List Available Models

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

Annotations already declare readOnlyHint and idempotentHint, but the description adds no behavioral context beyond the platform name. It does not mention output format, pagination, ordering, or any other side effects, making the description minimally informative beyond the structured data.

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?

The description is one short, front-loaded sentence: 'List available models on OpenRouter' with no redundancy or unnecessary detail. Every word 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 trivial no-parameter list tool, the description is barely adequate. It does not specify the return format (e.g., list of model IDs, names, metadata) and leaves ambiguity about whether it lists all models or a filtered subset. However, given the simplicity, the gap is not severe.

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 input schema has zero parameters, so the baseline of 4 applies. No parameter descriptions are needed, and the description appropriately does not attempt to elaborate on nonexistent parameters.

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 the action (list) and resource (available models) with the platform (OpenRouter). It does not explicitly differentiate from sibling tools like filter_models or recommend_model, though the verb and scope are clear.

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 description provides no guidance on when to use this tool versus alternatives such as filter_models or recommend_model. It does not mention whether this returns all models, any prerequisites, or when to prefer another tool.

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