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

The description goes well beyond the read-only/idempotent annotations by exposing the exact behavior: a deterministic division of the provided numbers with no hidden regulatory or customer-data logic. This is precisely the kind of behavioral context an agent needs to avoid assuming the tool does more than arithmetic.

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 operation and the key exclusions are each stated in a single short sentence, making the core behavior easy to scan. The opening phrase repeats the title verbatim, which is minor redundancy but not enough to hurt usability.

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 two-parameter pure calculation with read-only/idempotent annotations and an output schema, the description covers the operation and the absence of hidden rules. The only notable gap is the lack of an explicit numerator/denominator parameter mapping, though the parameter names make that mapping reasonably inferable.

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?

With 0% schema description coverage, the description needed to map the two agorot-denominated inputs to 'numerator' and 'denominator', but it only says 'divide the explicitly provided numerator by denominator'. The parameter names are suggestive, but the description itself does not resolve which input is which, so it only partially compensates for the missing schema descriptions.

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 ('Divide') and identifies the resource as 'payment to income', while the negative list ('No regulatory caps, eligibility verdict, fallback rates or customer identifiers') helps separate it from sibling calculators. It is clear, but it does not name an alternative sibling, so the differentiation is implied rather than explicit.

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 gives concrete context about when this tool is appropriate: it is a raw arithmetic ratio and will not apply regulatory caps, issue an eligibility verdict, use fallback rates, or look up customer identifiers. This is clear guidance, though it stops short of explicitly routing to a particular sibling when those features are needed.

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