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

Annotations already declare readOnlyHint, idempotentHint, non-destructive and closed-world, so the safety profile is covered. The description adds genuine domain semantics beyond that: the returned data is catalog reference data, not verified installed-part or protection evidence, which affects how the agent should trust and cite it.

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, front-loaded with the action and payload, followed immediately by the important limitation. No filler, no restatement of the tool name or title.

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 an output schema present, return-value detail need not be repeated, and annotations cover the safety profile, so the description only needs purpose, payload and the catalog-vs-verification caveat — all present. The one gap is that catalogId's accepted format is left entirely to the schema.

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% for the single catalogId parameter, but the description's 'one exact catalog component' implies an exact-ID (non-fuzzy) lookup, which is meaningful. It still adds no format, casing, or pattern guidance beyond what the schema's regex and maxLength already enforce, so this is baseline rather than compensating.

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 ('Read one exact catalog component') and enumerates the payload (terminal IDs, electrical specs, known configuration). The phrase 'one exact' implicitly contrasts with the sibling search_components, so an agent can distinguish single-ID lookup from search without opening a 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 second sentence draws a clear scope boundary: catalog data does not verify an installed part or its protection evidence, which tells the agent when this tool is the wrong evidence source. It stops short of naming the alternative tools (analyze_system, search_components) for those verification needs, so it is context without explicit routing.

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