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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is fully covered. The description adds the retrieval scope but says nothing about lookup failure behavior or whether values are computed or stored; with annotations doing heavy lifting, a 3 is right.

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?

A single front-loaded sentence with no filler; every listed field conveys real scope information.

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?

The output schema exists, so return-value explanation is not strictly needed, and annotations cover safety. The remaining gap is how to obtain a valid assembly_type and what happens on a miss, which the description leaves entirely unaddressed for an otherwise simple one-parameter tool.

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% for the single parameter 'assembly_type', and the description does not compensate: no format, allowed values, or pointer to list_assemblies as the source of valid identifiers. The agent must guess what string to pass.

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 ('Return') and a precise resource ('one assembly') and enumerates the returned facets (formula, dimensions, material factors, purchase increment, sources, material-pack lineage). This clearly separates it from list_assemblies, though the sibling is never named and 'assembly_type' is left undefined as a concept.

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?

There is no when-to-use, when-not-to-use, or prerequisite guidance. The singular 'one assembly' only weakly hints that it complements list_assemblies, and nothing tells the agent what to do when the requested assembly does not exist.

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