Solve reCAPTCHA

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

Annotations already mark the tool as non-readonly, non-destructive, and open-world. The description adds useful behavioral context: the token is placed in g-recaptcha-response before form submission, guessed sitekeys fail, and v3 scores are immutable. It does not describe potential external service requests or rate limits, but the openWorldHint and schema largely cover the interaction model.

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 three sentences and about 70 words, with no filler or repetition of schema details. It front-loads the main purpose, then packs in the key practical warnings. Every sentence contributes new 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's complexity (9 parameters, nested proxy object, output schema) and the exhaustive input schema, the description covers all essential operational context: what it solves, what it returns, a critical prerequisite, and a fundamental limitation. It does not need to explain return values because an output schema exists, and it complements the rich schema and annotations well.

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 100%, so a baseline of 3 applies. The description adds meaningful parameter guidance beyond the schema by stressing that the sitekey must be read from the page (not guessed) and by noting v3's score cannot be raised, which affects expectations for the version/action parameters. This extra context justifies a score above baseline.

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 opens with a specific verb and resource: 'Solve a Google reCAPTCHA v2 or v3 widget, including invisible and Enterprise variants.' It clearly distinguishes itself from sibling tools (Turnstile, image captcha, Geetest) by naming Google reCAPTCHA and describing what it produces. The returned token's placement in g-recaptcha-response further clarifies its purpose.

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 a concrete prerequisite: 'Read the sitekey from the page first — a guessed sitekey fails.' It also warns about the v3 score limitation, helping agents know not to expect a higher score. It lacks an explicit 'use this instead of X' statement, but the sibling tool names and captcha-specific language make the context clear enough.

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