model_routing

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

With no annotations provided, the description carries the behavioral disclosure burden. It does well by stating that all parameters are optional, defaults mirror an existing calculator, and the response includes result, formula, interpretation, and a cite_as sentence. It does not explicitly say the operation is read-only or side-effect-free, but the calculator framing strongly implies it.

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 compact, information-dense sentences contain the purpose, scope, default behavior, and response composition without repetition. The key question is front-loaded, and every clause contributes useful information.

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 three optional numeric parameters and no output schema, the description adequately explains what the tool returns: result, formula, interpretation, and a cite_as sentence. It could be slightly stronger with an explicit output format or an example, but nothing essential for correct invocation is missing.

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 ratio, share, and spend with units and defaults. The description adds the context that all parameters are optional and that defaults match the interactive calculator, but it provides no additional parameter-level semantics.

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 identifies the tool as a calculator for monthly and yearly savings from routing workload to a cheaper model tier, naming the core resource and computation. It stops short of a direct imperative verb like 'calculate' and does not explicitly distinguish itself from sibling cost-related tools.

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?

There is no explicit guidance on when to choose this tool over alternatives such as token_cost or token_burn. The description only implies its use for model-routing savings questions and notes defaults mirror an interactive calculator, but it never states conditions or exclusions.

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