search_domains

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

With no annotations supplied, the description takes on full transparency duty. It discloses result grouping semantics (AVAILABLE/TAKEN/UNKNOWN) and the critical behavioral rule that UNKNOWN entries are unverified and must not be treated as available, preventing misuse.

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?

Four sentences pack the core purpose, usage, and output semantics without redundancy. The example in parentheses makes the one-to-many matching instantly clear.

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?

The description covers purpose, alternatives, output structure, and an important data-interpretation caveat. It lacks only granular return/error details, but given the tool's simplicity and no output schema, this is sufficient.

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?

Both parameters already have detailed schema descriptions (query format, tlds format and default), so the description adds little beyond the example. Schema coverage is 100%, warranting a 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?

The description opens with a specific action and resource ('Check ONE name across MANY TLDs') and immediately differentiates from the sibling tool check_domain, making its scope unmistakable.

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?

Explicitly states when to use ('when comparing extensions for the same word') and when not to ('for a single known domain use check_domain instead'), providing clear decision guidance.

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