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

With only openWorldHint in the annotations, the description carries the disclosure burden and does well: it warns that a full baseline scan runs immediately and consumes one of the user's scans. It stops short of stating any ownership/verification requirement or whether monitoring can be removed, but the quota side-effect disclosure is meaningfully beyond the annotations.

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?

Two sentences, front-loaded with the core action, then the side-effect and return-value facts. No filler or repetition of the title.

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?

No output schema exists, so the description correctly closes the loop by naming the return value (scan_id) and the follow-up tool (get_scan_status). Combined with the quota warning, an agent has everything needed to call this correctly and set expectations.

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?

Only one parameter with 100% schema description coverage, so the schema already documents url, its length bounds and format example. The description adds no additional syntax or constraint detail, which is the expected baseline when the schema does the work.

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 ('put a site under continuous monitoring') and enumerates the concrete capabilities: hourly uptime checks, CVE matching, certificate alerts, rescans. It implicitly separates itself from the one-off sibling scan_url via 'continuous', but never names the sibling, so the differentiation is inferable rather than explicit.

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 states a prerequisite ('a site the user owns') and the cost condition ('free for plan holders'), which is useful. However, it gives no explicit guidance on when to choose this over scan_url or monitor_scan_now, so usage context is only implied.

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