OpenBait lookalike domains

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

Annotations already declare readOnlyHint, openWorldHint, and idempotentHint, so the restating of 'Read-only' is redundant rather than additive. What the description does add is genuinely useful behavior: it says the check resolves each candidate in DNS and inspects the front page, and names the possible outcomes (brand-name page, redirect to brand, other live site, nothing). It doesn't mention latency or result volume, which for an open-world network scan would be useful.

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 tight sentences, front-loaded with the core action, then the variant list, then the evaluation behavior. Every clause carries information and there is no filler.

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?

Output schema exists, so return shape needn't be spelled out, yet the description still previews the outcome categories the agent will see. Combined with the read-only framing and the external reference, nothing needed to invoke this correctly is missing.

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, and the schema already documents it at 100% coverage with an example ('example.com or https://www.example.com'). The description adds nothing about the domain argument beyond what the schema states, 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 (find lookalike domains of a brand's website) and enumerates exactly what kinds of variants are generated: typos, swapped letters, look-alike characters, added words, other TLDs. An agent knows precisely what this tool produces without opening the 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?

The scope is clear — given a brand domain, it enumerates and evaluates lookalikes — and the reference to the equivalent openbait.com tool gives the agent a concrete mental model. There are no sibling tools to route against and no explicit 'do not use for X' exclusion, which keeps it just short of a 5.

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