routeLLM

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

With no annotations provided, the description carries the full burden and communicates key behavior well: it explicitly states Zero Data Retention default, the energy-based provider suffix logic, and the crucial fact that it does NOT send the request. The one gap is not disclosing auth requirements (API keys) or error behavior for unknown presets, but the provided behavioral context is strong.

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 compact (three sentences) and front-loaded with the core purpose in the first sentence. Each sentence earns its place: purpose, energy logic, data retention, and the explicit non-sending behavior. It loses the top score only because it crams several distinct facts (energy mapping, retention, non-sending) into a somewhat dense structure, but there's no waste or redundancy.

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 5 parameters with 100% schema coverage, a nested object field, and no output schema, the description is appropriately complete. It adds the non-obvious details the schema can't convey: the energy→suffix mapping, the Zero Data Retention default, the overrides merge priority, and the crucial non-sending behavior. There is no output schema, but the description explicitly states what it returns (URL, headers, body), compensating well.

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 100%, so the schema already documents every parameter, including the energy enum values with direct mapping to suffix behavior. The description adds context about energy mapping (floor/nitro/base) and overrides merging semantics ("merged in last") which aligns with and enriches the schema. The description reinforces rather than extends, which is appropriate given full coverage. Baseline 3 is correct.

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 ("Build a ready-to-send OpenRouter chat-completion request body") with a clear resource (named preset + energy budget). It distinctly states what it does NOT do (sends the request), which is an excellent positive and negative definition. Despite no siblings being provided, the purpose is unambiguous and self-contained.

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 clearly narrates the energy-preset selection logic (low→:floor, high→:nitro, balanced→base slug), telling the agent when to use which energy value. It doesn't explicitly name alternatives or exclusions, since no sibling tools exist to differentiate against. The guidance is strong on the core decision, slightly lighter on external context.

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