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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds useful scope context ('full published set', editorial and sale-campaign) but says nothing about pagination, rate limits, or whether the list is stable — modest added value beyond the annotations.

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?

A single front-loaded sentence that identifies the resource, its scope, and its downstream use with zero waste. Nothing is padded or redundant.

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, so return values need no explanation, and annotations cover safety. With no parameters and a simple enumeration, the description supplies what an agent needs, though it could note list stability or freshness.

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 tool takes zero parameters, so the baseline is 4; there are no parameter semantics to clarify. The description correctly implies a parameterless enumeration rather than misrepresenting any input.

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 description names a specific resource — 'The RealReal's full published set of curated editorial and sale-campaign collection slugs' — and explicitly distinguishes it from the sibling therealreal_collection by noting these slugs feed that tool's slug parameter. An agent can tell it apart from therealreal_categories/designers without opening any 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 clear relational context: these slugs are 'usable directly against therealreal_collection's own slug parameter', which signals the discover-then-fetch workflow. It does not, however, state explicit when-not conditions or name alternative sources, so it stops short of full routing guidance.

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