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

Beyond annotations, the description adds valuable behavioral details: it requires login, is idempotent and returns success even if the product was not followed, and the privacy guarantee that the target user cannot see follow/unfollow actions. These are non-obvious and materially affect agent expectations. No contradiction with 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?

The description is compact, clearly sectioned, and front-loads the signal and trigger condition before the usage chain and caveats. Every sentence contributes distinct information with no filler.

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 one-parameter mutation tool with no output schema, the description covers the trigger, prerequisite data source, idempotency behavior, auth requirement, and privacy implications. Nothing needed for correct invocation is missing.

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 already fully documents the single parameter productId with type and a brief description ('产品 id（cuid）'), so schema coverage is 100%. The description adds that productId can be obtained from get_my_card, which is mildly useful context but not essential, so a baseline 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 action ('本工具取关', unfollow) and the resource (product), aided by the title '取关产品'. It also grounds the use case with a concrete user utterance ('这个不用留着了'), which disambiguates it from sibling tools like unfollow_creator.

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 '【何时用】' section explicitly states when to trigger the tool, and the '【组合链】' gives a practical workflow (get_my_card → unfollow_product). It does not explicitly name alternatives or exclusions, but the product-focused wording and sibling set make the target scenario clear enough.

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