bulk_search

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

With no annotations provided, the description carries full burden and does well by disclosing key behavioral traits: it mentions rate limiting, parallel processing capability, performance considerations, and what the tool returns (availability status, pricing, summary statistics). It doesn't cover error handling or authentication requirements, but provides substantial operational context.

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 description is perfectly structured and concise. It starts with the core purpose, then provides operational details, return values, and a concrete example - all in 6 sentences with zero wasted words. Every sentence adds value and the information is front-loaded appropriately.

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 tool with 3 parameters, 100% schema coverage, but no annotations and no output schema, the description does well by explaining what the tool returns and providing an example. It covers the main use case comprehensively but could benefit from mentioning error cases or limitations (e.g., what happens if domains exceed 100).

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. The description adds some value by reinforcing the 'domains' parameter's purpose ('domain names to check') and the 'tld' parameter's usage guidance ('single TLD for best performance'), but doesn't provide significant additional semantic context beyond what's already in the schema 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?

The description clearly states the tool's purpose with specific verbs ('check availability', 'searches') and resources ('multiple domain names', 'up to 100 domains'). It distinguishes from siblings like 'search_domain' (singular) and 'suggest_domains' (suggestion rather than availability checking). The example reinforces the bulk nature of the operation.

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 provides clear context for when to use this tool ('multiple domain names at once', 'up to 100 domains in parallel') and offers performance guidance ('use a single TLD for best performance'). However, it doesn't explicitly state when NOT to use it or mention alternatives like 'search_domain' for single-domain checks, which would be needed for a perfect score.

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