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

Annotations already declare readOnly, idempotent, non-destructive, non-open-world, so the safety profile is covered. The description adds real behavioral context beyond that: results carry per-fact provenance, conflicts are surfaced rather than resolved silently, and responses are paged with next_offset. Missing are failure modes for a not-found part and whether provenance/conflicts can be suppressed.

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, both earning their place: the return contents come first, paging second. No restatement of the title and 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?

With no output schema, the description carries the return-shape burden and does so well by naming the per-pin fields and the provenance/conflict data. The paging loop is gestured at but not fully closed (how to use offset alongside next_offset), which is the only notable gap for a read-only lookup 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 coverage is 33%: only 'query' is documented in the schema, and limit/offset have no descriptions there. The description partially compensates by explaining paging and that next_offset is the next page's offset, but it never pins down what offset/limit do relative to that loop, nor the 64 cap.

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 ('Returns the pinout of an exact part') and enumerates the returned facts (function, voltage, direction, polarity, sources, conflicts). The 'exact part' qualifier implicitly separates it from search_parts, but no sibling is named explicitly, so differentiation is inferred rather than stated.

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: the agent learns it must already hold an exact part name, catalog id, or part number, and that it should not expect fuzzy lookup. There is no explicit when-to-use vs get_part / get_part_capabilities / search_parts, and no statement of what happens when the part is unknown.

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