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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the safety profile is covered. The description adds that facet counts are optional and that search is scoped to a single family, but says nothing about pagination behavior, default/max result sizes, or the cost of enabling facets.

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 sentences, zero filler, with the core capability front-loaded and the disambiguating context trailing. Nothing is repeated from the schema or annotations.

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 six-parameter tool with no output schema and zero schema documentation, the description is serviceable but incomplete: it does not tell the agent how to construct the filters/sort objects or what a result record contains. Adequate to choose the tool, thin for invoking it correctly on the first try.

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%, and the filters and sort parameters are free-form objects with additionalProperties true, so the description carries the whole burden — it usefully names the filter axes (numeric ranges, categorical, MPN substring, manufacturer) and with_facets. It never explains the shape of the filters dict, nor the meaning of sort, limit, or offset, so the gap is only partly closed.

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 — parametric search over one parts family — and enumerates the searchable axes (numeric ranges, categorical values, MPN substring, manufacturer). The clause 'this is the catalogue question ... and needs no converter design' hints at what it is not, but never names a sibling, so differentiation is partial.

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?

Frames the use case as the 'catalogue question' and rules out scenarios needing converter design, which is useful framing. However, no sibling is named (part_details, recommend_parts, cross_reference are all adjacent) and there is no explicit when-not guidance for choosing among them.

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