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

Annotations already cover read-only, idempotent, and non-destructive behavior. The description adds valuable limitations (no bypassing auth/paywalls) and explains the exact return usage ('Returns extracted fields and suggestedBlocks for use with page.create_from_brief'), which goes beyond the structured annotations.

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 efficient and front-loaded: the first sentence states the core operation and outputs. Each subsequent sentence contributes key information (constraints, limitations, integration) without redundancy. Four sentences total, no wasted words.

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 presence of an output schema and annotations, the description provides sufficient context: it explains the tool's position in the workflow (feeds page.create_from_brief), discloses non-obvious limitations, and clarifies the expected return value. No significant gaps remain for an agent to invoke correctly.

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%, with both params (sourceUrl and locale) already documented. The description reinforces sourceUrl's requirement ('public HTTP/HTTPS') but does not add new param-specific details, so it stays at the baseline for schema-complete cases.

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 clearly states the tool's function: 'Fetch a public website URL and extract a structured brief' with specific outputs (business name, description, contact links, suggested blocks). This distinguishes it from siblings like page.create and page.create_from_brief by focusing on the source importing step.

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?

Provides explicit constraints: 'Only works with public HTTP/HTTPS pages' and 'Does not bypass login, CAPTCHA, or paywalls.' It also mentions integration with page.create_from_brief, implying a workflow, though it does not explicitly name alternative tools for other scenarios.

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