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

Annotations already provide readOnlyHint: true, so the description need not reiterate safety. It adds value by specifying that it includes sensor comparisons and equivalent focal lengths, which are behavioral traits beyond the annotation.

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 concise sentences with no wasted words. Every sentence adds value: first states the core function, second states the extended feature (comparison). Perfectly front-loaded.

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 moderate complexity (2 params, no output schema, but clear calculation), the description explains the output (FOV angles, comparison). It could specify if results are in degrees, but it's sufficient for an agent to infer correct usage.

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 parameters. The description adds examples (ej. 24, 35) and explains sensor enums, but this adds only marginal meaning beyond the schema. Baseline 3 is appropriate.

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 it calculates horizontal, vertical, and diagonal FOV for given focal and sensor, and includes sensor comparison and equivalent focal. The verb 'Calcula' and resource 'ángulo de campo' are specific, and it distinguishes from other 'calcular' tools by its unique function.

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 use for FOV calculation but does not provide explicit guidance on when to use this tool versus alternatives, nor does it mention exclusions or prerequisites. Usage is only inferred.

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