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

Annotations already declare readOnlyHint, idempotentHint, non-destructive, and a closed world, so the safety profile is fully covered. The description adds genuinely useful return context (the status vocabulary and inclusion of the last check) but says nothing about pagination, result size limits, or what a guest_token requires, which are the remaining behavioral unknowns for a list endpoint.

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 tight sentence with the resource scope front-loaded and no filler. It would be marginally stronger with an explicit verb ('Returns the state...'), but nothing in it is wasted.

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 one-parameter, read-only listing tool with no output schema, the description covers what comes back well enough to interpret results. It is incomplete on the two things an agent must still infer: how to supply guest_token and whether the list is bounded or paginated.

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 0% and the single parameter guest_token is never mentioned in the description, so the agent gets no information about how the token is obtained, whether it is per-user or per-site, or what happens on an invalid token. The parameter name alone has to carry the entire burden.

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 states the specific resource and scope ('every site you monitor') and enumerates the possible states (up, down, waiting, paused) plus the 'last check' field, so the agent knows exactly what this read returns. It is implicitly distinct from singular siblings like check_site or create_site, but it never names or contrasts with them explicitly.

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?

There is no explicit when-to-use or when-not-to-use guidance and no alternative is named. The plural phrasing 'every site you monitor' weakly implies bulk-listing usage, but the agent gets no rule for choosing this over check_site for a single target, matching the MID calibration where an unguided description scored 2.

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