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

Annotations already establish that this is a read-only, idempotent, closed-world calculation, so the safety profile is covered. The description adds useful behavioral context by saying the result includes the GS1 allowed range, giving agents a sense of the return content even without an output schema.

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, front-loaded sentence with no unnecessary wording. It communicates the operation, the conditional inputs, and the returned range efficiently.

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 simple three-parameter calculation tool with no output schema, the description provides enough context to call it correctly. It could be slightly more explicit about supplying either magnification or X-dimension depending on type, but the essential behavior is clear.

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 coverage is 100%, so the baseline is 3, but the description adds meaningful mapping beyond the schema: GS1 magnification applies to retail and carton types, while X-dimension applies to other types. This helps an agent choose between the optional numeric parameters based on the barcode type.

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 states a specific verb and resource: it returns the printed size of a barcode type under either GS1 magnification or X-dimension. It is clearly a sizing/calculation tool rather than a creation or validation tool, though it does not explicitly name sibling alternatives for contrast.

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 when to use magnification versus X-dimension by noting retail and carton GS1 types versus other types, but it does not explicitly state when to use this tool over siblings or exclude any cases. Usage is inferable from the parameter guidance rather than directly specified.

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