Domain Intel

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

Annotations already declare readOnly, idempotent, non-destructive and open-world behavior, so the safety profile is covered. The description adds useful behavioral context beyond that: it discloses the data source (RDAP) and the full set of returned fields, including domain age and abuse contact, which helps an agent judge fitness for vetting tasks.

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: the first front-loads the core identity and the RDAP disclosure, the second covers use cases. The long enumeration of return fields is dense but earns its place as a scannable capability list; nothing is padded.

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?

An output schema exists, so the description need not explain return values, yet it summarizes them anyway for quick scanning. With annotations covering safety and a single well-documented parameter, the definition supplies everything needed to invoke the tool correctly; only sibling routing remains thin.

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, the schema already documents 'domain' and its no-scheme requirement. The description adds no additional syntax or format guidance 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+resource ('Registration intelligence for a domain via RDAP') and clarifies the mechanism with a parenthetical definition. It enumerates exactly what data is returned, so an agent can tell it apart from dns_lookup or tech_stack, but it does not distinguish itself from the sibling domain_report, which may overlap.

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 clear intent contexts – 'vet a company, assess a lead, or judge how established a domain is' – which tells the agent when this tool is appropriate. It stops short of naming alternatives or stating when-not-to-use (e.g. vs domain_report or dns_lookup), so routing among siblings is still partly inference.

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