List models

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

With no annotations, the description carries the full burden and does reasonably well: 'list' implies a non-mutating read, and it discloses the returned fields plus a governance distinction (shippable vs prototype-only). It stops short of stating read-only guarantees, auth requirements, or cost-units/precision, so it is not fully transparent.

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 sentences, no filler. The core deliverable ('every model ... with its Space, licence and rough cost') is front-loaded, and the usage rule follows immediately in the same breath.

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 structure need not be spelled out, yet the description still summarizes the payload and adds the one thing the schema cannot convey: that the list encodes a ship/prototype governance decision. Nothing needed 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?

The tool takes zero parameters, so there is nothing to disambiguate; baseline is 4. The description correctly adds no parameter chatter, keeping it a pure inventory call.

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 resource ('every model this server can reach') and enumerates what each entry carries (Space, licence, rough cost). An agent can distinguish this inventory tool from the generate_* siblings purely from the description.

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?

Gives an explicit trigger: 'Read this before generating.' It explains the selection consequence (which models may ship vs prototype-only) rather than just naming an alternative sibling, but it never names model_sheet or another route as a substitute.

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