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

With no annotations, the description carries the full burden and delivers unusually useful context: the two status values and their meaning, the guarantee that filling-up parts are usable today, and the strong warning that price_usd is null and for_sale false on every kit so those fields must not be used to infer status. It omits return shape and pagination behavior, which keeps it from 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?

It is front-loaded with the definition and the usage trigger before the status/pricing caveats, and every sentence carries operational value — particularly the anti-pattern warning about not quoting kit prices. The closing 'Use get_kit to fetch either' is compressed to the point of ambiguity, a minor structural blemish.

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 no annotations, no output schema, and no parameters, the description supplies the context an agent actually needs to call and interpret the result: what a kit is, when to prefer one, and how to read the status and price fields it returns. It could be slightly more complete by stating that it returns the full set of kits, but nothing critical 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?

The tool takes zero parameters, so per the baseline this scores 4. The description correctly spends no space on parameter semantics and instead uses the room for domain context.

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 defines what a kit is ('coherent sets built to one palette and one grid') and implicitly establishes this as the enumeration tool, and it explicitly contrasts with get_kit for fetching a single one. The verb 'list' is only carried by the tool name rather than the prose, so it stops short of a fully explicit verb+resource statement.

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 clear selection rule — 'Reach for a kit when the user is building a whole environment rather than looking for one object' — which effectively distinguishes it from object-level siblings like search_assets or get_asset. It also routes to get_kit, though 'to fetch either' is ambiguous about what 'either' refers to.

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