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

Annotations already cover the safety profile (readOnlyHint=false, destructiveHint=false, idempotentHint=false), and the description adds real context beyond them: subject to plan limits, creates a manual mobile site, and returns a siteId consumed by run_audit. Removal being app-only is also useful, though rate/duplicate behavior is unstated.

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 with zero filler: purpose and return value first, constraint and alternative after. Every sentence earns its place and nothing is buried.

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 an output schema present, the description needn't explain return shape, and it still flags the siteId handoff to run_audit. Combined with the plan-limit caveat and the alternative tool, an agent has everything needed to invoke it correctly.

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 100%, so url and name are already documented with formats, bounds, and the hostname default. The description only references the url indirectly ('public site') and adds no syntax or naming behavior beyond the schema, so the 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?

States a specific verb and resource ('Save a public site for repeat checks') plus the concrete outcome (returns siteId for run_audit). It also differentiates itself from the one-off sibling audit_url by name, so an agent can route correctly without opening either schema.

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?

Gives explicit conditions: use this for repeat checks, use audit_url for a one-off check, and remove saved sites in the Nimo app rather than via a tool. It lacks guidance on duplicate handling, which matters given idempotentHint=false, but otherwise the when/when-not routing is clear.

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