list_available_models

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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint, so the safety profile is covered. The description adds that it covers every available provider CLI and takes no arguments, but it does not disclose behavioral details such as how 'available' is determined, whether provider CLIs are probed at runtime, or what happens when no providers are installed. This is acceptable but not rich.

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 sentence that leads with the action and resource, includes the no-argument note, and clarifies the relationship to a sibling tool. Every clause earns its place with no redundancy or filler.

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 no-argument, read-only, idempotent listing tool, the description along with the annotations is complete. It states what is listed, the scope, the no-input requirement, and how it relates to the per-provider alternative. There is no missing information an agent would need to select or invoke this tool correctly.

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?

With zero parameters and a schema description coverage of 100%, the schema already fully defines the input. The description adds the useful explicit statement 'takes no arguments', which reinforces the empty schema, but it does not add meaning beyond that, so the 0-parameter baseline of 4 is appropriate.

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 uses a specific verb ('List') and a clear resource ('models and capabilities for every available provider CLI'). It also explicitly distinguishes itself from the sibling 'list_models' by framing itself as the cross-provider complement, so an agent can tell the tools apart.

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?

The phrase 'complements per-provider list_models' clearly signals when to use this tool: when you need a cross-provider overview rather than a single provider's list. It could be even stronger with explicit when-not-to-use language, but the context is clear enough.

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