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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, open-world). The description adds real behavioral detail: it discloses the eight checks returned and flags keyword density stuffing above 3%, which is a concrete threshold not present in any annotation.

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?

One sentence, front-loaded with the core verb and resource, then the element list, then the return characteristics. Every clause carries 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?

For a two-parameter read tool with full schema coverage and annotations, the description is nearly self-sufficient: it names the checks performed and a notable flagging rule. It could still note the URL format tolerance already in the schema, but otherwise there is little an agent needs that is missing.

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 coverage is 100%, so both url and keyword are fully documented with examples. The description adds no syntax, format, or edge-case info beyond what the schema provides. Baseline 3 is appropriate.

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 ('Check'), a specific resource ('how well a page targets one search term'), and enumerates exactly which elements are inspected. This clearly distinguishes it from nearby siblings like check_snippet or scan_page, which do not share this element list.

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 a use case (verifying keyword targeting), but it never states when to choose this over check_snippet, scan_page, or deep_audit. No exclusions or alternatives are named, so routing is left to inference.

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