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

Annotations already declare readOnlyHint, idempotentHint and openWorldHint=false, so the safety profile is covered. The description usefully adds ordering (newest first) and the shape of each returned item (status, public link), but says nothing about pagination or how the default of 20 relates to the cap of 50.

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?

A single well-formed sentence with zero filler; scope, ordering and returned fields are all front-loaded.

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?

The output schema exists, so return values are already documented, and annotations cover the safety profile. The gap is the undocumented limit parameter and the absence of any pagination context, which matters for a listing tool.

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?

There is one parameter (limit) at 0% schema description coverage, and the description never mentions it, its default of 20, or the maximum of 50. The schema carries type and bounds but the description adds no meaning, leaving the agent to infer the parameter's behavior entirely.

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?

Names a specific verb (Lists) and resource (websites) plus the scope (signed-in person) and ordering (newest first), so the agent can distinguish it from get_site or create_site. It stops short of explicitly stating the list-vs-single-item distinction, relying on the reader to infer it from the verb.

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 the read scenario (enumerating the signed-in user's sites) but never says when to reach for this versus get_site or when it is not appropriate. No alternatives or exclusions are named.

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