calculate_ring_size

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

With no annotations, the description carries full burden for behavioral disclosure. It states inputs as 'circumference mm or diameter mm', but the input schema only includes 'circumference_mm', contradicting the description. It also fails to explain the 'from_system' parameter or what it represents. This inconsistency and omission reduce transparency.

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 short (three sentences) and front-loaded with purpose. However, it omits critical information about the 'from_system' parameter, making it somewhat incomplete. Conciseness is fine, but at the expense of necessary details.

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 the tool's complexity (ring size conversion across systems) and lack of annotations, the description should cover input requirements and behavior more thoroughly. It mentions output in multiple systems but fails to explain the required 'from_system' parameter or clarify the input discrepancy (circumference vs diameter). The output schema exists but the description should still provide coherent 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 0%, so the description must compensate. It lists 'circumference mm or diameter mm' as inputs, but the schema has only 'circumference_mm' and an undocumented 'from_system' parameter. The description does not mention 'from_system' at all and incorrectly suggests diameter is accepted. This adds confusion rather than clarity.

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 the tool's purpose: 'Find ring size in EU/US/UK/JP given finger circumference or diameter.' It uses a specific verb ('Find') and resource ('ring size'), and explicitly mentions the context 'jewelry shopping'. Although it doesn't differentiate from the sibling 'calculate_ring_size_convert', the purpose is unambiguous.

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 suggests use for 'jewelry shopping' and references list_bundles for related calculators, providing some context. However, it lacks explicit guidance on when not to use this tool (e.g., for converting existing ring sizes) and does not mention alternatives like 'calculate_ring_size_convert'. The guidance is adequate but minimal.

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