list_models

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

With no annotations, the description carries the burden, and it does disclose that this is a GET against /v1/models and what the response contains (model ids plus upstream fields like object/owned_by). It says nothing about authentication requirements, rate limits, or whether listing is filtered/paginated, which are the remaining behavioral questions for a live API call.

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 short sentences, front-loaded with the action and endpoint, with the return contents appended. Nothing redundant or padded.

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?

No output schema exists, so the description must convey return values, which it does at a high level (model ids, object/owned_by). It stops short of describing the response envelope shape (e.g., whether results are wrapped in a data array), a minor gap for a simple list tool.

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; the baseline of 4 applies. The description correctly conveys that no inputs are required.

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 verb and resource ("List models available on RelayRouter") and even names the underlying endpoint GET /v1/models, so the operation is unambiguous. It does not explicitly contrast itself with the sibling chat_completion, but the read-only listing nature makes the distinction fairly evident.

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?

Usage is only implied: an agent can infer this is a discovery call to enumerate model ids before issuing a chat_completion. There is no explicit statement of when to use it, when not to, or what to do with the results.

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