Taobao Item Card

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

Annotations already mark it read-only and non-destructive. The description adds meaningful behavior beyond that: price_cny may be None on hidden/variant pricing and is never 0, and it enumerates specific error types including login-wall/CDP failures and parser drift. This gives an agent realistic expectations.

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 compact and well-structured: purpose sentence first, then Return Format and Error Format sections. Every sentence carries information, with no filler or repetition.

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 one-parameter, read-only card fetch with an output schema, the description covers purpose, return contract, price edge case, and failure modes. An agent has everything needed to call it correctly and interpret the result.

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%, and the schema already documents item_id_or_url as 'Item id or item.taobao.com URL'. The description adds no further parameter-level detail, 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 opens with a specific verb and resource: 'Fetch one Taobao item card.' It clearly distinguishes this from sibling tools like taobao_search and taobao_selfcheck by signaling a single item-card retrieval rather than a search or health check.

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 phrase 'Fetch one' plus the item_id_or_url parameter makes the direct-lookup use case clear. It does not explicitly name alternatives or state when not to use it, but the context is strong enough that an agent can select it appropriately.

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