douyin_check_login

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

Annotations already declare readOnlyHint=true, and the description reinforces this with '只读' (read-only). It adds the behavioral detail of opening a local Chrome profile directory, but does not clarify any potential side effects (e.g., launching a browser) or what the status outcome looks like. Since annotations cover safety, the added context gives a moderate score.

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, compact sentence with no filler. It front-loads the key action and scope, making it highly concise and easy to parse.

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?

The tool is simple with no parameters and annotations clarifying read-only intent, but the description does not disclose what the tool returns (no output schema) or whether opening the directory has side effects. For a login-check tool, the agent would benefit from knowing the result format, so completeness is moderate.

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?

There are zero parameters, so the schema provides no parameter details. The description need not explain any parameters, and with an empty schema, the baseline of 4 applies based on the rules.

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 action: opening the local dedicated Chrome profile directory and checking the Douyin login or verification code status. This clearly distinguishes it from sibling tools like douyin_search_videos or douyin_close_browser, which handle other concerns.

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 the tool is used to verify login state, which is a clear context, but it does not explicitly state when to use it vs alternatives, nor mention any prerequisites or exclusions. The guidance is present but underdeveloped.

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