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

With empty annotations, the description carries the full burden. It discloses that data is privacy-filtered, that it combines RDAP and DNS sources, and that risk signals are included. It does not state whether the operation is read-only, whether results are cached, or what failure/timeout behavior to expect, so transparency is partial.

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?

The definition is a single, front-loaded sentence with no filler. The fact list is dense and every phrase adds information.

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 lookup tool with no output schema, the description lists the major result categories and the required input, which covers most invocation needs. It omits when-to-use guidance and behavioral details such as response shape or timeout handling, but the core call surface is represented.

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 0%, so the description must explain parameters. It clarifies that 'domain' refers to a public domain and implies a hostname format, but it does not explain the optional timeoutMs parameter beyond the schema's numeric bounds. Since one of two parameters is left semantically unexplained, the description only partially compensates.

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?

The description states a precise operation ('combine privacy-filtered RDAP and DNS facts') and names the resource scope ('a public domain') plus concrete fact categories: registrar, age, expiry, DNSSEC, nameservers, MX, SPF, DMARC, and risk signals. This is enough to distinguish domain_intelligence from unrelated sibling tools like base_erc20_balance or web_read.

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 description implies a clear use case: fact-gathering for a public domain. It differentiates from opportunity/verification siblings by scope, but it never states when to prefer this tool over alternatives like web_read or probe, nor does it give exclusions or prerequisites. Guidance is implied rather than explicit.

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