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

Annotations already cover readOnlyHint and openWorldHint, so the safety profile is settled. The description adds a genuinely useful behavioral constraint not in the structured data: Listings only ever contains ACTIVE listings, clarifying what the returned page will and will not include.

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 tight sentences, front-loaded with what the tool returns and its scope. No filler; every clause (shop view, username provenance, active-only) earns its place.

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 explain return values, and it covers the tool's purpose, input provenance, and a non-obvious scope constraint. 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 description coverage is 100%, so page and limit are fully documented in the schema and need no compensation. The description adds provenance meaning for username, but that is a modest supplement rather than filling a documentation gap.

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: returns a Grailed seller's public profile plus a page of their active listings, and explicitly names the underlying view ('Grailed's own shop view'). This distinguishes it from grailed_search and grailed_seller_reviews without needing to open a schema.

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 gives a useful sourcing hint for the username (from a listing's own seller.username field) and implies active-only scope, which hints at using grailed_sold_listings for sold items. However, it never explicitly states when to use this versus grailed_seller_reviews or grailed_sold_listings, leaving the routing to inference.

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