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

The description adds meaningful behavioral context beyond annotations: it discloses that each solve consumes credits ('Cobrado em créditos por solve') and that the output is a submission token. The annotations are all false and do not contradict this, but the description does not mention failure modes, async behavior, or error handling.

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 two short Portuguese sentences with no filler. It front-loads the main action and then gives the essential output and cost information, making it highly concise and well-structured.

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?

With two required parameters and no output schema, the description covers the core purpose and return token, which is helpful. However, it is missing parameter semantics and does not address potential failure/retrieval flows, especially given the existence of captcha_get_result among siblings.

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 has 0% description coverage, and the tool description does not explain website_key or website_url. The parameter names are somewhat self-explanatory for hCaptcha, but the description provides no added meaning and fails to compensate for the low schema coverage.

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 ('Resolve um desafio hCaptcha') and resource (hCaptcha), and also clarifies the output ('Retorna o token pra submeter no site alvo'). This clearly distinguishes it from sibling CAPTCHA-solving tools by naming the exact challenge type.

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 use when an hCaptcha challenge needs to be solved, but it does not explicitly mention alternatives or exclude other CAPTCHA types. With siblings like captcha_solve_recaptcha_v2 and captcha_solve_turnstile, the tool name carries much of the disambiguation burden.

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