Chat with a UnoRouter model

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

With no annotations, the description takes on the transparency burden. It discloses that :free models cost nothing, have a light per-model rate limit, and that 429 errors can be mitigated by rotating models – useful behavioral context. It does not mention authentication, error handling beyond 429, or streamed responses, but the core behavior is well covered.

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 two compact sentences: the first states the core function, and the second provides guidance on model selection and rate limits. Every sentence adds value without redundancy or unnecessary detail.

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 chat tool with no output schema, the description sufficiently states that it returns the reply. It covers model selection and cost/rate-limit nuances. It omits details about the exact response shape or error conditions beyond 429, but these are inferable for a simple chat invocation. The guidance on siblings adds useful context.

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 60% (model, prompt, system have descriptions). The description adds meaning for the model parameter by linking it to search_models and explaining the :free suffix, but does not elaborate on prompt, system, max_tokens, or temperature meanings beyond the schema. It partially compensates for the uncovered 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 clearly states 'Send a single prompt to any UnoRouter model and return the reply' – a specific verb, resource, and scope. It distinguishes itself from siblings (search_models, get_pricing) by focusing on the chat/completion action.

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 explicitly instructs to 'Use search_models to find model IDs', naming the alternative tool. It also provides practical usage guidance about :free models, rate limits, and rotating models on 429 responses, which is valuable for choosing and using the tool correctly.

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