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

Annotations already declare readOnly, idempotent and non-destructive, so the safety profile is covered. The description adds genuinely useful behavioral detail beyond that: buyer names are hidden in quotes, quotes are in KRW with lead time, certain vendors (MEAN WELL, MORNSUN, CLAF) are quoted same business day, and results include a summary paragraph plus a purchasable part link.

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?

Front-loaded with the action and resource in the first clause, with returns described after. It is somewhat long and the final sentence about the summary paragraph could be trimmed, but every sentence carries usable information and there is no filler.

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?

There is no output schema, and the description fully compensates by enumerating what comes back (listings with quantity/price, KRW quotes with lead time, specs, same-spec alternatives, direct-supply status, summary paragraph, part-page link). Nothing needed to invoke or interpret the tool is missing.

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?

With a single parameter at 100% schema coverage the baseline is 3, but the description earns extra credit by clarifying that cable names such as 'F-CV 2.5SQ 3C' and 'HFIX 2.5SQ' are valid inputs, broadening the accepted format beyond the manufacturer-part-number example in 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?

The description states a specific verb and resource ('Look up one electronic or industrial part number') on a named platform (BIDON), and the word 'one' implicitly scopes it against the sibling search_parts. An agent can tell this is a single-part detail lookup rather than a bulk search without opening any schema.

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 makes the usage context clear (retrieve sale listings, quotes, specs, alternatives for a part) but never states when to prefer this over search_parts, nor any exclusion, and the sibling is not named. Usage is implied by the stated inputs and outputs rather than explicitly routed.

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