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

Annotations already establish readOnly, idempotent, non-destructive and closed-world, so the description's real contribution is return behavior: a cap of up to 8 creators, the specific fields returned, the caveat that handle and profile link only exist for creators with a public profile, and a call-to-action link to start a gifted roster. That is genuinely additive. The gap is that it never explains the relationship between the small preview cap and the full directory, which matters for an agent deciding whether one call is enough.

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?

Three sentences, front-loaded with purpose and scope, then return contents, then usage triggers — a sensible ordering with no filler. The middle sentence is a long field list, but each item is a real decision input for an agent.

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?

With no output schema, the description correctly carries the burden of describing the return payload and does so at field level. What is missing is how much of the directory this represents and what an agent should do when 8 results are insufficient.

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 coverage is 100% and each of the four parameters is already documented with types, defaults, enum and examples, so the schema does the heavy lifting. The description only restates that platform and country are optional filters while niche is the driver, adding no format or edge-case detail beyond the schema; 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 ('Searches Newcollab's directory of vetted UGC creators') and immediately narrows scope with 'by niche, with optional platform and country filters.' An agent knows exactly what is queried and what dimensions constrain it.

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 closing sentence gives concrete when-to-use triggers ('product seeding, PR packages, or TikTok or Instagram ads') and names the target persona (UGC creators or micro-influencers). It lacks any when-not-to-use or exclusion guidance, though with no sibling tools there is little to disambiguate against.

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