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

Annotations already declare readOnly/idempotent/non-destructive/closed-world, so the safety profile is covered. The description adds genuine behavioral context beyond that: results are manufacturer-catalog models with specs, each part reports how many BIDON sellers list it and whether BIDON supplies it directly, and stocked models are ordered first. No output schema exists, so this return-shape disclosure is valuable; only pagination/limits are unaddressed.

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 core condition and alternative, then organized with semicolons so each clause maps one category to its filter fields. Dense and long, but nearly every clause carries non-redundant information; it reads as one extended sentence where shorter bullets would scan better.

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 an 18-parameter, one-required-param tool with no output schema, the description covers trigger, category semantics, return contents (vendors, direct-supply flag, stocked-first ordering) and the handoff to lookup_part. Nothing an agent needs to call it correctly 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?

Schema description coverage is 100% and every field is documented, so the baseline is 3. The description goes further by grouping parameters by category (power supplies by output voltage and minimum power/current; breakers by type, poles, rated current; cables by ampacity, cores, installation; sensors by size, distance, mounting, output, contact, connection), which is the mapping the flat schema does not express.

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 ('Find parts by specification') plus the discriminating condition ('when no part number is chosen yet'), and enumerates exactly what each of the four categories can be filtered on. An agent can distinguish it from lookup_part (known part number) and search_parts 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?

Gives an explicit when-to-use trigger ('no part number is chosen yet, e.g. while designing a circuit or a distribution panel') and routes to the correct follow-up ('Call lookup_part on a part result for prices and listings'). The alternative is named with the condition that selects it.

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