check_login

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

Annotations already cover read-only, idempotent, non-destructive and open-world traits, yet the description adds real value beyond them: it warns that a null result means the state cannot be confirmed and that the presence of a Cookie does not prove a login. That failure-mode nuance is exactly what an agent needs before trusting a result.

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?

A single dense sentence: purpose first, then the return-value caveat. Every clause earns its place and nothing is padded, though the compressed phrasing makes the subject of the check slightly ambiguous.

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 two-parameter, read-only tool with no output schema, the description covers purpose and the key result caveat, but leaves parameter semantics entirely unaddressed and never positions itself against open_login. Adequate but visibly short of complete.

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 description coverage is 0%, so the description carries the full burden for 'platform' (required enum ctrip/trip) and 'account' (default, pattern), but neither parameter is explained or mapped to meaning. Only the vague phrase '网页登录标识' gestures at the inputs.

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 names a specific verb (核对/verify) and resource (登录状态, via a web login identifier), and clarifies the result semantics (null means unconfirmed). It does not name the sibling open_login to contrast itself against, so it stops short of a 5.

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?

There is no statement of when to call this versus alternatives; the obvious sibling open_login is never mentioned, nor are prerequisites or sequencing (check before a session-dependent action). Usage is only implied by the verb.

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