

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

No annotations are provided, so the description carries full burden. It only states it gets 'yesterday statistics' with no details on what metrics are returned, permissions needed, or side effects. This is insufficient for understanding the tool's behavior.

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 very short (one sentence) and to the point, but it lacks crucial details. Still, it is not verbose, so it earns a high score for conciseness, though it could be improved by adding more structure.

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?

Given the lack of output schema, annotations, and the presence of many similar sibling tools, the description is incomplete. It does not specify what 'yesterday statistics' includes, nor does it provide any context about prerequisites or limitations.

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% (the only parameter appkey is described as 'Umeng appkey. If omitted, UMENG_DEFAULT_APPKEY will be used.'). The description adds no additional meaning beyond the schema, so a baseline of 3 is appropriate.

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 clearly states 'Get yesterday statistics for an app.' It specifies the verb 'Get' and the resource 'yesterday statistics for an app,' and it naturally distinguishes from siblings like umeng_uapp_get_today_data (today's data) and umeng_uapp_get_today_yesterday_data (both).

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 guidance is provided on when to use this tool versus alternatives. The sibling list includes many similar tools (e.g., get_daily_data, get_today_data, get_today_yesterday_data), but the description does not help the agent choose among them.

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