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

No annotations exist, so the description carries the full burden of disclosing behavior. The description only repeats the title and billing info, giving zero information about side effects (e.g., generating a session token), required prior steps (e.g., obtaining a code via email/SMS), or consequences of failure. It is utterly non-transparent.

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 extremely short, which is concise, but it is under-specified rather than efficiently informative. It wastes the limited text on trivial billing info ('Billing per call: 1 Credits.') while omitting essential operational details. The structure is a single sentence followed by metadata, not front-loaded with actionable information.

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 the tool has 4 parameters, no output schema, no annotations, and no parameter descriptions, the description fails to provide any context. It does not explain authentication flow, required preconditions, return format, or error conditions. For a login-related tool, this is critically incomplete.

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 defines 4 parameters but provides no titles with descriptions, and schema description coverage is 0%. The description does not explain any parameter. 'code' presumably relates to the login code, but 'apiKey', 'proxyUrl', and 'resFormat' are entirely unexplained. The description adds no value beyond the parameter names.

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 title 'login by code' and description 'login by code Group: other. Billing per call: 1 Credits.' provide a basic purpose: this tool logs in using a code. However, it does not specify what the code is (e.g., 2FA code, verification code) or what resource is being accessed, leading to ambiguity. It is not a tautology but lacks specificity and differentiation from sibling tools like get_base_apitools_login or post_base_apitools_loginPost.

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 provides no guidance on when to use this tool versus alternatives such as login or loginPost. It does not explain the context (e.g., after an initial login, requiring a second factor). The 'Group: other' hint is minimal and not actionable. No exclusions or alternatives are mentioned.

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