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

Annotations already establish a safe read-only, idempotent, closed-world operation; the description adds concrete returned fields such as token, ask, expiry, order hash, and protocol address, plus passport/proof context and a no-endorsement/no-valuation disclaimer. No contradiction with readOnlyHint is stated; the “steps to fill the listing” are presented as information, not as an action the tool performs.

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?

The purpose is front-loaded, but the description is a dense run-on that packs marketplace fields, passport/proof details, fill instructions, holding benefits, fallback behavior, and disclaimers into very few clauses. It is informative rather than wasteful, but the structure makes it harder to scan than it should be.

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?

No output schema exists, so the description must carry return semantics; it identifies the listing fields and the fallback collection output, and adds relevant context about Origin Passports and proofs. For a one-parameter read-only tool with annotations already covering safety, this is complete enough to call 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?

The only parameter is collection, and the schema already covers it fully with a slug example. The description adds meaningful optional behavior beyond the schema: omitting collection returns the collections that have a market answer.

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?

The opening clause specifies the resource and condition clearly: works that can be bought now on the open market, including artist listings and collector resales. It does not use an explicit verb or distinguish itself from sibling tools like get_asset or get_proof, so an agent can identify the domain but must infer the list/retrieve shape.

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 states the no-collection mode explicitly: without a collection, it lists collections that have a market answer. The collection mode is also clearly framed as market listings, but there is no explicit guidance on when to prefer sibling tools such as get_asset or get_evidence.

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