open_login

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

Annotations declare the write-ish, open-world, non-idempotent profile, and the description adds real value beyond them: credentials stay on the local machine and cookies are never returned to the model. That privacy/side-effect disclosure is exactly the kind of context annotations cannot express, though nothing is said about what happens on repeated calls or about timeouts.

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 compact sentence with two clauses, front-loading what the tool does before the privacy constraint. No wasted text.

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 behavioral/privacy side is covered and the no-cookie statement partly substitutes for a missing output schema, but the two input parameters are undocumented in both schema and description, leaving the agent without guidance on how to invoke it.

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% and the description says nothing about the 'platform' enum (ctrip/trip) or the 'account' selector. With two undocumented parameters, the description fails to compensate for the coverage gap.

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?

States a specific verb and resource ('打开本地持久浏览器供用户登录'), making clear this launches a login flow rather than checking status. It is distinguishable from the check_login sibling, though it never names or contrasts with it explicitly.

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 purpose implies the usage context (user needs to log in), but there is no explicit when-to-use, when-not-to-use, or pointer to the obvious alternative check_login for verifying an existing session.

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