i_login

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

With no annotations, the description carries the full burden and does substantial work: it discloses that the server is short-lived ('serves it for a few seconds, then shuts itself down'), pre-empts a confusing failure ('a later "connection refused" on that tab is normal'), and states that cookies are captured automatically. It does not mention failure modes such as port conflicts or the case where no browser is available.

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?

Front-loaded with the action and the returned URL, then proceeds stepwise through the user flow and the follow-up call. It is slightly long and the parenthetical about the shutdown is wordy, but every sentence supplies information an agent needs to sequence the flow correctly.

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?

There is no output schema, and the description supplies the return value (the URL), the human-in-the-loop procedure, the expected post-login page state, and the required follow-up tool calls. For a one-optional-parameter tool this covers everything an agent needs to invoke and complete the flow.

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 single optional 'port' parameter is fully documented in the schema (100% coverage, default 7788), so the schema already does the work. The description never mentions the port or when a caller would override it, so it adds no meaning beyond the schema; baseline 3 applies.

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 ('Start a local reverse-proxy login server for iconfont.cn') plus the return value ('return its URL'). It is clearly distinguishable from the sibling login variants (i_login_with_password, i_login_with_cookie, i_login_with_sms) because it is a browser-driven flow, and it explicitly labels itself the recommended method.

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?

Gives a clear when-to-use signal ('This is the recommended login method') and an explicit next step ('Then call i_login_wait (or i_check_auth) to confirm'). What is missing is an explicit exclusion, e.g. when a headless or credential-based sibling such as i_login_with_password should be chosen instead, which the 'open in your normal browser' requirement only implies.

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