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

Annotations already declare readOnlyHint and openWorldHint, so the safety profile is covered. The description adds genuinely non-annotated behavioral context: that allow_offers/sold_at/final_price appear only for Fixed_Price (Buy Now) lots and are otherwise absent, which prevents an agent from misreading missing fields as an error.

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, both earning their place: the first front-loads the returned payload, the second gives the parameter provenance and the Fixed_Price field caveat. No filler or repetition.

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, yet the description still summarizes the payload and flags conditionally-present fields, which is exactly the context a detail endpoint needs. With one required param, full schema coverage, and both annotations supplied, nothing an agent needs to call it correctly is missing.

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% and the single Slug field is fully documented in the schema, including its origin in a goldin-search result — the description's slug note essentially restates the schema. Baseline 3 is appropriate since the schema does the heavy lifting.

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 (retrieve one Goldin lot's full public detail) and enumerates the exact field groups returned: title, description, bids, auction window/status, grading, images, and prev/next lot pointers. It also distinguishes itself from the sibling search tool by requiring a slug that comes from a goldin_search result.

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 establishes the prerequisite workflow clearly: the slug must come from a goldin_search result, so an agent knows to search first and fetch detail second. It stops short of naming when NOT to use it (e.g. use goldin_search/goldin_auctions for browsing), so it is clear context without explicit exclusions.

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