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

Annotations already declare readOnlyHint, idempotentHint and openWorldHint=false, so safety is covered. The description adds genuinely new behavior: results are capped at 10 matches and each match carries its domain, which tells the agent how to paginate/limit expectations. No auth or rate-limit detail, so not a 5.

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: purpose and input formats first, return shape and next-step routing second. No filler or restated name/title.

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 does carry the return-value burden and discharges it reasonably ('up to 10 matches with their domains'). It omits edge behavior such as no-match results or result ranking, which would be needed for a 5.

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 the schema already defines query as 'Company name or domain, at least 2 characters.' The description goes slightly beyond it by exemplifying both accepted forms ('squarespace' for name, 'stayfi.com' for domain), which is the only added meaning available for a single-parameter tool.

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?

Specific verb (Find) plus a precisely scoped resource (companies with a public sponsorship page) and concrete input examples. It also implicitly separates itself from the sibling get_sponsor by describing lookup-by-query rather than detail-by-domain.

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 states the search context (by domain or name) and routes the agent onward: 'pass a domain to get_sponsor.' That is clear use guidance with a named follow-up, though no explicit when-not-to-use or disambiguation from list_trades/get_trade_board is given.

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