list_models

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

With no annotations, the description carries full burden. It fails to disclose essential behaviors like whether authentication is required, if the list is paginated, what fields are returned, or any rate limits. The minimal description leaves agents with unclear expectations.

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 a single sentence with no wasted words, but it sacrifices important information. Conciseness is acceptable, but the lack of structure (e.g., no separation of core behavior from usage notes) reduces usefulness.

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?

Given the tool has no parameters, no annotations, and no output schema, the description should provide context about the returned data (e.g., model IDs, names) and prerequisites. It fails to do so, resulting in an incomplete tool definition for effective use.

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 has zero parameters, and the baseline is 4. The description adds minimal meaning ('Get list of available OpenRouter models') beyond the empty schema, confirming the purpose of the tool.

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 clearly states the action ('Get list') and the resource ('available OpenRouter models'), which distinguishes it from siblings like 'get_model_info' (detailed info on a specific model) and 'compare_models' (comparison).

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 implies the tool is for retrieving the model list but offers no guidance on when to use it versus alternatives (e.g., 'get_model_info' for details, 'compare_models' for comparison). No explicit context provided.

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