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

Annotations already cover read-only, idempotent, non-destructive and closed-world, so the description's added value is the credential requirement (public, no auth) and the disclosure that the floor price is never returned — a meaningful data-boundary fact an agent cannot infer from the schema. It omits anything about response shape or rate limiting, keeping 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?

Front-loaded with the core action and handle requirement before the enumeration and the product_id filter. Four sentences, all carrying information; the enumeration is dense but each clause maps to real returned data.

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 carries the burden of describing returns and does so by listing the specific terms exposed, plus not-found behavior. It doesn't say whether the response is a single object or per-product array, which is the one remaining ambiguity for a caller.

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 description coverage is 100%, so both parameters are already documented as the seller's public handle and the seller's product id. The description only adds the intent hint that product_id narrows the result to one product, which is marginal beyond 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 — "Read a seller's negotiable terms by their public handle" — and enumerates exactly what is returned (open products, list price/currency, offer count, counter duration). The "Public: needs no credential" framing implicitly separates it from the authenticated get_offer_settings sibling, but that sibling is never named, so differentiation stops just short of explicit.

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 operational context: pass product_id to narrow to one product, and states the three not-found conditions (unknown handle, offers off, product off). It never names an alternative tool or says when to prefer get_offer_settings versus this one, so the routing guidance is implicit rather than explicit.

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