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

Annotations only declare readOnlyHint and openWorldHint; the description adds substantial behavioral detail beyond that: it caps results at the first 20 of Booksy's own search page plus a total count, and it discloses the metered cost ($0.002 USDC per successful call via x402, failed calls not charged) including accepted payment chains. Cost and result-cap semantics are exactly the kind of context annotations cannot express.

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 dense sentences that front-load 'what you get' before constraints and pricing. Every clause carries information, though the field enumeration in sentence one is long and could be trimmed slightly. No filler or restatement of the 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?

An output schema exists, so return shapes need not be explained, yet the description still summarizes the payload, states the result cap and total count, explains region scoping, and discloses pricing and payment mechanics. For a read-only, 3-parameter, paid search tool this covers everything an agent needs to decide and invoke correctly.

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%, so the baseline is 3, but the description adds real meaning: it explains that regionId is the number appearing in a Booksy search URL (with concrete examples already in the schema) and that omitting it widens to US-wide, and it reinforces the 20-result limit. Meaningful marginal value over the schema without re-dumping the category enum.

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+resource: businesses listed on Booksy (US) for a category and region, and enumerates exactly what fields come back (address, coordinates, rating, socials, Booksy Pay, promoted flag, services with price/duration). This is clearly distinguishable from the other directory siblings such as b2b_yellowpages or b2b_google_maps because it names the source and the niche vertical.

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?

It implies usage through constraints: category is required and regionId narrows the search, with 'without it the search is US-wide'. But it never says when to prefer this over the many other local-business directories in the sibling list, nor does it state exclusions or preconditions. Adequate but leaves routing to inference.

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