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

Annotations already declare readOnly/idempotent/non-destructive. The description adds real value beyond them: the scan is header-and-HTML only, single page, and the output is deliberately limited (up to five trackers, three findings). It also flags 'technical findings, not legal advice,' which shapes how results should be presented.

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?

Purpose is front-loaded, and the field enumeration earns its length because there is no output schema. The density is high but every clause carries information; only the field list borders on over-enumeration.

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 no output schema, the description must convey the return shape, and it does so comprehensively: score scale, risk level, cookie/tracker counts, consent platform, Consent Mode, findings, report link. Prerequisite and scope limits are also covered, leaving nothing essential for correct invocation.

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?

Only one parameter, and the schema documents it at 100% coverage ('The preScanId returned by prescan_site'). The description reinforces the origin of the id but adds no syntax or format detail beyond the schema, so baseline 3 applies.

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?

Specific verb ('Return the result') plus resource ('a pre-scan started with prescan_site'), and it enumerates the exact payload so the agent knows what comes back. It is clearly distinguishable from siblings like get_scan_status and get_scan_summary, which serve the full-scan flow.

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?

It establishes the prerequisite (must be a pre-scan started with prescan_site) and draws a boundary against the full scan, which 'requires a CookieInspector account.' It stops short of explicitly saying when to prefer this over the full-scan path in a selection rule, but the context is clear.

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