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

Annotations already declare readOnlyHint, idempotentHint, non-destructive and closed-world, so the safety profile is fully covered. The description adds only that the result is expressed in meters and that the computation is pattern-based; it says nothing about precision, rounding, or how unusual garment/width combinations are handled.

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?

Four short sentences, front-loaded with the core computation and with no filler. The 'Returns meters of fabric' sentence is largely redundant given an output schema exists, which is the only real waste.

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 a rich schema, full annotations, and an output schema, the definition supplies everything needed to invoke the tool correctly. The remaining gap is sibling disambiguation against the other fabric/curtain calculators, which matters in a catalogue of this size.

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%, with all three parameters documented and two constrained by enums, so the schema carries the semantic load. The description merely restates the input list ('garment type, size, fabric width') without adding units, valid ranges, or meaning beyond the schema, which is the expected baseline when coverage is this high.

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 gives a specific verb and resource: 'Compute fabric meters needed for a garment by pattern,' which tells the agent exactly what comes out (meters of fabric) and what it is for (sewing). It does not, however, distinguish itself from close siblings such as calculate_fabric_yardage, calculate_curtain_fabric, or calculate_knitting_yarn, so an agent choosing between fabric calculators gets no routing help.

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?

'Use for sewing' is a weak domain hint rather than a real when-to-use condition, and there is no statement of when NOT to use it or which sibling to prefer. The pointer to list_bundles mentions 'related textile-mode calculators' but does not name the competing tools directly, so the guidance is implied rather than explicit.

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