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

No annotations are provided, so the description must disclose all behavioral traits. It mentions converting inputs to outputs but does not disclose that cropFactor and sensorWidthMm are required inputs, nor how sensorPreset and cropFactor interact. This leaves ambiguity about the calculation behavior and necessary inputs.

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 a single sentence that front-loads the primary conversion purpose and lists the main inputs and outputs. It is compact and free of fluff, although the opening phrase repeats the tool's title before the substantive content.

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?

With no output schema, the description should clarify return formats and computational assumptions, but it merely says 'equivalent focal, aperture, and field of view' without specifying units or the type of field of view (e.g., horizontal degrees). It also fails to explain the relationship among sensorPreset, cropFactor, and sensorWidthMm, which are all required inputs, leaving significant gaps for a calculator of this complexity.

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 for parameter meanings. It names 'focal length, aperture, and sensor' but omits cropFactor and sensorWidthMm entirely, and provides no units, constraints, or enum explanation. This gives minimal semantic help beyond the raw schema names.

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 function: converting focal length to a full-frame equivalent using crop factor, and also computing equivalent aperture and field of view. The specific verb 'Convert' combined with the resource scope ('focal length to a full-frame equivalent by crop factor') distinguishes it from sibling calculators like depth_of_field_calculator or aspect_ratio_calculator.

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 implies usage by showing the inputs and outputs, but it does not explicitly state when to use this tool versus alternatives. There is no mention of exclusions or contrast with related calculators, so the agent must infer the appropriate context.

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