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

With no output schema, the description carries the full burden of describing returns, and it does: letters, syllables, length note, pronunciation/typing hazards, spelling-ambiguity risk bands, a domain form, and close matches via edit distance, sound-key and containment. It also explicitly disclaims availability and legal claims, preventing a false confidence the annotations alone would not flag.

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 core action and the required/optional parameters come first, and the negative scope closes the description usefully. The middle enumeration of per-name outputs is dense and runs long as a single sentence, but nearly every clause carries information an agent would otherwise have to guess.

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, no annotations beyond read-only safety, and three parameters: the description covers all three, spells out the return contents, and states the exclusions. Nothing an agent needs to select or invoke this tool 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?

Schema description coverage is 100%, so the baseline is 3, but the description adds meaning by explaining what `existing` is actually used for (edit-distance, sound-key and containment comparison against candidates) and that `tld` only shapes the domain form rather than triggering a lookup. These are genuine semantics beyond the schema's one-line parameter descriptions.

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?

Opens with a specific verb and resource ('Screen brand name candidates') and immediately scopes the tool as a language and usability screen only, explicitly excluding trademark, legal, availability and foreign-language meaning. That scoping cleanly separates it from nearby siblings such as check_naming_conventions and tagline_review without needing to name them.

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 the input shape (names 1-30 required, existing optional, tld default com) and gives clear negative guidance on what it does not cover, which tells the agent when this tool is and isn't appropriate. It stops short of pointing at a specific alternative tool for trademark or availability checks, so it falls 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.