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

Annotations already cover read-only, idempotent, open-world and non-destructive, so the bar is lower. The description adds genuinely new behavioral context: the five result categories (ok, partial, gap, not visible from outside, process control) and the caveat that some controls cannot be verified externally and must be documented by the team — that sets expectations about false negatives.

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 verb and scope, then a coverage list. The list of protocols is dense but each item earns its place by telling the agent what evidence is gathered. No filler or hedging.

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 no output schema, the description carries the burden of describing results, and it does so by enumerating the possible status values. Combined with the stated 16-control scope, an agent knows what it will get back. Only the per-control output shape and cost/runtime are left unspecified.

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?

One parameter with 100% schema description coverage; the schema already explains that a URL is accepted and only the host is used. The description adds nothing about the domain parameter, which is acceptable given the schema does the work — baseline 3.

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: it walks the 16 SEAL DNS & Registrar controls and reports a status per control, with an explicit list of covered areas (DNSSEC, CAA, SPF/DMARC/MTA-STS, locks, expiry, security.txt). It never names or contrasts itself with siblings such as scan_domain or check_registry_lock, despite overlap on locks/expiry, so an agent must infer the difference.

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?

Usage is implied by the certification framing — you run this when you want a SEAL DNS/Registrar readiness verdict rather than raw scan data. There is no explicit 'use this instead of X' routing and no stated prerequisites or exclusions, so the choice between this and scan_domain is left to inference.

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