bilibili_login

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

No annotations are provided, so the description carries the full burden. It only states the output (Base64 image and login_key) but does not disclose behavioral traits such as authentication requirements, rate limits, error handling, or QR code expiration. Minimal behavioral context beyond basic action.

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 consists of two concise sentences. The first sentence states the purpose directly, and the second adds return values and next steps. Every sentence is essential and front-loaded.

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 no output schema, the description adequately explains the return values (Base64 image and login_key) and the next step. However, it omits potential details like QR code expiration time or error scenarios, which would improve completeness for a login tool.

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 input schema has zero parameters, so schema coverage is 100%. The description correctly focuses on the output, as there are no parameters to describe. This meets the baseline of 4 for no-parameter tools.

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 generates a Bilibili login QR code, returns a Base64 image and login_key, and instructs to pass the key to bilibili_login_check. This is specific and distinguishes from sibling tools like search or refresh.

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 implies usage for login by providing follow-up instructions (pass login_key to bilibili_login_check), but does not explicitly state when to use this tool vs alternatives like bilibili_login_check or bilibili_refresh_cookie. No when-not-to-use guidance is given.

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