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

Annotations already declare readOnlyHint=true and openWorldHint=false, but the description adds genuinely new behavior: it costs one search credit, it returns totals plus ranked exhibitors with their listings, and filters scope to the exhibitors returned rather than the listings. That last point is a non-obvious semantic an agent could easily get wrong.

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 short sentences, each carrying distinct information: purpose, return shape, query convention, filter scoping, and search cost. Zero filler and the scope statement is front-loaded.

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 exists, yet the description covers the return shape, the search-credit cost, and filter scoping — the main things an agent needs. Minor gaps: 'phase' and 'limit' semantics are not elaborated, and no alternative tool is named, but for a 5-param read-only search this is close to 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?

With 60% schema coverage, the description compensates by clarifying that optional filters ('type', 'certificate', presumably 'phase') apply to the exhibitors returned, not to the listing match — a real semantic addition the schema does not state. 'query' is reinforced as product words only, matching the schema; 'limit' is left unexplained but is bounded 1-10 in the schema.

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 ('Search exhibitors' product listings and profiles') plus scope ('across the whole fair'), and the return shape ('totals and best-matching exhibitors with their matching listings'). It is distinguishable from get_exhibitors and check_fit by implication, though no sibling is named explicitly.

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?

Gives concrete usage guidance: 'Use product words only (e.g. bamboo cutting board)' and 'Spends one search', which signals a budget/quota consideration. It does not explicitly say when to prefer get_exhibitors or check_fit instead, so it stops short of full alternative routing.

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