stats

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

The readOnlyHint annotation already declares this is a read-only operation, and the description does not contradict it. The description adds context by listing the specific statistics returned, which is useful for anticipating the output, but it discloses no additional behavioral traits (e.g., rate limits, permissions, or response format). With annotations covering safety, the description provides moderate value beyond them.

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 a single, front-loaded sentence that states the exact purpose and enumerates the key output categories. Every word earns its place, with no verbose filler or redundant phrasing. It is concisely structured and immediately understandable.

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 tool's simplicity (zero parameters, readOnlyHint annotation, no output schema), the description is fully adequate. It lists the five categories of statistics the agent can expect, which compensates for the absence of an output schema. For a stat-fetching tool with no inputs, this is complete.

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 has zero parameters, so the baseline per the rubric is 4. The description doesn't need to document parameter details since none exist, and the schema coverage is trivially 100% with no fields. The description effectively communicates the fixed output scope, compensating for the lack of an output schema.

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 verb ('获取' = get) and resource ('故事库写作统计' = story library writing statistics), and enumerates the specific metric categories (total words, chapter count, series grouping, health, repeated phrases). This clearly distinguishes it from sibling tools like read_chapter or create_story, which serve different purposes.

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 purpose implies when to use this tool (when writing statistics are needed), but there is no explicit guidance on when not to use it or mention of alternative tools. The decision to use it over siblings is left to the agent based on the clearly stated output scope, but no exclusions or alternatives are provided.

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