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

Annotations already declare readOnly/idempotent/non-destructive, so the safety profile needs no restatement. The description adds that hems and pattern repeat are included in the computation and that it returns fabric length to buy, which is useful scope context, but nothing about units, edge cases, or how the result is derived. Adequate but thin beyond annotations.

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 purpose and the return value, with no filler. The structure is tight; the only issue is the inaccurate input list, which is a correctness problem rather than a verbosity one.

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?

An output schema exists so return values need not be spelled out, and the safety annotations cover the risk profile. For a simple computation the description is nearly sufficient, but the phantom 'pattern repeat' input leaves the parameter story inconsistent with the schema.

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 lists 'pattern repeat' as an input when no such parameter exists in the schema, and omits num_panels entirely. This mismatch risks sending the agent looking for a nonexistent field, so it detracts rather than adds value over the schema.

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?

States a specific verb and resource: computing fabric meters for curtains, with scope (hems, pattern repeat). An agent can identify the domain (sewing/textile) clearly. However, it does not differentiate itself from close siblings like calculate_curtain_width, calculate_fabric_needed, or calculate_fabric_yardage, so the boundary is blurry.

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 the only when-to-use signal and it is minimal. The only alternative mentioned is list_bundles, which is a discovery tool, not a competing calculator. It never says when to prefer this over calculate_curtain_width or calculate_fabric_needed, leaving the agent to guess among several similar siblings.

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