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

Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false; the description goes further by explaining the two-step handoff and that 'Nothing is created until they confirm', which tells the agent the call itself has no side effects. It also adds cost/auth context (free plan, no credit card) that no annotation provides. It does not mention link expiry or whether the same link is reused on repeat calls, which is why it stops short of 5.

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?

Three short sentences, front-loaded with the return value, then the user flow, then the key guarantee. Every sentence contributes new information with no repetition of the schema or annotations.

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 link-generator with an output schema present, the description covers what is returned, what the recipient must do, and that nothing is committed until confirmation. Nothing an agent needs to call or explain the result 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?

With a single parameter at 100% schema description coverage (hostname or URL, with an example), the schema already carries the semantics. The description only adds that the domain is pre-filled in the sign-up flow, which is marginal extra 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?

States a specific verb and resource: 'Return a sign-up link that starts SteadySite monitoring ... for a domain.' The listed deliverables (uptime, SSL expiry, domain expiry alerts, monthly client report) make it clearly distinct from check_ssl_domain_expiry (a diagnostic read) and get_plans (plan listing).

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 sign-up scenario is implied clearly by the described flow (person opens link, signs in, confirms), but the description never states when to choose this over check_ssl_domain_expiry or get_plans, nor any exclusions or prerequisites. Usage is inferable rather than explicit.

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