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

Annotations already cover the read-only, open-world profile. The description goes beyond them by disclosing conditional field presence (allow_offers/sold_at/final_price only for Fixed_Price lots), which materially affects how an agent should interpret results. It could still mention pagination/auth, 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?

Two dense sentences, front-loaded with what the tool returns before the parameter note and the conditional-field caveat. Every clause carries information, though the field enumeration is long.

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 an output schema present, the description needn't document return values, yet it usefully flags the lot-type-dependent fields and the slug's origin. Enough for an agent to call it correctly; minor gaps like error behavior remain.

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 0%, so the burden falls on the description, and it carries it: it defines the single parameter as the meta_slug obtained from a goldin_search result, giving format and origin not present 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?

Names a specific resource (one Goldin lot's full public detail) and enumerates the exact contents (title, bid/price, auction window, grading, images, prev/next pointers), so its scope is unambiguous against goldin_search, goldin_auctions, and goldin_categories.

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?

Explicitly states the input provenance — 'slug is the meta_slug from a goldin_search result' — which tells the agent it must first call goldin_search. It stops short of naming when-not-to-use or naming alternatives by name, so it is clear context without full routing guidance.

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