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

Annotations already declare readOnlyHint=true, so safety is covered; the description still adds genuine behavioral value by disclosing the return payload (including that cost is in cents) and that nested materials/labor rates are empty unless opted in. It omits pagination defaults and any rate-limit or permission notes, which keeps it short of 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?

One front-loaded sentence plus a compact API path reference; no filler. The semicolon-heavy clause listing returned fields makes it slightly dense to parse but nothing is wasted.

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 compensates by naming the returned fields and the opt-in expansion behavior, so an agent knows what it will receive. Missing only secondary details like default page size and authentication expectations.

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 all six parameters (q, page, page_size, sort_by, sort_direction, expand) are already documented in the schema. The description only adds a gloss on expand ("materials and labor rates"), which is useful but marginal — the 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 pair (list/search) and resource (price book services), then enumerates the returned attributes (name, task number, price, cost, taxable/online-booking flags). No sibling tool touches the price book, so the resource alone disambiguates it from list_customers/list_jobs/list_invoices.

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?

"List or search" implies the two entry modes, and the q parameter makes the search path clear, but there is no explicit guidance on when to reach for this tool versus a job/estimate line-item tool, and no stated prerequisites. Usage is implied rather than directed.

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