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

Annotations are not provided, so the description carries the full burden. It implies a read-only operation via '查看' (view) and places it 'before fetching data', which adequately communicates non-destructive behavior for a describe tool. However, it does not explicitly mention additional behavioral details like return format or potential errors, and there is no annotation context to supplement.

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, well-structured sentence in Chinese. It front-loads the core purpose and then adds usage context, with no redundant words or filler. It earns a perfect score for conciseness.

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 and no annotations, the description should clarify what the agent receives as a response. It states the tool shows '完整欄位定義' (complete field definitions), which is a reasonable hint, but it does not specify the format or structure of the returned definitions. For a simple describe operation with one fully documented parameter, this is an adequate but not rich description, so a 3 is justified.

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 schema has 100% coverage for the one parameter, dataset_id, with a helpful description (e.g., '來自 twse_search_datasets 的資料集代號'). The tool description itself does not add parameter-level detail beyond what the schema provides, so the 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 the tool's function: '查看某個資料集的完整欄位定義' (view the complete field definitions of a dataset). It uses a specific verb (view) and resource (field definitions), and the context '取資料前' (before fetching data) distinguishes it from the sibling tool twse_get_dataset that likely fetches data.

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 usage context: '取資料前用來確認要過濾／投影哪些欄位' (before fetching data, use it to confirm which fields to filter/project). It implies using this tool before twse_get_dataset, but does not explicitly name alternatives or state when not to use it, so it falls just short of a 5.

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