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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the 'Read-only. No money.' line adds little. The genuinely additive context is '(needs account token)' and the description of the ribbon's contents, which stands in for a missing output schema. The three trailing sentences about never buying things repeat a policy rather than disclose tool behavior.

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 core sentence and the parameter modes are front-loaded and efficient, but three near-identical sentences about not buying domains, emails, or subscriptions without asking are irrelevant to this read-only tool and pad the description substantially.

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-optional-parameter read tool with no output schema, the description covers auth requirements, the three usage modes, and what the returned ribbon contains. It is largely complete; the main detraction is the off-topic purchasing boilerplate rather than missing information.

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 the baseline is 3, but the description goes beyond the schema by explaining the mutually exclusive modes (site_id vs host vs omit both to list), which the schema does not express. That is real added meaning.

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 a specific verb and resource: it returns an embed line for a Site of the day award plus paste instructions, and it names what the ribbon contains. It is clear on its own, but it does not distinguish itself from named siblings such as award_readiness or choose_link.

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 gives explicit selection rules: pass site_id for a site on this account, host for any confirmed winner, or omit both to list earned awards. This is a complete set of when-to-use branches with no inference required.

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