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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world), so the description's added value is the disclosure of what comes back: quantities, packages and pinouts. It says nothing about result size, pagination or what happens when the inventory is empty, which is a modest residual gap for a list tool.

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 short sentences, front-loaded with the core action and return contents. The trailing note about designs preferring in-stock parts is marginally tangential but short and justifiable as motivation.

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 one-parameter, read-only listing with no output schema, the description says what the tool returns and why it matters, and annotations carry the safety semantics. Only the relationship to search_parts and any result-size behavior remain unaddressed.

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 the single optional 'search' parameter is documented in the schema. The description never mentions that the listing can be filtered, so it adds nothing beyond the structured data; baseline 3 applies.

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 (lists) and a clearly scoped resource (the parts the user owns), plus the fields returned: quantities, packages, pinouts. It does not, however, distinguish itself from the sibling search_parts, so an agent must infer the boundary between browsing owned inventory and searching a wider catalog.

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?

Usage is only implied: 'Designs prefer parts in stock' hints at why reading the inventory matters, but there is no explicit statement of when to call this rather than search_parts or get_part, and no exclusions or prerequisites.

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