Diff Untested Models

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

There are no annotations, so the description carries the full behavioral disclosure burden. It does reveal output style ('trimmed per-model shape') and the filtering logic, but it does not explicitly confirm read-only/no-side-effect behavior, error conditions, or endpoint-related failure modes. The 'List' verb implies safety but does not state it.

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 with no filler. The core action is front-loaded, the distinguishing condition follows immediately, and the return-shape note is the only additional sentence. Every phrase 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?

For a simple list-style tool the description is mostly sufficient, but with no output schema and no parameter explanations, the vague 'trimmed per-model shape' and unspecified 'verbose' behavior leave meaningful gaps. An agent could call it, but not with full certainty about the result shape or option effects.

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 0%, so the description must compensate, but it only indirectly references the 'profile' parameter via 'profile's endpoint' and says nothing about the 'verbose' parameter. The agent is left to guess what verbose toggles and what the output shape actually contains.

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 states a specific verb ('List'), a specific resource ('downloaded LLM models on the profile's endpoint'), and a clear distinguishing condition ('no registry entry yet'). This differentiates it from siblings like list_models and read_registry by scope, and the parenthetical 'Workflow #3 discovery step' anchors its role.

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 provides clear context for when to use the tool: the discovery step of Workflow #3, specifically for models lacking a registry entry. It does not explicitly name alternatives or state when not to use it, so it stops short of a 5, but the intended usage is reasonably clear.

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